Citrus aurantifulia extract as a capping agent to biosynthesis of gold nanoparticles: Characterization and evaluation of cytotoxicity, antioxidant, antidiabetic, anticholinergics, and anti-bladder cancer activity

In this study, new chemotherapeutic Au nanoparticles (AuNPs) were prepared to treat bladder cancer. AuNPs were synthesized using Citrus aurantifulia seed extract as the capping agent. Characterization of AuNPs was performed by Fourier-transform infrared (FT-IR), field emission scanning electron microscopy (FE-SEM), UV-Vis, energy-dispersive X-ray spectroscopy (EDS), and transmission electron microscopy (TEM). In UV-Vis, the exact peak in the wavelength of 522 nm revealed the formation of AuNPs. Besides, in the FE-SEM and TEM images, the AuNPs were spherical with range size of 17 to 24 nm. To investigate the antioxidant properties of AuNPs, the DPPH test was used. AuNPs inhibited half of the DPPH molecules in the concentration of 248 mu g/ml. MTT assay was used on bladder cancer (HT-1376, Grade 3, carcinoma), TCCSUP (Grade IV, transitional cell carcinoma), SCaBER (squamous cell carcinoma), and UM-UC-3 (transitional cell carcinoma) cell lines. AuNPs had very low cell viability and anti-bladder cancer properties dose dependently against HT-1376, TCCSUP, SCaBER, and UM-UC-3 cell lines. The best result of the anti-bladder cancer properties of AuNPs contrary to the above cell lines was observed in the case of SCaBER cell line. Additionally, these AuNPs were suitable inhibitors of the cholinesterase and alpha-glycosidase enzymes with K-i values of 55.32 + 5.32 and 148.78 +/- 23.83 mu M for alpha-glycosidase, 6.68 +/- 0.67 and 23.98 +/- 3.42 mu M for BChE, and 26.29 +/- 6.76 and 76.85 +/- 6.46 mu M for AChE, respectively. After confirming the recent results in the clinical trial studies, AuNPs may be used as antioxidant, antidiabetic, anticholinergics, and anti-bladder cancer supplements in human.