Determination of picomole amounts of formaldehyde in air and bio-fluids based on its enhanced myoglobin-luminol chemiluminescence reaction

Abstract

A rapid and sensitive chemiluminescence determination of formaldehyde with the flow injection technique was presented. It was found that the specific binding of myoglobin with formaldehyde could accelerate the electron transfer between myoglobin and luminol, thus producing quicker and more efficient chemiluminescence at 425 nm than with the myoglobin–luminol reaction. The increased chemiluminescence intensity was linear with the formaldehyde concentration in the range of 1–3000 pmol L−1, and the limit of detection was 0.3 pmol L−1 with a relative standard deviation of less than 5.0% (3σ). At a flow rate of 2.0 mL min−1, including sampling and washing, the assay could be accomplished in 0.5 min. It was also found that there was a linear relationship between the vapour pressure of formaldehyde and temperatures of 291.5–315.0 K. The proposed method has been applied successfully for the determination of formaldehyde in air and human serum.