Journal of Analytical Methods in Chemistry The latest articles from Hindawi Publishing Corporation © 2016 , Hindawi Publishing Corporation . All rights reserved. The Effect of Salt-Processed Psoralea corylifolia on Generative Organ Targeting Thu, 20 Oct 2016 14:01:46 +0000 Psoralen and isopsoralen are two isomers and main effective components within Psoralea corylifolia. In order to investigate the salt-processing effect on tissue distribution characters of psoralen and isopsoralen, a sensitive and accurate ultrahigh pressure liquid chromatographic tandem mass spectrometric (UHPLC-MS/MS) method has been developed and validated for simultaneous determination of the 2 components in rats’ tissues after administration of the extracts that came from either crude or salt-processed Psoralea corylifolia L. Data displayed that both areas under the curve (AUC) of psoralen and isopsoralen from salt-processed scurfpea fruit group were significantly increased compared with that of the crude herb group, especially in heart (), ovary, and testes (). Though the RE and of psoralen and isopsoralen in all of the investigated organs were over 1.0, generative organs kept the maximum value. The experiment manifested that salt-processing of scurfpea fruit can increase the distribution of psoralen and isopsoralen to generative organs, heart and spleen, and the distribution of psoralen and isopsoralen to generative organs is significantly higher compared to heart and spleen (). Results indicate that salt-processing of scurfpea fruit can significantly increase the distribution of psoralen and isopsoralen to generative organs. Gen-hua Zhao, Cui-ping Yan, Zi-sheng Xu, Qian-qian Gao, Zhi-peng Chen, and Wei-dong Li Copyright © 2016 Gen-hua Zhao et al. All rights reserved. Urinary Concentrations of Steroids in Bulls under Anabolic Treatment by Revalor-XS® Implant Thu, 20 Oct 2016 12:05:41 +0000 Despite the European ban of using anabolics in food-producing animals, growth promoters might still be illegally used in the European Union. To control the food chain and guarantee consumers’ health, there is a need of highly sensitive analytical methods for the identification of marker residues of such treatments. In the present study, a group of bulls () received trenbolone acetate (200 mg) and estradiol (40 mg) by a commercial ear implant during a time range of 71 days, and a second group () was kept for control. The aim of the research was to measure the residual urinary concentrations of the administered drugs (β-trenbolone and β-estradiol), their main metabolites (α-trenbolone and α-estradiol), and possible alterations of the urinary profile of other endogenous hormones metabolically related. The analytical method was based on liquid chromatography-tandem mass spectrometry. Results showed average urinary concentrations of α-trenbolone and α-estradiol during treatment in the range of () ng mL−1 and () ng mL−1, respectively, whereas β-trenbolone and β-estradiol exhibit urinary concentrations lower than 0.22 ng mL−1 in both cases. Data obtained from the urinary profiles of endogenous steroids indicate that they could be useful to indirectly detect the ongoing treatment. Giancarlo Biancotto, Roberto Stella, Federica Barrucci, Francesca Lega, and Roberto Angeletti Copyright © 2016 Giancarlo Biancotto et al. All rights reserved. The Influence of the Variety, Vineyard, and Vintage on the Romanian White Wines Quality Wed, 19 Oct 2016 14:09:02 +0000 The wine is one of the most consumed drinks over the world, being subjected to falsification or adulteration regarding the variety, vintage, and geographical region. In this study, the influence of different characteristics of wines (type, production year, and origin) on the total phenolic content, total flavonoids content, antioxidant activity, total sugars content, pH, and 18O/16O isotopic ratio was investigated. The differentiation of selected wines on the basis of tested parameters was investigated using chemometric techniques, such as analysis of variance, cluster analysis, and principal component analysis. The experimental results are in agreement with other outcomes and allow concluding that variety and vineyard have the major influence on the studied parameters, but, also, statistical interaction effect between year and vineyard and year and variety is observed in some cases. The obtained results have demonstrated that these parameters together with chemometric techniques show a significant potential to be used for discrimination of white wines. Anamaria Hosu, Veronica Floare-Avram, Dana Alina Magdas, Ioana Feher, Mihai Inceu, and Claudia Cimpoiu Copyright © 2016 Anamaria Hosu et al. All rights reserved. Assessment for Melting Temperature Measurement of Nucleic Acid by HRM Wed, 19 Oct 2016 06:44:30 +0000 High resolution melting (HRM), with a high sensitivity to distinguish the nucleic acid species with small variations, has been widely applied in the mutation scanning, methylation analysis, and genotyping. For the aim of extending HRM for the evaluation of thermal stability of nucleic acid secondary structures on sequence dependence, we investigated effects of the dye of EvaGreen, metal ions, and impurities (such as dNTPs) on melting temperature () measurement by HRM. The accuracy of HRM was assessed as compared with UV melting method, and little difference between the two methods was found when the DNA was higher than 40°C. Both insufficiency and excessiveness of EvaGreen were found to give rise to a little bit higher , showing that the proportion of dye should be considered for precise measurement of nucleic acids. Finally, HRM method was also successfully used to measure s of