Abstract: | The analysis of organotin compounds based on the in situ simultaneous derivatization and extraction with sodium tetraethylborate has been optimized to overcome the most common matrix effect problems with biological samples. To obtain a complete dissolution of the samples, free of colloidal interfaces problems, mechanical agitation has been coupled with stirring in a warmed ultrasonic bath. A strict quality control system using three internal standards was implemented. Tripropyltin chloride was used as internal standard to assess the derivatization reaction and tetraoctyltin was used to check the overall extraction efficiency. Tetrabutyltin was used to verify the gas chromatography (with flame photometric detector) performance of the analyses. The technique was validated using Certified Reference Materials (NIES‐11 and BCR‐477) and has been applied successfully to different biological matrices (fish, mussels, oyster and barnacles). Copyright © 2002 John Wiley & Sons, Ltd. |