Evaluation of the H2S and NO adsorption and release capacity of PEG-zeolites and PEG-titanosilicates composites

The exogeneous delivery of hydrogen sulfide (H2S) and nitric oxide (NO) has proven to have several therapeutic effects. However, the development of porous materials to be used as drug carries, specifically as carriers of gaseous molecules, is still in its infancy. In here, we synthesized and characterized four polyethylene glycol (PEG) composites obtained from two different kinds of zeolites (4A and Y) and two titanosilicates (ETS-4 and ETS-10). The H2S and NO adsorption capacities are important aspects of the H2S/NO carriers, and they were determined for all the PEG-composites. Additionally, release studies of the H2S/NO loaded composites in aqueous solution at physiological pH revealed a longer NO release than their parent material while for H2S this was not observed, yet the % of released H2S is higher than the parent material. Cytotoxicity studies using HeLa cell line showed that PEG composites at 450 μg/mL have no toxicity. The results indicate that all PEG composites may have potential as NO-carrier, while for H2S only the 4A@PEG may be evaluated. [Display omitted] •Zeolites and titanosilicates were successfully functionalized by grafting PEG.•PEG functionalized samples released more amount of H2S.•PEG functionalized samples released NO for longer times.•Biocompatibility was improved.•The modification method can be extended to other porous NO carriers.