DNA triplex, hairpin, and RNA duplex. In conclusion, HRM can be applied in the evaluation of thermal stability of nucleic acid (DNA or RNA) or secondary structural elements (even when dNTPs are present). Jing Wang, Xiaoming Pan, and Xingguo Liang Copyright © 2016 Jing Wang et al. All rights reserved. Determination of Levetiracetam in Human Plasma by Dispersive Liquid-Liquid Microextraction Followed by Gas Chromatography-Mass Spectrometry Mon, 17 Oct 2016 11:16:45 +0000 Levetiracetam (LEV) is an antiepileptic drug that is clinically effective in generalized and partial epilepsy syndromes. The use of this drug has been increasing in clinical practice and intra- or -interindividual variability has been exhibited for special population. For this reason, bioanalytical methods are required for drug monitoring in biological matrices. So this work presents a dispersive liquid-liquid microextraction method followed by gas chromatography-mass spectrometry (DLLME-GC-MS) for LEV quantification in human plasma. However, due to the matrix complexity a previous purification step is required. Unlike other pretreatment techniques presented in the literature, for the first time, a procedure employing ultrafiltration tubes Amicon® (10 kDa porous size) without organic solvent consumption was developed. GC-MS analyses were carried out using a linear temperature program, capillary fused silica column, and helium as the carrier gas. DLLME optimized parameters were type and volume of extraction and dispersing solvents, salt addition, and vortex agitation time. Under chosen parameters (extraction solvent: chloroform, 130 μL; dispersing solvent: isopropyl alcohol, 400 μL; no salt addition and no vortex agitation time), the method was completely validated and all parameters were in agreement with the literature recommendations. LEV was quantified in patient’s plasma sample using less than 550 μL of organic solvent. Greyce Kelly Steinhorst Alcantara, Leandro Augusto Calixto, Luiz Alberto Beraldo de Moraes, Regina Helena Costa Queiroz, Anderson Rodrigo Moraes de Oliveira, and Cristiane Masetto de Gaitani Copyright © 2016 Greyce Kelly Steinhorst Alcantara et al. All rights reserved. Rapid and Quantitative Determination of S-Adenosyl-L-Methionine in the Fermentation Process by Surface-Enhanced Raman Scattering Thu, 13 Oct 2016 09:46:31 +0000 Concentrations of S-Adenosyl-L-Methionine (SAM) in aqueous solution and fermentation liquids were quantitatively determined by surface-enhanced Raman scattering (SERS) and verified by high-pressure liquid chromatography (HPLC). The Ag nanoparticle/silicon nanowire array substrate was fabricated and employed as an active SERS substrate to indirectly measure the SAM concentration. The linear relationship between the integrated intensity of peak centered at ~2920 cm−1 in SERS spectra and the SAM concentration was established, and the limit of detections of SAM concentrations was analyzed to be ~0.1 g/L. The concentration of SAM in real solution could be predicted by the linear relationship and verified by the HPLC detection method. The relative deviations (δ) of the predicted SAM concentration are less than 13% and the correlation coefficient is 0.9998. Rolling-Circle Filter was utilized to subtract fluorescence background and the optimal results were obtained when the radius of the analyzing circle is 650 cm−1. Hairui Ren, Zhaoyang Chen, Xin Zhang, Yongmei Zhao, Zheng Wang, Zhenglong Wu, and Haijun Xu Copyright © 2016 Hairui Ren et al. All rights reserved. Biotinylation of Deoxyguanosine at the Abasic Site in Double-Stranded Oligodeoxynucleotides Wed, 12 Oct 2016 12:18:51 +0000 Biotinylation of deoxyguanosine at an abasic site in double-stranded oligodeoxynucleotides was studied. The biotinylation of deoxyguanosine is achieved by copper-catalyzed click reaction after the conjugation of the oligodeoxynucleotide with 2-oxohex-5-ynal. The biotinylation enables visualization of the biotinylated oligodeoxynucleotides by chemiluminescence on a nylon membrane. In order to investigate the biotinylated site, the biotinylated oligodeoxynucleotides were amplified by the DNA polymerase chain reaction. Replacement of guanine opposing the abasic site with adenine generated by the activity of the terminal deoxynucleotidyl transferase of DNA polymerase was detected by DNA sequencing analysis and restriction endonuclease digestion. This study suggests that 2-oxohex-5-ynal may be useful for the detection of the unpaired deoxyguanosine endogenously generated at abasic sites in genomic DNA. Chun Wu Copyright © 2016 Chun Wu. All rights reserved. Sensing Estrogen with Electrochemical Impedance Spectroscopy Mon, 10 Oct 2016 13:52:38 +0000 This study demonstrates the application feasibility of electrochemical impedance spectroscopy (EIS) in measuring estrogen (17β-estradiol) in gas phase. The present biosensor gives a linear response () for 17β-estradiol vapor concentration from 3.7 ng/L to 3.7 × 10−4 ng/L with a limit of detection (3.7 × 10−4 ng/L). The results show that the fabricated biosensor demonstrates better detection limit of 17β-estradiol in gas phase than the previous report with GC-MS method. This estrogen biosensor has many potential applications for on-site detection of a variety of endocrine disrupting compounds (EDCs) in the gas phase. Jing Li, Byung Kun Kim, Kang-Kyun Wang, Ji-Eun Im, Han Nim Choi, Dong-Hwan Kim, Seong In Cho, Won-Yong Lee, and Yong-Rok Kim Copyright © 2016 Jing Li et al. All rights reserved. Evaluation of Trace Metal Profile in Cymbopogon validus and Hyparrhenia hirta Used as Traditional Herbs from Environmentally Diverse Region of Komga, South Africa Tue, 04 Oct 2016 