Calix[4]pyrrole-Grafted Gold Nanoparticles as a Turn-On Fluorescence Sensor for Noxious Fungicide Dimoxystrobin and Their Anti-Cancer Activity against the KB-3-1 Cell Line

A rapid and easy approach for producing very stable gold nanoparticles has been discovered. Calix[4]pyrrole tetrahydrazide (CPTAH) was utilized effectively in the synthesis of gold nanoparticles as a reducing and stabilizing agent. These functionalized AuNPs were characterized by Surface Plasmon Resonance, Transmission Electron Microscopy, Selected Area Electron Diffraction, and Energy Dispersive X-ray techniques. CPTAH-AuNPs possessed a particle size of 11 +/- 2 nm and are highly stable at pH 7.0 for more than 150 days. The selectivity and sensitivity of CPTAH-AuNPs as a fungicide sensor was assessed for Metalaxyl, Mancozeb, Tebuconazole, Tricyclozole, Dimoxystrobin, Kresoxim-methyl, and Carbendazim, amongst which Dimoxystrobin (DMX) was sensed exclusively with naked eyes by means of aggregation of CPTAH-AuNPs with a detection limit of the order of 5 ppm using "Turn-on" fluorescence enhancement. Additionally, the CPTAH-AuNPs were found to be effective cytotoxic agent against the human cervix cancer cell line KB-3-1 with IC50 value of 64.63 mu g/mL which admits the employability of CPTAH-AuNPs in the study of development of anti-cancer drug.