Application of porous membrane-protected chitosan microspheres to determine benzene, toluene, ethylbenzene, xylenes and styrene in water

Chitosan (CS) microspheres were synthesized by the precipitation method and cross-linked with glutaraldehyde. The cross-linked CS microspheres (20 mg) were used as sorbents for the micro-solid phase extraction (μ-SPE) of benzene, toluene, ethylbenzene, xylenes and styrene (BTEX-S) from water. The μ-SPE device consisted of a sealed polypropylene envelope housing the microspheres for the evaluation of the extraction efficiency. Analysis was by gas chromatography-mass spectrometry (GC-MS). Under the optimized conditions, the method provided linearity range of between 0.5 and 50 μg L−1 with good correlation coefficients of between 0.985 and 0.998. The relative standard deviations of μ-SPE coupled with GC-MS were found to be between 2 and 3%. Method detection limits for BTEX-S were in the range of between 0.01 and 0.04 μg L−1 while the relative recoveries were in the range of between 59 and 97%. The proposed method is a cost effective, fast and environmentally friendly extraction technique with ease of operation and minimal usage of organic solvent.