Pepsin mediated synthesis of blue fluorescent copper nanoclusters for sensing of flutamide and chloramphenicol drugs

Herein, we introduced a facile one-step green route for the synthesis of pepsin protected ultra-small blue fluorescent copper nanoclusters (pespsin-CuNCs) for the detection of flutamide and chloramphenicol drugs. The prepared pepsin capped CuNCs displayed excitation and emission peaks at 340 and 426 nm respectively with a quantum yield of 13.61%. The as-prepared pepsin-CuNCs exhibited specific fluorescence (FL) quenching by the addition of nitro group containing drugs (flutamide and chloramphenicol) as compared with other functional groups (–NH2, –OH and –SO2) containing drugs. The blue fluorescent pepsin-CuNCs showed linear FL quenching response with the addition of flutamide (0.10–100.00 µM) and chloramphenicol (5.00–100.00 µM) with detection limits of 61.82 and 188.32 nM, respectively. This proposed method provides a simple analytical protocol for the real time identification of flutamide and chloramphenicol in their pharmaceutical composition, biofluids and water samples.