Nanomolar fluorescent quantitative detection of formaldehyde with a 8-hydroxyquinoline derivative in aqueous solution and electrospun nanofibers

A 8-hydroxyquinoline-based derivative was designed and synthesized, which is shown to act as a highly sensitive fluorescent probe for formaldehyde in aqueous solution. Based on the photo induced electron transfer (PET) process, addition of formaldehyde greatly enhanced the fluorescence of the probe. Formaldehyde can be detected quantitatively in the concentration range from 900   nM to 1.3   ×   10 −4   M and the detection limit on fluorescence response of the probe can be as low as 900   nM. The proposed method was successfully employed for preliminary application in several commercially available foods. Moreover, it has been successfully blended with a host polymer polyvinyl alcohol and the polymer containing the probe has been made in nanofiber form via electrospinning. The fluorescence of the nanofibers could also be enhanced after they were immersed into water solution of formaldehyde.