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Extraction and gas chromatographic determination of residual formaldehyde in micro-surgical materials.

A method for the extraction of residual formaldehyde from surgical materials after sterilisation and its gas chromatographic determination as the 2,4-dinitrophenylhydrazone derivative is described. Quantitative determinations are made using 9-cyanoanthracene as an internal standard, instead of anthracene, as reported previously, because this compound is more stable in solution. The sensitivity is of the order of 10 ng ml–1 of extracted aldehyde. To measure the released formaldehyde under the conditions closest to those of the human body, because of the purpose of these samples, the formaldehyde was also extracted with a physiological solution (0.9% NaCl), at 37 °C, with and without stirring.