N-Butyl-4-hydrazino-1,8-naphthalimide-Loaded Chitosan Self-Assembled Nanoparticles as Fluorescent Ratiometric Chemosensors for Detection of Formaldehyde

Formaldehyde (FA) is a typical volatile organic compound widely used in diverse fields, including decoration materials, textiles, and chemical processing. However, FA is also a carcinogen and poses a serious threat to human health. Therefore, the development of a rapid and efficient method for the detection of FA is a pressing concern. Herein, a kind of self-assembled fluorescent nanoparticle (CS-OCH3@NBHN) was designed and constructed by using a chitosan-based fluorescent probe (CS-OCH3) as a carrier, which was loaded with a small-molecule FA fluorescent probe. The nanoprobe CS-OCH3@NBHN proved to be rapid and highly sensitive for FA recognition, with a ratiometric fluorescence response of less than 10 min and a detection limit of 66.29 nM. In addition, the probe exhibited high selectivity to FA, good anti-interference ability, and a wide pH application range (pH 3.0–11.0). More importantly, it is applied for the sensitive detection of FA in aqueous solution, air, leather samples, and living cells.