Determination of Formaldehyde in Human Tissue through Derivatization with 2 , 4 - Dinitrophenylhydrazine by Square Wave Polarography Method

The polarographic behaviour of formaldehyde (FA) was studied using cyclic and square wave polarography (SWP) methods. FA was derivatized with 2.4-dinitrophenylhydrazine (DNPH). The influence of several variables (including nature of the buffer, pH, concentration, scan rate, drop size, etc.) was examined in SWP method for FA. The best SWP responses were obtained in acetate buffer pH 5.0. The peak currents were measured with a static mercury drop electrode at -0.16 V versus Ag/AgCl. The linearity was established over the concentration range of 1-12 μg/mL for both methods in supporting electrolyte and human tissue. No electroactive interferences from the endogenous substances were found in the tissue samples. Mean recovery was 97.5%. The limits of detection and quantification of FA were 0.25 and 0.75 μg/mL, respectively. It was concluded that the developed method was accurate, sensitive, precise, reproducible and useful for the quality control of FA in solutions and spiked tissue.