A simplified liquid chromatography-mass spectrometry assay for artesunate and dihydroartemisinin, its metabolite, in human plasma.

Artesunate (AS) is a potent antimalarial that is used worldwide for the treatment of malaria. A simple method with a total run time of 12 min was developed and validated for the quantification of AS and dihydroartemisinin (DHA), its active metabolite, in human (heparinized) plasma based on one-step protein precipitation in acetonitrile using artemisinin (ARN) as an internal standard, followed by liquid chromatography with a single quadrupole mass spectrometry system connected to a C18 column. Peak area ratio responses were fitted to the 2nd-order curve type, polynomial equation with weighting (1/concentration) over a quantification range between 3.

A sensitive HPLC-ESI-MS-MS method for the determination of cotinine in urine.

A simple, sensitive, selective, and reproducible method based on high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry was developed for the determination of nicotine and its major metabolite cotinine in human urine. The internal standard (acetaminophen) was separated from cotinine on a Hypersil Gold C(18) column with retention times of 9.3 and 13.

The influence of CYP2A6 polymorphisms and cadmium on nicotine metabolism in Thai population.

We investigated the influence of genetic, cadmium exposure and smoking status, on cytochrome P450-mediated nicotine metabolism (CYP2A6) in 182 Thai subjects after receiving 2mg of nicotine gum chewing for 30min. The urinary excretion of cotinine was normally distributed over a 2h period (logarithmically transformed). Individuals with urinary cotinine levels in the ranges of 0.

The influence of iron stores on cadmium body burden in a Thai population.

Cadmium is a toxin of increasing public health concern due to its presence in most human foodstuffs and in cigarette smoke. Exposure to cadmium leads to tissue bioaccumulation and, in particular, has nephrotoxic effects. The aim of the present study was to investigate the association between cadmium body burden and iron stores in a Thai population.

Cadmium exposure in Thai populations from central, northern and northeastern Thailand and the effects of food consumption on cadmium levels.

The aim of the present study was to investigate the association between cadmium body burden and the areas of exposure in Thailand, as well as blood pressure levels, the types and frequencies of foods, and alcohol consumption. A total of 182 healthy adult Thai subjects of both genders (89 males, 93 females) ages 18 to 57 years old weighing 40-95 kg were included in this study. Participants were residents from three main areas of Thailand: Pathum Thani Province (central Thailand; n=50), Khon Kaen Province (northeastern Thailand; n=43) and Mae Sot District, Tak Province (northern Thailand; n=89).