A sensitive flow analysis system for the fluorimetric determination of low levels of formaldehyde in alcoholic beverages

摘要

A sensitive FIA method was developed for the selective determination of formaldehyde in alcoholic beverages.This method is based on the reaction of Fluoral-P(4-amine-3-pentene-2-one)with formaldehyde,leading to the formation of 3,5-diacetyl-1,4-dihydrolutidine(DDL),which fluoresces at lambda_(ex)= 410nm and lambda_(em)= 510nm.The analytical parameters were optimized by the response surface method using the Box-Behnken design.The proposed flow injection system allowed for the determination of up to 3.33 x 10~(-5)molL~(-1)of formaldehyde with R.S.D.< 2.5% and a detection limit of 3.1 ng mL~(-1).The method was successfully applied to determine formaldehyde in alcoholic beverages,without requiring any sample pretreatment,and the results agreed with the reference at a 95% confidence level by paired t-test.In the optimized condition,the FIA system proved able to analyze up to 60 samples/h.