11:11:02 +0000 FAAS was used for the analysis of trace metals in fresh and dry plant parts of Cymbopogon validus and Hyparrhenia hirta species with the aim of determining the trace metals concentrations in selected traditional plants consumed in Eastern Cape, South Africa. The trace metal concentration (mg/kg) in the samples of dry Cymbopogon validus leaves (DCVL) showed Cu of ; Zn of ; Fe of ; Mn of ; Pb of  mg/kg, while the samples of fresh Hyparrhenia hirta flowers (FHHF) gave Cu of ; Zn of ; Fe of ; Mn of ; Pb of  mg/kg. Abundance of metal concentrations follows the order: Cu > Fe > Pb > Mn > Zn in the flower samples of Cymbopogon validus and Hyparrhenia hirta species. The concentrations of trace metals in both plant parts were below the permissible limits (PL) set by WHO. It is suggested that pharmacovigilance be carried out periodically to improve the quality, safety, and efficiency of various herbal products. Babalwa Tembeni, Opeoluwa O. Oyedeji, Ikechukwu P. Ejidike, and Adebola O. Oyedeji Copyright © 2016 Babalwa Tembeni et al. All rights reserved. A Simple and Quick Method for the Determination of Pesticides in Environmental Water by HF-LPME-GC/MS Wed, 28 Sep 2016 16:01:19 +0000 This paper describes a simple and quick method for sampling and also for carrying out the preconcentration of pesticides in environmental water matrices using two-phased hollow fiber liquid phase microextraction (HF-LPME). Factors such as extraction mode, time, solvents, agitation, and salt addition were investigated in order to validate the LPME method. The following conditions were selected: 6 cm of polypropylene hollow fiber, ethyl octanoate as an acceptor phase, and extraction during 30 min under stirring at 200 rpm. The optimized method showed good linearity in the range of 0.14 to 200.00 μg L−1; the determination coefficient () was in the range of 0.9807–0.9990. The LOD ranged from 0.04 μg L−1 to 0.44 μg L−1, and LOQ ranged from 0.14 μg L−1 to 1.69 μg L−1. The recovery ranged from 85.17% to 114.73%. The method was applied to the analyses of pesticides in three environmental water samples (a spring and few streams) collected in a rural area from the state of Minas Gerais, Brazil. Helvécio C. Menezes, Breno P. Paulo, Maria José N. Paiva, and Zenilda L. Cardeal Copyright © 2016 Helvécio C. Menezes et al. All rights reserved. Total Arsenic, Cadmium, and Lead Determination in Brazilian Rice Samples Using ICP-MS Wed, 28 Sep 2016 15:29:35 +0000 This study is aimed at investigating a suitable method for rice sample preparation as well as validating and applying the method for monitoring the concentration of total arsenic, cadmium, and lead in rice by using Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Various rice sample preparation procedures were evaluated. The analytical method was validated by measuring several parameters including limit of detection (LOD), limit of quantification (LOQ), linearity, relative bias, and repeatability. Regarding the sample preparation, recoveries of spiked samples were within the acceptable range from 89.3 to 98.2% for muffle furnace, 94.2 to 103.3% for heating block, 81.0 to 115.0% for hot plate, and 92.8 to 108.2% for microwave. Validation parameters showed that the method fits for its purpose, being the total arsenic, cadmium, and lead within the Brazilian Legislation limits. The method was applied for analyzing 37 rice samples (including polished, brown, and parboiled), consumed by the Brazilian population. The total arsenic, cadmium, and lead contents were lower than the established legislative values, except for total arsenic in one brown rice sample. This study indicated the need to establish monitoring programs for emphasizing the study on this type of cereal, aiming at promoting the Public Health. Lidiane Raquel Verola Mataveli, Márcia Liane Buzzo, Luciana Juncioni de Arauz, Maria de Fátima Henriques Carvalho, Edna Emy Kumagai Arakaki, Richard Matsuzaki, and Paulo Tiglea Copyright © 2016 Lidiane Raquel Verola Mataveli et al. All rights reserved. Direct Analysis of Pharmaceutical Drugs Using Nano-DESI MS Wed, 28 Sep 2016 12:46:35 +0000 Counterfeit pharmaceutical drugs imply an increasing threat to the global public health. It is necessary to have systems to control the products that reach the market and to detect falsified medicines. In this work, molecules in several pharmaceutical tablets were directly analyzed using nanospray desorption electrospray ionization mass spectrometry (nano-DESI MS). Nano-DESI is an ambient surface sampling technique which enables sampling of molecules directly from the surface of the tablets without any sample pretreatment. Both the active pharmaceutical ingredients (APIs) and some excipients were detected in all analyzed tablets. Principal component analysis was used to analyze mass spectral features from different tablets showing strong clustering between tablets with different APIs. The obtained results suggest nano-DESI MS as future tool for forensic analysis to discern APIs present in unknown tablet samples. Carlos Cardoso-Palacios and Ingela Lanekoff Copyright © 2016 Carlos Cardoso-Palacios and Ingela Lanekoff. All rights reserved. Construction of a Turn Off-On-Off Fluorescent System Based on Competitive Coordination of Cu2+ between 6,7-Dihydroxycoumarin and Pyrophosphate Ion for Sensitive Assay of Pyrophosphatase Activity Tue, 27 Sep 2016 12:01:21 +0000 The detection of pyrophosphatase (PPase) activity is of great significance in diagnosing diseases and understanding the function of PPase-related biological events. This study constructed a turn off-on-off fluorescent system for PPase activity assay based on PPase-regulated