Biomedical subjects

Wenlin Xie

Publications and source records attributed to Wenlin Xie.

2 recordsLinked to original sources

PubMed2006

Determination of cannabinoids in biological samples using a new solid phase micro-extraction membrane and liquid chromatography-mass spectrometry.

A simple, rapid and relatively solventless method for extraction of objective compounds would be useful for forensic, judicial and clinical purposes. Solid phase micro-extraction membrane (SPMEM) is one such extraction technique that integrates sampling, extraction and concentration into a single step, and combines the advantages of both the solid phase micro-extraction (SPME) and membrane separation. In this study, a new kind of membrane was prepared using polyamide and Tenax compounds, and applied to solid phase micro-extraction. Characteristics of the membrane such as adsorption capacity were tested. Extraction conditions such as adsorption time, desorption solvents, desorption time and assisted desorption treatment methods were studied and optimized. Tetrahydrocannabinol (THC) and cannabidiol (CBD) in blood and brain of the injected male mice, and in spiked human urine were extracted using this solid phase micro-extraction membrane method. The extracted THC and CBD were further determined with LC-MS using APCI. Ions analyzed in single ion monitoring mode were 315 for THC and CBD, and 318 for the deuterated THC internal standard.

Animals↗

PubMed2004

Preparation and usage of a new solid phase micro-extraction membrane.

Liquid-liquid or solid phase extraction methods are widely used for isolating analytes from urine, blood and other samples. But the preparation procedures of the samples are laborious, intensive, and costly. In addition, the organic solvents used are toxic to both the human body and the environment. An accurate, simple and rapid method for analysis of some compounds is required for forensic, judicial, and clinical purposes. Solid phase micro-extraction membrane (SPMEM) is a new, simple and solventless preparation technique. It integrates sampling, extraction and concentration into a single step and has the advantages of both the solid phase micro-extraction (SPME) and membrane separation. In this paper, a new kind of membrane used for the solid phase micro-extraction was prepared with amide compounds. The extraction conditions such as adsorption time, desorption solvents, methods and time are studied and optimized. The dichlorvos in the blood, morphine and phenobarbital in the urine were perfectly separated by using this solid phase micro-extraction membrane, and were tested by gas chromatograph-mass spectrometer (GC-MS). All the data were acquired in scan mode except that of morphine which was obtained in a selected ion monitoring (SIM) mode. Ions used for identification were those with m/z 57, 115, 162, 215, 285.

Adsorption↗