Titanium aminophosphates: synthesis, characterization, antimicrobial and cytotoxicity studies

Abstract

Titanium aminophosphates were prepared using titanium tetraisopropoxide, phosphoric acid and aliphatic amines. The synthesized TNPAP, TNOAP and TNDDAP aminophosphates were characterized by various physicochemical techniques. Powder XRD spectra of titanium aminophosphates suggest the presence of a –Ti–O– phase. The % of titanium incorporated into the frameworks of titanium aminophosphates has been confirmed by EDAX analysis. The infrared and Raman spectra infer the presence of peaks due to vibrational bands of Ti–O, P–O, Ti–N, and P–N as well as Ti–O–P, and Ti–N–P linkages. The UV-Vis diffuse reflectance spectra reveal the presence of tetrahedral coordination of Ti in the framework. The XPS spectra suggest the presence of a –O–Ti–N– or –Ti–N–O– framework in TNPAP. The ³¹P MASNMR spectra of titanium aminophosphates indicate the presence of two environmentally different tetrahedrally co-ordinated phosphorous atoms in the TNPAP framework, while other titanium aminophosphates have unique phosphorous atoms in the framework. The TNPAP, TNOAP and TNDDAP were evaluated for biological applications. TNDDAP only exhibits antimicrobial and nematicidal activity against M. incognita at higher concentrations and incubation time. TNPAP and TNDDAP show λDNA cleavage activity while TNOAP does not. The in vitro anticancer activity has been studied using human cancer cell lines. TNPAP and TNOAP show anticancer activity only on the HL60 cell line. TNDDAP shows higher anticancer activity on HeLa and MCF7 cell lines and moderately on the HL60 cell line.