competitive coordination of Cu2+ between a water-soluble fluorescent probe 6,7-dihydroxycoumarin (DHC) and pyrophosphate (PPi). The probe DHC can coordinate with Cu2+ and consequently display on-off type fluorescence response. Furthermore, the in situ formed nonfluorescent Cu2+-DHC complex can act as an effective off-on type fluorescent probe for sensing PPi due to the higher coordination reactivity between Cu2+ and PPi than that between Cu2+ and DHC. The subsequent addition of PPase to the mixture containing Cu2+, DHC, and PPi leads to the fluorescence requenching of the system again (an off state) because PPase catalyzes the hydrolysis of PPi into orthophosphate in the reaction system. Under the optimum conditions, the decrease of the fluorescence intensity of DHC-Cu2+-PPi system was linear with the increase of the PPase activity in the range from 0.1 to 0.3 U. The detection limit was down to 0.028 U PPase (). Moreover, the as-established system was also applied to evaluate PPase inhibitor. This study offers a simple yet effective method for the detection of PPase activity. Lingzhi Zhao, Liu Zhao, Yanqing Miao, Chunye Liu, and Chenxiao Zhang Copyright © 2016 Lingzhi Zhao et al. All rights reserved. Rapid Screening Method for Detecting Ethinyl Estradiol in Natural Water Employing Voltammetry Wed, 21 Sep 2016 13:28:23 +0000 17α-Ethinyl estradiol (EE2), which is used worldwide in the treatment of some cancers and as a contraceptive, is often found in aquatic systems and is considered a pharmaceutically active compound (PhACs) in the environment. Current methods for the determination of this compound, such as chromatography, are expensive and lengthy and require large amounts of toxic organic solvents. In this work, a voltammetric procedure is developed and validated as a screening tool for detecting EE2 in water samples without prior extraction, clean-up, or derivatization steps. Application of the method we elaborate here to EE2 analysis is unprecedented. EE2 detection was carried out using differential pulse adsorptive cathodic stripping voltammetry (DP AdCSV) with a hanging mercury drop electrode (HMDE) in pH 7.0 Britton-Robinson buffer. The electrochemical process of EE2 reduction was investigated by cyclic voltammetry at different scan rates. Electroreduction of the hormone on a mercury electrode exhibited a peak at − V versus Ag/AgCl. The experimental parameters were as follows: −0.7 V accumulation potential, 150 s accumulation time, and 60 mV s−1 scan rate. The limit of detection was 0.49 μg L−1 for a preconcentration time of 150 s. Relative standard deviations were less than 13%. The method was applied to the detection of EE2 in water samples with recoveries ranging from 93.7 to 102.5%. Chalder Nogueira Nunes, Lucas Ely Pauluk, Maria Lurdes Felsner, Vanessa Egéa dos Anjos, and Sueli Pércio Quináia Copyright © 2016 Chalder Nogueira Nunes et al. All rights reserved. Employing Solid Phase Microextraction as Extraction Tool for Pesticide Residues in Traditional Medicinal Plants Tue, 20 Sep 2016 16:39:23 +0000 HS-SPME was optimised using blank plant sample for analysis of organochlorine pesticides (OCPs) of varying polarities in selected medicinal plants obtained from northern part of Botswana, where OCPs such as DDT and endosulfan have been historically applied to control disease carrying vectors (mosquitos and tsetse fly). The optimised SPME parameters were used to isolate analytes from root samples of five medicinal plants obtained from Maun and Kasane, Botswana. The final analytes determination was done with a gas chromatograph equipped with GC-ECD and analyte was confirmed using electron ionisation mass spectrometer (GC-MS). Dieldrin was the only pesticide detected and confirmed with MS in the Terminalia sericea sample obtained from Kasane. The method was validated and the analyte recoveries ranged from to %, with RSDs ranging from 1.19 to 17.97%. The method indicated good linearity () in the range of 2 to 100 ng g−1. The method also proved to be sensitive with low limits of detection (LODs) ranging from to  ng g−1. It can be concluded that SPME was successfully utilized as a sampling and extraction tool for pesticides of diverse polarities in root samples of medicinal plants. Thamani T. Gondo, Veronica C. Obuseng, Lesego C. Mmualefe, and Harriet Okatch Copyright © 2016 Thamani T. Gondo et al. All rights reserved. Analyses of Total Alkaloid Extract of Corydalis yanhusuo by Comprehensive RP × RP Liquid Chromatography with pH Difference Mon, 19 Sep 2016 06:21:07 +0000 A comprehensive two-dimensional (2D) reverse phase (RP) liquid chromatography (LC) method is developed for alkaloid analysis. This offline comprehensive 2D method is developed using different pH values. With a pH value of 10.5, most alkaloids appear in the form of neutral molecules possessing high retention factors based on their polarity, while the alkaloid polarity order is changed when the pH value decreased to 3.0. The performance of pH modulated 2D LC is demonstrated with 8 alkaloid standards which resulted in orthogonal separation. The developed method is then applied to total alkaloid separation in Corydalis yanhusuo. The first-dimension separation is carried out using methanol and water containing 1.0% ammonium hydroxide and a strong base-resistant RP column, which afforded a peak capacity of 94. The second-dimension analysis is carried out with a surface positive charge column providing a peak capacity of 205 using a mobile phase consisting of acetonitrile and water with 0.15% formic acid. 2D analyses of total alkaloid extract from C. yanhusuo afford a total peak capacity of 9090. Sixteen compounds were tentatively