A stir bar sorptive extraction device coupled with a gas chromatography flame ionization detector for the determination of abused prescription drugs in lean cocktail samples

A lean cocktail is a mixed drink for the non-medical use of prescription medications that has emerged in recent years as a drug of abuse and is related to drug-facilitated crimes. The determination of active ingredients in a lean cocktail is necessary for forensic investigations. This work presents an in-house developed stir bar sorptive extraction (SBSE) device with an XAD-2 adsorbent followed by analysis using GC-FID for the extraction and determination of the five main abused prescription drugs (diphenhydramine, tramadol, chlorpheniramine, dextromethorphan and promethazine) in lean cocktail samples. Under optimized conditions, the developed method provided linearity for 1.0-250 μg mL^-1 of each of the five abused prescription drugs. The limits of detection and limits of quantitation were in the respective ranges of 0.25-0.5 μg mL^-1 and 1.0-1.5 μg mL^-1. The percentage of extraction was 85.0-94.9%. The intra-day and inter-day precisions were 1.2-14.4% RSD and 1.4-15.8% RSD, respectively. Good relative recoveries in the range of 86.7-110.3% and 88.5-107.9% were obtained when the proposed method was applied for extraction and analysis of abused prescription drugs in five lean cocktail samples. The developed method can be a useful tool for measuring the levels of abused prescription drugs in a lean cocktail and the data could also be used as evidence in a forensic investigation.

Cooking has the potential to decrease the antitumor effect of fresh Betong watercress

Betong watercress (Nasturtium officinale R.Br.) contains phenethyl isothiocyanate (PEITC), derived from myrosinase-mediated hydrolysis of glucosinolates. Effects of fresh and cooked Betong watercress (FBW & CBW) on N-demethylation and C-8-hydroxylation of caffeine (CF) in rats were investigated. Wistar rats received a single dose of CF before and after pretreatments with a single or five-day administration of PEITC, FBW, and CBW dry powders. Plasma CF metabolic ratios (CMRs) were compared between before and after pretreatments. Single pretreatment with PEITC, FBW, but not CBW, significantly decreased CMRs. Five-day pretreatment with PEITC, FBW, and CBW significantly decreased CMRs. The decreases in CMRs after multiple doses of PEITC, FBW, and CBW were significantly higher than after a single dose. The decrease in CMRs caused by CBW was significantly lower than those by FBW, both single- and multiple doses. Cooking decreases the activity of FBW in inhibition of CYP1A2 mediating CF metabolism. PRACTICAL APPLICATIONS: PEITC and fresh watercress possess chemoprotective effects due to the inhibitory activity of PEITC on cytochrome P450s mediated bioactivation of carcinogens. Several clinical trials of the therapeutic uses of PEITC for cancer and other diseases are still in the pipeline. Betong watercress is a common ingredient in hot soup and stir-fried Thai recipes. Cooking heat inactivates plant myrosinase involving the production of PEITC. Consumption of watercress in cooked form may contribute less chemoprotective benefit. More appropriate preparation to deliver PEITC is needed to be evaluated.