fluorescent sensing of pb2+ by microwave-assisted synthesized n-doped carbon dots: application of response surface methodology and doehlert design

In this work, a cheap, simple, selective and sensitive turnoff fluorescent sensor was presented for pb2+ determination. n-doped carbon dots (n-cds) were synthesized by microwave-assisted method. characterization of n-cds was performed by transmission electron microscopy, dynamic light scattering and fourier transform infrared spectroscopy. the important parameter (ph, concentration of carbon dots: ccds and time) was optimized with doehlert experimental design and response surface methodology. optimum condition for maximum turnoff was ph 3, ccds 8 mg ml−1 and 5 min. limit of detection and linear range was 0.02 µm and 0.05–25 µm.