identified based on their ultraviolet spectrum and MS/MS analyses. The proposed method provides an alternative approach to achieve high peak capacity for analysis of alkaloid extract. Xiaodong Wei, Hongling Shen, Lijun Wang, Qingyan Meng, and Wenjie Liu Copyright © 2016 Xiaodong Wei et al. All rights reserved. Polythiophene-Chitosan Magnetic Nanocomposite as a Highly Efficient Medium for Isolation of Fluoxetine from Aqueous and Biological Samples Thu, 08 Sep 2016 17:36:38 +0000 Polythiophene/chitosan magnetic nanocomposite as an adsorbent of magnetic solid phase extraction was proposed for the isolation of fluoxetine in aqueous and biological samples prior to fluorescence detection at 246 nm. The synthesized nanoparticles, chitosan and polythiophene magnetic nanocomposite, were characterized by scanning electron microscopy, FT-IR, TGA, and EDAX. The separation of the target analyte from the aqueous solution containing the fluoxetine and polythiophene/chitosan magnetic nanocomposite was simply achieved by applying external magnetic field. The main factors affecting the extraction efficiency including desorption conditions, extraction time, ionic strength, and sample solution pH were optimized. The optimum extraction conditions were obtained as 10 min for extraction time, 25 mg for sorbent amount, 50 mL for initial sample volume, methanol as desorption solvent, 1.5 mL for desorption solvent volume, 3 min for desorption time, and being without salt addition. Under the optimum conditions, good linearity was obtained within the range of 15–1000 μg L−1 for fluoxetine, with correlation coefficients 0.9994. Furthermore, the method was successfully applied to the determination of fluoxetine in urine and human blood plasma samples. Compared with other methods, the current method is characterized with highly easy, fast separation and low detection limits. Alireza Feizbakhsh, Amir Hossein Mohsen Sarrafi, and Shokooh Ehteshami Copyright © 2016 Alireza Feizbakhsh et al. All rights reserved. Capitalizing Resolving Power of Density Gradient Ultracentrifugation by Freezing and Precisely Slicing Centrifuged Solution: Enabling Identification of Complex Proteins from Mitochondria by Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry Wed, 07 Sep 2016 16:50:12 +0000 Density gradient centrifugation is widely utilized for various high purity sample preparations, and density gradient ultracentrifugation (DGU) is often used for more resolution-demanding purification of organelles and protein complexes. Accurately locating different isopycnic layers and precisely extracting solutions from these layers play a critical role in achieving high-resolution DGU separations. In this technique note, we develop a DGU procedure by freezing the solution rapidly (but gently) after centrifugation to fix the resolved layers and by slicing the frozen solution to fractionate the sample. Because the thickness of each slice can be controlled to be as thin as 10 micrometers, we retain virtually all the resolution produced by DGU. To demonstrate the effectiveness of this method, we fractionate complex V from HeLa mitochondria using a conventional technique and this freezing-slicing (F-S) method. The comparison indicates that our F-S method can reduce complex V layer thicknesses by ~40%. After fractionation, we analyze complex V proteins directly on a matrix assisted laser desorption/ionization, time-of-flight mass spectrometer. Twelve out of fifteen subunits of complex V are positively identified. Our method provides a practical protocol to identify proteins from complexes, which is useful to investigate biomolecular complexes and pathways in various conditions and cell types. Haiqing Yu, Joann J. Lu, Wei Rao, and Shaorong Liu Copyright © 2016 Haiqing Yu et al. All rights reserved. Ripening-Dependent Changes in Antioxidants, Color Attributes, and Antioxidant Activity of Seven Tomato (Solanum lycopersicum L.) Cultivars Wed, 07 Sep 2016 10:09:04 +0000 To evaluate the ripening-dependent changes in phytonutrients, seven commercial cultivars (two general and five cherry) of tomatoes were cultivated under greenhouse conditions. Fruits were harvested at breaker, turning, pink, light red, and red stages of each cultivar, and antioxidant contents, color attributes, and antioxidant activities were measured. During ripening process, lycopene content increased from the breaker to red stage, while lutein displayed the reverse accumulation pattern, with higher values during the breaker stage. In contrast, -carotene showed the highest levels of synthesis in pink and light red stages. Furthermore, flavonoids (quercetin, rutin, naringenin, and luteolin) also showed similar ripening-dependent changes, with higher quantities in pink and light red stages. Ascorbic acid showed continuously increasing patterns throughout ripening until the red stage, while the accumulation of total phenolics was cultivar-dependent. These results indicate that each antioxidant compound has a unique pattern of accumulation and degradation during the ripening process. “Unicon” exhibited highest total carotenoid (110.27 mg/100 g), total phenol (297.88 mg GAE/100 g) and total flavonoid content (273.33 mg/100 g), and consequently highest antioxidant activity (2552.4 μmol TE/100 g) compared to other cultivars. Throughout the ripening processes, total phenolics showed the highest correlation with antioxidant activity, followed by -carotene and total flavonoids. In conclusion, ripening in tomatoes is accompanied by incremental increases in various antioxidant compounds to some extent, as well as by concomitant increases in antioxidant activity. Shiva Ram Bhandari and Jun Gu