Preparation of molecular imprinted fluorescence sensor based on Er3+/ZnS QDs and its selective detection of ciprofloxacin in various matrices.

Background: Ciprofloxacin is a widely used antibiotic in medicine and agriculture. It can cause pollution to the environment and food, thereby affecting human health.

Objective: This study proposes the preparation of molecular imprinted fluorescent sensors and their selective detection of ciprofloxacin, with the aim of achieving specific recognition and accurate detection of ciprofloxacin.

Methods: Rare earth metal Er3+ is added to ZnS quantum dots to prepare a molecularly imprinted fluorescence sensor (MIP/Er3+/ZnS QDs). The effects of substance concentration, pH value, and time on the fluorescence detection intensity are analyzed to determine the optimal fluorescence detection conditions.

Results: Experimental results showed that the sensor accurately detected ciprofloxacin with a detection limit of 31 nmol/L and the linear range of 0.1-10 μmol/L. The sensor had a recovery rate of 99.7% to 103.5% for ciprofloxacin in milk samples, with a relative standard deviation of less than 5%, indicating accurate determination of ciprofloxacin content.

Conclusion: Molecularly imprinted fluorescent sensors have enormous application potential in the monitoring and control of ciprofloxacin, and are of great significance for ensuring environmental and food safety.