Silver nanoparticles and Cu (II) as a colorimetric sensor for detection of cefazolin in food and biological samples

This research presents a method for detecting Cefazolin using silver nanoparticles (AgNPs) and Cu (II) ions. Cefazolin, a β-lactam antibiotic, exhibits a broad spectrum of applications in the field of medicine. The introduction of Cefazolin had a very slight color change within a solution of silver nanoparticles, thereby the little aggregation should be enhanced. The involvement of Cu(II) within the system proved essential for the detection of Cefazolin, leading to the aggregation of silver nanoparticles and a noticeable shift in color from yellow to pink. As a result, the surface plasmon resonance band around 400 nm decreases, and a new band appears at 515 nm. Under optimal conditions, the Cefazolin linear range was 10.0-200.0 ng mL^-1, with a detection limit of 1.6 ng mL^-1. The relative standard deviations (RSD) for ten replicate measurements of 20.0 and 200.0 ng mL^-1 of Cefazolin sodium were 4.7 and 2.9%, respectively, showing that the proposed system has acceptable reproducibility. The method was successfully applied to Cefazolin detect in various samples such as food, serum, and human urine.