Lee Copyright © 2016 Shiva Ram Bhandari and Jun Gu Lee. All rights reserved. Direct Comparison of 19F qNMR and 1H qNMR by Characterizing Atorvastatin Calcium Content Thu, 01 Sep 2016 06:45:47 +0000 Quantitative nuclear magnetic resonance (qNMR) is a powerful tool in measuring drug content because of its high speed, sensitivity, and precision. Most of the reports were based on proton qNMR (1H qNMR) and only a few fluorine qNMR (19F qNMR) were reported. No research has been conducted to directly compare the advantage and disadvantage between these two methods. In the present study, both 19F and 1H qNMR were performed to characterize the content of atorvastatin calcium with the same internal standard. Linearity, precision, and results from two methods were compared. Results showed that 19F qNMR has similar precision and sensitivity to 1H qNMR. Both methods generate similar results compared to mass balance method. Major advantage from 19F qNMR is that the analyte signal is with less or no interference from impurities. 19F qNMR is an excellent approach to quantify fluorine-containing analytes. Yang Liu, Zhaoxia Liu, Huaxin Yang, and Lan He Copyright © 2016 Yang Liu et al. All rights reserved. Determination of Very Low Level of Free Formaldehyde in Liquid Detergents and Cosmetic Products Using Photoluminescence Method Sun, 21 Aug 2016 14:42:22 +0000 Formaldehyde is commonly used in detergents and cosmetic products as antibacterial agent and preservative. This substance is unfavorable for human health because it is known to be toxic for humans and causes irritation of eyes and skins. The toxicology studies of this compound indicate risk of detergents and cosmetic formulations with a minimum content of 0.05% free formaldehyde. Therefore, determination of formaldehyde as quality control parameter is very important. In this study, a photoluminescence method was achieved by using 2-methyl acetoacetanilide. Also, the Box-Behnken design was applied for optimization of Hantzsch reaction for formaldehyde derivatization. The investigated factors (variables) were temperature, % v/v ethanol, reaction time, ammonium acetate, and 2-methyl acetoacetanilide concentration. The linear range was obtained from 0.33–20 × 10−7 M (1–60 μg·kg−1) and the limit of detection (LOD) was 0.12 μg·kg−1. The proposed method was applied for the analysis of Iranian brands of liquid detergents and cosmetic products. The formaldehyde content of these products was found to be in the range of 0.03–3.88%. Some brands of these products had higher concentration than the maximum allowed concentration of 0.2%. High recoveries (96.15%–104.82%) for the spiked dishwashing liquid and hair shampoo indicate the proposed method is proper for the assessment of formaldehyde in detergents and cosmetic products. The proposed methodology has some advantages compared with the previous methods such as being rapid, without the necessity of applying separation, low cost, and the fact that the derivatization reaction is carried out at room temperature without any heating system. Ali Gholami, Atefeh Mohsenikia, and Saeed Masoum Copyright © 2016 Ali Gholami et al. All rights reserved. A Study on the Reliability of an On-Site Oral Fluid Drug Test in a Recreational Context Wed, 17 Aug 2016 12:02:12 +0000 The reliability of DrugWipe 5A on site test for principal drugs of abuse (cannabis, amphetamines, cocaine, and opiates) detection in oral fluid was assessed by comparing the on-site results with headspace solid-phase microextraction (HS-SPME) gas chromatography-mass spectrometry (GC-MS) analysis on samples extracted by the device collection pad. Oral fluid samples were collected at recreational settings (e.g., discos, pubs, and music bars) of Rome metropolitan area. Eighty-three club goers underwent the on-site drug screening test with one device. Independently from the result obtained, a second device was used just to collect another oral fluid sample subsequently extracted and analyzed in the laboratory following HS-SPME procedure, gas chromatographic separation by a capillary column, and MS detection by electron impact ionization. DrugWipe 5A on-site test showed 54 samples (65.1%) positive to one or more drugs of abuse, whereas 75 samples (90.4%) tested positive for one or more substances following GC-MS assay. Comparing the obtained results, the device showed sensitivity, specificity, and accuracy around 80% for amphetamines class. Sensitivity (67 and 50%) was obtained for cocaine and opiates, while both sensitivity and accuracy were unsuccessful (29 and 53%, resp.) for cannabis, underlying the limitation of the device for this latter drug class. Stefano Gentili, Renata Solimini, Roberta Tittarelli, Giulio Mannocchi, and Francesco Paolo Busardò Copyright © 2016 Stefano Gentili et al. All rights reserved. Isolation and Analysis of Phospholipids in Dairy Foods Wed, 17 Aug 2016 09:50:32 +0000 The lipid fraction of milk is one of the most complex matrixes in foodstuffs due to the presence of a high number of moieties with different physical and chemical properties. Glycerolipids include glycerol and two fatty acids esterified in positions sn-1 and sn-2 with higher concentration of unsaturated fatty acids than in the triglyceride fraction of milk. Sphingolipids consist of a sphingoid base linked to a fatty acid across an amide bond. Their amphiphilic nature makes them suitable to be added into a variety of foods and recent investigations show that phospholipids, mainly phosphatidylserine and sphingomyelin, can exert antimicrobial, antiviral, and anticancer activities as well as positive effects in Alzheimer’s disease, stress, and memory decline. Polar lipids