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A method is described for the collection and quantitation of formaldehyde, acetaldehyde, and acetone in sidestream cigarette smoke. Using the "fishtail" chimney procedure (1), sidestream smoke is drawn by vacuum through the chimney, a Cambridge filter pad (Performance Systematics Inc.; Caledonia, MI), and into an impinger containing a solution of 2,4-dinitrophenylhydrazine (DNPH), whose solubility in acetonitrile was increased by using diglyme as a constituent of the collection derivatization solution. The chimney is rinsed with DNPH solution to remove "formaldehyde", and the rinse is added to the impinger solution. This combined wash and impinger solution is used to extract the Cambridge pad. An aliquot of the extract is analyzed by high-performance liquid chromatography using a reversed-phase column, ultraviolet detection, and a mobile phase gradient with tetrahydrofuran as a modifier. Acrolein is detected but gives poor precision and recovery because of dimer formation. For formaldehyde, acetaldehyde, and acetone, both the precision (7.30, 2.49, 2.88% relative standard deviation, respectively) and recovery (90.0, 95.2, 102.8%, respectively) are acceptable. The response for formaldehyde, acetaldehyde, and acetone is linear and a function of the number of cigarettes smoked. The minimum detectable quantity for the analytes ranges from 5 to 16 micrograms per cigarette.

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A reverse-phase liquid chromatography analysis is used to access the quantity of theobromine, (+)-catechin, caffeine, and (-)-epicatechin in Standard Reference Material 2384 Baking Chocolate, cocoa, cocoa beans, and cocoa butter using water or a portion of the mobile phase as the extract. The procedure requires minimal sample preparation. Theobromine, (+)-catechin, caffeine, and (-)-epicatechin are detected by UV absorption at 273 nm after separation using a 0.3% acetic acid-methanol gradient (volume fractions) and quantified using external standards. The limit of detection for theobromine, (+)-catechin, caffeine, and (-)-epicatechin averages 0.08, 0.06, 0.06, and 0.06 microg/mL, respectively. The method when applied to Standard Reference Material 2384 Baking Chocolate; baking chocolate reference material yields results that compare to two different, separate procedures. Theobromine ranges from 26000 mg/kg in cocoa to 140 mg/kg in cocoa butter; (+)-catechin from 1800 mg/kg in cocoa to below detection limits of < 32 mg/kg in cocoa butter; caffeine from 2400 mg/kg in cocoa to 400 mg/kg in cocoa butter, and (-)-epicatechin from 3200 mg/kg in cocoa to BDL, < 27 mg/kg, in cocoa butter. The mean recoveries from cocoa are 102.4 +/- 0.6% for theobromine, 100.0 +/- 0.6 for (+)-catechin, 96.2 +/- 2.1 for caffeine, and 106.2 +/- 1.7 for (-)-epicatechin.