Dual β-cyclodextrin functionalized Au@SiC nanohybrids for the electrochemical determination of tadalafil in the presence of acetonitrile.

This finding described the electrochemical detection of tadalafil based on CM-β-cyclodextrin and SH-β-cyclodextrin functionalized Au@SiC nanohybrids film. The tadalafil electrochemical signal could be dramatically amplified by introducing 40% of acetonitrile in buffer medium and further enhanced by the host-guest molecular recognition capacity of β-cyclodextrin. Uniform and monodispersed ~5.0 nm Au NPs were anchored on the SiC-NH2 surface via a chemical reduction process by using polyethylene glycol and sodium citrate as dispersant and stabilizing agent. CM-β-CD was covalently bound on Au@SiC by combining the amine group of SiC-NH2 with the carboxyl group of CM-β-CD with the aid of EDC/NHS coupling agent. SH-β-CD could tightly attach to the surface of Au@SiC by the strong coordinating capability between Au and thiol. Differential pulse voltammetry was successfully used to quantify tadalafil within the concentration range of 0.01-100 µM under optimal conditions with a detection limit (S/N = 3) of 2.5 nM. In addition, the β-CD-Au@SiC nanohybrid electrochemical sensor showed high selectivity to two other erectile dysfunction drugs sildenafil and vardenafil. The proposed electrochemical sensing platform was successfully used to determine tadalafil in raw materials, herbal sexual health products, and spiked human serum samples.