can be found as natural constituents in the membranes of all living organisms with soybean and eggs as the principal industrial sources, yet they have low contents in phosphatidylserine and sphingomyelin. Animal products are rich sources of these compounds but since there are legal restrictions to avoid transmission of prions, milk and dairy products are gaining interest as alternative sources. This review summarizes the analysis of polar lipids in dairy products including sample preparation (extraction and fractionation/isolation) and analysis by GC or HPLC and the latest research works using ELSD, CAD, and MS detectors. Lígia Pimentel, Ana Gomes, Manuela Pintado, and Luis Miguel Rodríguez-Alcalá Copyright © 2016 Lígia Pimentel et al. All rights reserved. Selective and Accurate Determination Method of Propofol in Human Plasma by Mixed-Mode Cation Exchange Cartridge and GC-MS Thu, 11 Aug 2016 14:12:17 +0000 A gas chromatography-mass spectrometry (GC-MS) method for the determination of propofol in human plasma has been developed and validated. Propofol was extracted from human plasma by using mixed-mode cation exchange/reversed-phase (MCX) cartridges. As propofol easily volatilizes during concentration, 100% methanol was injected directly into GC-MS to elute propofol. Despite avoiding concentration process of the eluted solution, lower limit of quantization (LLOQ) of propofol was 25 ng/mL. The validated method exhibited good linearity () with accuracy and precision −5.8%~11.7% and 3.7%~11.6%, respectively. The other validation parameters, recovery and matrix effect, ranged from 96.6% to 99.4% and 95.3% to 101.4%, respectively. Propofol standard was quantified to evaluate possible loss due to the concentration processes, nitrogen gas and centrifugal vacuum. These two concentration processes resulted in notable decrease in the quantity of propofol, signifying avoiding any concentration processes during propofol quantification. Also, to confirm suitability of the developed method, authentic human plasma samples were analyzed. The selective assay method using MCX cartridge and GC-MS facilitated quantification of propofol in plasma sample accurately by preventing any losses due to the concentration processes. Jae Sung Pyo Copyright © 2016 Jae Sung Pyo. All rights reserved. A Confirmatory Method Based on HPLC-MS/MS for the Detection and Quantification of Residue of Tetracyclines in Nonmedicated Feed Tue, 09 Aug 2016 15:33:23 +0000 The Commission Regulation 574/2011/EC set up maximum levels of coccidiostats and histomonostats in nonmedicated feed as a consequence of carry-over during manufacturing. Carry-over takes place from medicated to nonmedicated feed during feed production. Similar contamination could also occur for other pharmaceuticals such as tetracyclines, a group of antibiotics commonly employed in food production animal. The objective of this work is to present a simple and fast method for the simultaneous detection of four tetracyclines (chlortetracycline, doxycycline, oxytetracycline, and tetracycline) in nontarget feed at a μg/kg level. Validation of the method was performed according to the guideline included in the Commission Decision 2002/657/EC for official method. The validated method was successfully applied to 50 feed samples collected from different milk farms and 25 samples obtained from feed manufacturers. While oxytetracycline was the tetracycline most frequently detected, chlortetracycline was the analyte measured at the highest concentration 15.14 mg/Kg. From 75 nonmedicated feed analysed 15% resulted to be positive for the presence of one tetracycline. Rosa E. Gavilán, Carolina Nebot, Maria Veiga-Gómez, Paula Roca-Saavedra, Beatriz Vazquez Belda, Carlos M. Franco, and Alberto Cepeda Copyright © 2016 Rosa E. Gavilán et al. All rights reserved. Comparative Pharmacokinetics and Bioavailability of Epimedin C in Rat after Intramuscular Administration of Epimedin C, a Combination of Four Flavonoid Glycosides and Purified Herba Epimedii Extract Tue, 09 Aug 2016 07:21:37 +0000 Chuan-Ke-Zhi (CKZ), a purified Herba Epimedii extract, is a potent Chinese medicine preparation whose main bioactive components are a class of flavonoid glycosides such as epimedins A, B, and C and icariin. And epimedin C is far more abundant than other flavones in this extract. This study aims to investigate the pharmacokinetic and bioavailability of epimedin C and what effects, if any, other ingredients in CKZ have on its pharmacokinetics. Epimedin C, CKZ, and a combination of epimedins A, B, and C and icariin were, respectively, administrated to rats, and then the pharmacokinetic parameters of epimedin C in the three groups were calculated and compared. The result indicated that , , and of epimedin C were significantly different among the three groups (), and compared with the epimedin C group, the absorption of epimedin C significantly increased in the CKZ group. Furthermore, in this study the absolute bioavailability of epimedin C was also investigated by comparing intramuscular and intravenous administration of epimedin C. As a result, epimedin C could be quickly absorbed with extremely high absolute bioavailability after intramuscular administration. Shunjun Xu, Jiejing Yu, Liu Yang, Yaling Zhu, Shuai Sun, and Zhengdi Xu Copyright © 2016 Shunjun Xu et al. All rights reserved. Influence of Polyphosphoric Acid on the Consistency and Composition of Formulated Bitumen: Standard Characterization and NMR Insights Mon, 08 Aug 2016 09:45:21 +0000 Over the recent years, bitumen modification with polymers, acids, or mineral fillers has gained relevance to adjust its performance properties. This work reports