Beta-galactooligosaccharides (GOS) are oligosaccharides normally produced industrially by transgalactosylation of lactose. They are also present naturally in the milk of many animals including humans and cows. GOS are thought to be good for health, being potential prebiotic fibres, and are increasingly added to food products. In order to control the GOS content of products, the AOAC official method 2001.02 was developed. However, the method has some shortcomings and in particular is unsuited to the analysis of products containing high levels of lactose such as infant formula. To overcome this problem, we developed a new method for application to infant formula and tested it on various GOS ingredients as well as infant formulae. When applied to GOS ingredients the results of the new method compare well with those of the official AOAC method, typically giving results in the range 90&#x2013;110&#x25; of those of the official method and having an expanded measurement uncertainty of less than 15&#x25;. For three products, the results were outside this range (recoveries of 80&#x2013;120&#x25; and expended measurement uncertainties up to 20&#x25;). When applied to the analysis of infant formula, recoveries were in the range of 92&#x2013;102&#x25; and the expanded measurement uncertainties were between 4.2 and 11&#x25;.

Sean Austin

Thierry B&#xe9;net

Julien Michaud

Denis Cuany

Philippe Rohfritsch

Determination of <i>&#x3b2;</i>-Galactooligosaccharides by Liquid Chromatography

The isomerization of lisinopril has been investigated using chromatographic, NMR spectroscopic, and theoretical calculations. The NMR data, particularly the NOEDIFF experiments, show that the major species that was eluted first is the <i>trans</i> form. The proportion was 77&#x25; and 23&#x25; for the <i>trans</i> and <i>cis</i>, respectively. The thermodynamic parameters (<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.04981041pt" id="M1" height="8.85534pt" version="1.1" viewBox="-0.0498162 -8.80553 19.6858 8.85534" width="19.6858pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g50-133" d="M610 0V27L347 666L316 657L46 26V0H610ZM504 54H116L310 537L504 54Z"/></g><g transform="matrix(.013,0,0,-0.013,8.496,0)"><path id="g50-73" d="M870 650H600L593 618C681 609 684 605 669 516L641 367H261L286 516C302 603 313 610 391 618L398 650H132L123 618C214 610 218 606 200 516L127 130C113 46 107 40 25 32L18 0H290L298 32C204 40 200 42 214 130L250 321H631L596 131C580 47 573 39 484 32L475 0H753L762 32C673 39 668 46 685 130L757 516C772 606 778 610 861 618L870 650Z"/></g></svg>, <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063904pt" id="M2" height="9.01192pt" version="1.1" viewBox="-0.0498162 -8.80553 14.8708 9.01192" width="14.8708pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g50-133"/></g><g transform="matrix(.013,0,0,-0.013,8.496,0)"><path id="g50-84" d="M463 633C453 636 427 644 417 648C388 660 349 667 316 667C183 667 100 592 100 483C100 398 176 335 223 305L259 282C321 242 358 203 358 149C358 66 301 22 234 22C110 22 70 131 57 208L24 205L28 48C51 23 128 -17 215 -17C342 -17 446 60 446 174C446 262 394 310 317 361L284 383C229 420 183 455 183 515C183 569 222 628 298 628C384 628 418 563 428 481L461 487C459 527 458 593 463 633Z"/></g></svg>, and <svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2063904pt" id="M3" height="9.01192pt" version="1.1" viewBox="-0.0498162 -8.80553 17.6763 9.01192" width="17.6763pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><use xlink:href="#g50-133"/></g><g transform="matrix(.013,0,0,-0.013,8.496,0)"><path id="g50-72" d="M722 297H451L442 267C561 257 561 253 547 182L531 98C521 44 465 24 390 24C228 24 130 134 130 296C130 482 252 628 465 628C592 628 657 579 656 458L692 461C695 540 699 605 702 631C664 642 590 667 492 667C203 667 24 502 24 285C24 93 170 -17 368 -17C464 -17 543 11 617 28C613 43 612 68 620 106L635 182C649 255 652 258 716 268L722 297Z"/></g></svg>) were determined by varying the temperature in the NMR experiments. The interpretations of the experimental data were further supported by DFT/B3LYP calculations.

Sondes Bouabdallah

Med Thaieb Ben Dhia

Med Rida Driss

Study of a Conformational Equilibrium of Lisinopril by HPLC, NMR, and DFT

Four simple, rapid, and accurate spectrophotometric methods were developed for the simultaneous determination of two food colorants, Carmoisine (E122) and Ponceau 4R (E124), in their binary mixtures and soft drinks. The first method is based on recording the first derivative curves and determining each component using the zero-crossing technique. The second method uses the first derivative of ratio spectra. The ratio spectra are obtained by dividing the absorption spectra of the binary mixture by that of one of the components. The third method, derivative differential procedure, is based on the measurement of difference absorptivities derivatized in first order of solution of drink samples in 0,1&#x2009;N NaOH relative to that of an equimolar solution in 0,1&#x2009;N HCl at wavelengths of 366 and 451&#x2009;nm for Carmoisine and Ponceau 4R, respectively. The last method, based on the compensation method is presented for derivative spectrophotometric determination of E122 and E124 mixtures with overlapping spectra. By using ratios of the derivative maxima, the exact compensation of either component in the mixture can be achieved, followed by its determination. These proposed methods have been successfully applied to the binary mixtures and soft drinks and the results were statistically compared with the reference HPLC method (NMKL 130).

