Preparation and spectral studies of boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B) as a new type of biological agents

Abstract

We have designed two novel magnetite targeting biological agents (Fe3O4@APTES-B(1,2)) with a core of Fe3O4 and a shell made of boronate esters (APTES-B) to improve the biological effectiveness of magnetite Fe3O4 nanoparticles (MNPs). Initially, two boronate esters (B1) and (B2) have been prepared by 3,4-dihydroxybenzaldehyde and phenylboronic acid and/or butylboronic acid using a Dean-Stark apparatus to remove the water formed during the esterification reactions. Then, the APTES-B1,2 compounds have been synthesized via boronate esters and APTES in the presence of 1–2 drops of formic acid as catalyst. Finally, magnetite Fe3O4 NPs were added to APTES-B1,2 compounds to afford boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B1,2) at ambient temperature, respectively. The boronate esters (B1) and (B2), APTES-B1,2 compounds, and boronate ester modified magnetite iron nanoparticles (Fe3O4@APTES-B1,2) were characterized using a combination of NMR (1H, 13C, and 11B), FT-IR, UV–Vis, LC-MS/MS, elemental analysis (CHN), XRD, SEM-EDX, EDX mapping, BET, and TG-DTA). Then, the antioxidant, antimicrobial and DNA binding activities of newly synthesized target compounds were tested. These results suggest that all compounds are also one of the propitious drug candidates and are worthy of further investigation.