A novel nanocomposite of silver/titanium dioxide/chitosan adipate (Ag/TiO2/CS) was developed through
photochemical reduction using a chitosan adipate template. Chitosan served as a reducing agent
anchoring the metal ions through AgeN coordination bonds and electrostatic attractions, thus stabilizing
the Ag/TiO2/CS product observed by Fourier transform infrared spectroscopy and X-ray diffraction patterns.
Scanning electron microscopy observations revealed that the nanocomposite particles (50
e100 nm) were deposited onto the chitosan adipate layer. The product exhibited high z-potentials from
30.1 mV to 33.0 mV during 60 days of storage. In addition, the nanocomposite demonstrated higher
antimicrobial activity than AgNO3 or nano-Ag particles at similar concentrations, as evidenced by the
inhibition zone, minimum inhibitory concentrations (MIC), and growth curve. The nanocomposite
reduced the Escherichia coli population by 6 logs after 24 h of incubation, and had an MIC value of 0.38 mg
Ag/mL. These results suggest that Ag/TiO2/CS has the potential to be used as an antibacterial protective
coating for fruit storage.