Fatma Turak

Mithat Din&#xe7;

&#xd6;znur D&#xfc;lger

Mahmure Ustun &#xd6;zg&#xfc;r

Four Derivative Spectrophotometric Methods for the Simultaneous Determination of Carmoisine and Ponceau 4R in Drinks and Comparison with High Performance Liquid Chromatography

A simple, sensitive, accurate, and green spectrophotometric method for the determination of Cu(II) using newly synthesized reagent, 6-(2-methoxynaphthyl)-2,3-dihydro-1,2,4-triazine-3-thione (MNDTT), has been developed. MNDTT was synthesized based on the acylation of methoxy naphthalene and reaction of the product with amyl nitrite, which upon reaction with thiosemicarbazide yielded 6-(2-meyhoxynaphthyl)-2,3-dihydro-1,2,4-triazine-3-thione. MNDTT produces a dark red complex with copper in methanol according to the 1&#x2009;:&#x2009;2 stoichiometry. Beer&#x2019;s law was obeyed over the concentration range of 2.5&#x2013;20&#x2009;<i  >&#xb5;</i>g/mL with <svg     style="vertical-align:-0.20474pt;width:69.5625px;" id="M1" height="16.1" version="1.1" viewBox="0 0 69.5625 16.1" width="69.5625"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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</svg>. The limit of detection and limit of quantification were 0.33 and 1.10&#x2009;<i  >&#xb5;</i>g/mL, respectively. Within-day and between-day precision values were less than 3.68&#x25;. Finally, the method has been applied to a dental alloy (110-plus) successfully and the results were compared with atomic absorption method. The results showed that there was no significant difference between the two methods (<svg     style="vertical-align:-0.1638pt;width:58.712502px;" id="M2" height="11.375" version="1.1" viewBox="0 0 58.712502 11.375" width="58.712502"  xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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</svg>).

Maliheh Barazandeh Tehrani

Hutan Ghanbari

Effat Souri

Fazel Shamsa

Mohsen Amini

Synthesis of 6-(2-Methoxynaphthyl)-2,3-dihydro-1,2,4-triazine-3-thione as a New Reagent for Spectrophotometric Determination of Copper

The pressing issue of earthy and musty odor compounds in natural waters, which can affect the organoleptic properties of drinking water, makes it a public health concern. A simple and sensitive method for simultaneous analysis of five odorants in environmental water was developed by headspace solid-phase microextraction (HS-SPME) coupled to chromatography-mass spectrometry (GC-MS), including <i>geosmin</i> (GSM) and 2-methylisoborneol (2-MIB), as well as dimethyl trisulfide (DMTS), <i>&#x3b2;</i>-cyclocitral, and <i>&#x3b2;</i>-ionone. Based on the simple modification of original magnetic stirrer purchased from CORNING (USA), the five target compounds can be separated within 23&#x2009;min, and the calibration curves show good linearity with a correlation coefficient above 0.999 (levels&#x2009;=&#x2009;5). The limits of detection (LOD) are all below 1.3&#x2009;ng&#x2009;L<sup>&#x2212;1</sup>, and the relative standard deviation (&#x25;RSD) is between 4.4&#x25; and 9.9&#x25; (<svg xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg" style="vertical-align:-0.2129202pt" id="M1" height="8.45736pt" version="1.1" viewBox="-0.0498162 -8.24444 29.046 8.45736" width="29.046pt"><g transform="matrix(.013,0,0,-0.013,0,0)"><path id="g58-108" d="M532 0V30C473 38 467 38 467 107V298C467 395 416 451 336 451C307 451 279 439 251 420C226 404 205 389 185 374V453C142 434 94 422 43 413V386C98 378 104 373 104 309V107C104 41 100 38 31 30V0H251V30C191 35 185 40 185 107V337C216 364 255 389 295 389C360 389 386 347 386 276V110C386 44 380 35 321 30V0H532Z"/></g><g transform="matrix(.013,0,0,-0.013,10.916,0)"><path id="g54-34" d="M556 331V384H55V331H556ZM556 140V193H55V140H556Z"/></g><g transform="matrix(.013,0,0,-0.013,22.535,0)"><path id="g58-53" d="M453 623H65C60 580 57 531 46 472H80C104 539 109 548 175 548H389C309 380 194 169 90 0L98 -12L175 -2C274 207 366 407 462 610L453 623Z"/></g></svg>) and recoveries of the analytes from water samples are between 86.2&#x25; and 112.3&#x25;. In addition, the storage time experiment indicated that the concentrations did not change significantly for GSM and 2-MIB if they were stored in canonical environment. In conclusion, the method in this study could be applied for monitoring these five odorants in natural waters.

Zhen Ding

Shifu Peng

Weiwen Xia

Hao Zheng

Xiaodong Chen

Lihong Yin

Analysis of Five Earthy-Musty Odorants in Environmental Water by HS-SPME/GC-MS

About this journal

<p><em>International Journal of Analytical Chemistry</em> publishes research reporting new experimental results and chemical methods, especially in relation to important analytes, difficult matrices, and topical samples.</p>


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<p>Chief Editor, Professor Charles L. Wilkins, is a Distinguished Professor of Chemistry and Biochemistry at the University of Arkansas, USA. His research focuses on the development of novel analytical chemistry instrumentation and analysis paradigms.</p>


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International Journal of Analytical Chemistry | Hindawi

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International Journal of Analytical Chemistry publishes research reporting new experimental results and chemical methods, especially in relation to important analytes, difficult matrices, and topical samples.

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International Journal of Analytical Chemistry

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International Journal of Analytical Chemistry