Extraction-Free, Direct Determination of Caffeine in Microliter Volumes of Beverages by Thermal Desorption-Gas Chromatography Mass Spectrometry

<div>Typical chromatogram obtained for a 5 <i>μ</i>L sample of 117 <i>μ</i>g/mL caffeine (i) with lidocaine, internal standard (ii).</div>

International Journal of Analytical Chemistry

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Figure 2

Figure 2: Extraction-Free, Direct Determination of Caffeine in Microliter Volumes of Beverages by Thermal Desorption-Gas Chromatography Mass Spectrometry 

Figure 2 | Extraction-Free, Direct Determination of Caffeine in Microliter Volumes of Beverages by Thermal Desorption-Gas Chromatography Mass Spectrometry 