Analysis of biological samples using solid-phase microextraction

Abstract

Solid-phase microextraction (SPME) has gained widespread acceptance for analyte-matrix separation and preconcentration. SPME is a simple, effective adsorption/ desorption technique that eliminates the need for solvents or complicated apparatus for concentrating volatile or nonvolatile compounds in liquid samples or headspace. SPME is compatible with analyte separation/detection by gas chromatography and high performance liquid chromatography and provides linear results for a wide range of concentrations of analytes. By controlling the polarity and thickness of the coating on the fiber, maintaining consistent sampling time, and adjusting several other extraction parameters, an analyst can ensure highly reliable results for low concentrations of analytes. This review provides updated information on SPME with chromatographic separation for the extraction and measurement of different analytes in biological fluids and materials. Firstly the background to the technique is given in terms of apparatus, fibers used, extraction conditions and derivatisation procedures. Then the different matrices, urine, blood, breast milk, hair and saliva are considered separately. Finally, the future potential of SPME for the analysis of biological samples in terms of the development of new devices and fiber chemistries as well as applications for in vivo studies are discussed.

Understanding Solid-Phase Microextraction: Key Factors Influencing the Extraction Process and Trends in Improving the Technique

“…Usually, polar and/or thermally unstable analytes are derivatized to improve their properties under the conditions of chromatographic separation. Derivatization usually involves the esterification of strongly acidic compounds such as acetic acid , and the conversion of amines and amphetamines to less polar and more volatile derivatives, , aldehydes and ketones to more stable oximes, , and phenols to acetates; organometallic compounds are converted to more volatile or more thermally stable derivatives. , The applications of chemically modified extraction fiber coatings are described in numerous review papers; they usually refer to the analysis of water, food, blood, and urine samples. − …”

An investigation of volatile organic compounds from the saliva of healthy individuals using headspace-trap/GC-MS

“…Nagler et al (2002) found a correlation between compounds in blood and saliva. Saliva has a lower concentration of constituents than blood due to the diurnal/circadian variations of certain compounds (Kumar et al 2009, Lima et al 2010. Lipophilic and neutral molecules diffused more easily into saliva than lipophobic, hydrophilic and ionized molecules (Lochner et al 1986).…”

Electrosynthesis of polypyrrole on steel fiber for solid-phase microextraction of citalopram in serum

“…SPME is a miniaturized and solvent-free sample preparation technique for chromatographic-spectrometric analysis by which the analytes are extracted from a gaseous or liquid sample by absorption in, or adsorption on, a thin polymer coating fixed to the solid surface of a fiber, inside an injection needle or inside a capillary [14]. SPME is applied to the analysis of blood, urine, oral fluid, and hair in clinical and forensic toxicology [15,16]. SPME has been successfully applied to the extraction of volatile and semivolatile drugs from biological samples mainly by coupling with GC [17,18].…”