the use of polyphosphoric acid (PPA) for the modification of formulated bitumen. With this objective, an in-depth literature review on PPA modification was firstly performed. Subsequently, five individual refinery components were selected for the preparation of bitumen blends, namely, asphaltic residue, vacuum residue, and three lube oils extracts. Seven binary/ternary bitumen blends were prepared and then treated with PPA. Afterwards, the five components and the unmodified and PPA-modified bitumen were characterized by standard methods (penetration, softening point, and penetration index), SARA analysis, elemental analysis, and 31P and 1H nuclear magnetic resonance (NMR) spectroscopy. The results evidenced higher asphaltenes and lower saturates/resins contents in PPA-modified bitumen. The NMR data suggest that the paraffinic chains became longer, the content of condensed aromatics increased, more substituted aromatic structures appeared, and -hydrogen in aromatic structures diminished. These findings disclosed the improved consistency and oxidation stability of PPA-modified bitumen blends. Catarina Varanda, Inês Portugal, Jorge Ribeiro, Artur M. S. Silva, and Carlos M. Silva Copyright © 2016 Catarina Varanda et al. All rights reserved. Model Analytical Development for Physical, Chemical, and Biological Characterization of Momordica charantia Vegetable Drug Sun, 07 Aug 2016 06:41:31 +0000 Momordica charantia is a species cultivated throughout the world and widely used in folk medicine, and its medicinal benefits are well documented, especially its pharmacological properties, including antimicrobial activities. Analytical methods have been used to aid in the characterization of compounds derived from plant drug extracts and their products. This paper developed a methodological model to evaluate the integrity of the vegetable drug M. charantia in different particle sizes, using different analytical methods. M. charantia was collected in the semiarid region of Paraíba, Brazil. The herbal medicine raw material derived from the leaves and fruits in different particle sizes was analyzed using thermoanalytical techniques as thermogravimetry (TG) and differential thermal analysis (DTA), pyrolysis coupled to gas chromatography/mass spectrometry (PYR-GC/MS), and nuclear magnetic resonance (1H NMR), in addition to the determination of antimicrobial activity. The different particle surface area among the samples was differentiated by the techniques. DTA and TG were used for assessing thermal and kinetic parameters and PYR-GC/MS was used for degradation products chromatographic identification through the pyrograms. The infusions obtained from the fruit and leaves of Momordica charantia presented antimicrobial activity. Deysiane Oliveira Brandão, Geovani Pereira Guimarães, Ravely Lucena Santos, Fernando José de Lima Ramos Júnior, Karla Monik Alves da Silva, Fabio Santos de Souza, and Rui Oliveira Macêdo Copyright © 2016 Deysiane Oliveira Brandão et al. All rights reserved. Extraction Efficiency of Different Solvents and LC-UV Determination of Biogenic Amines in Tea Leaves and Infusions Sun, 31 Jul 2016 16:53:13 +0000 Biogenic amines (BAs), that is, spermine, spermidine, putrescine, histamine, tyramine, β-phenylethylamine, cadaverine, and serotonin, have been determined in several samples of tea leaves, tea infusions, and tea drinks by LC-UV method after derivatization with dansyl chloride. Different extraction solvents have been tested and TCA 5% showed better analytical performances in terms of linearity, recovery percentages, LOD, LOQ, and repeatability than HCl 0.1 M and HClO4 0.1 M and was finally exploited for the quantitative determination of BAs in all samples. In tea leaves total BAs concentration ranged from 2.23 μg g−1 to 11.24 μg g−1 and PUT (1.05–2.25 μg g−1) and SPD (1.01–1.95 μg g−1) were always present, while SER (nd–1.56 μg g−1), HIS (nd–2.44 μg g−1), and SPM (nd–1.64 μg g−1) were detected more rarely. CAD and PHE were determined in few samples at much lower concentrations while none of the samples contained TYR. Tea infusions showed the same trend with total BAs concentrations never exceeding 80.7 μg L−1. Black teas showed higher amounts of BAs than green teas and organic and decaffeinated samples always contained much lower BAs levels than their conventional counterparts. U. Gianfranco Spizzirri, Nevio Picci, and Donatella Restuccia Copyright © 2016 U. Gianfranco Spizzirri et al. All rights reserved. Authentication of Coffea arabica according to Triacylglycerol Stereospecific Composition Thu, 28 Jul 2016 12:50:04 +0000 Stereospecific analysis is an important tool for the characterization of lipid fraction of food products. In the present research, an approach to characterize arabica and robusta varieties by structural analysis of the triacylglycerol (TAG) fraction is reported. The lipids were Soxhlet extracted from ground roasted coffee beans with petroleum ether, and the fatty acids (FA) were determined as their corresponding methyl esters. The results of a chemical-enzymatic-chromatographic method were elaborated by a chemometric procedure, Linear Discriminant Analysis (LDA). According to the total and intrapositional FA composition of TAG fraction, the obtained results were able to characterize roasted pure coffee samples and coffee mixtures with 10% robusta coffee added to arabica coffee. Totally correct classified samples were obtained when the TAG stereospecific results of the considered coffee mixture (90 : 10 arabica/robusta) were elaborated by LDA procedure. L. Cossignani, D. Montesano, M. S. Simonetti, and F. Blasi Copyright © 2016 L. Cossignani et al. All rights reserved.