Covalent synthesis, structural characterization and biological behavioral study of tin captured porphyrin-polyoxometalate based polymeric hybrid

The combination of polyoxometalates(POMs) and tin-based porphyrin in a variety of modes of interaction turned out to be the key for unlocking new directions in the study of biological activities. In this study, a new sandwich type covalently attached porphyrin C52H48N6O6Sn (SnTPP-Di-Tris) and Anderson POM-porphyrin polymeric hybrid, with molecular formula as [{N(C4H9)(4)}(8){C(6)2H(60)Mn(2)Mo(12)N(6)O(48)Sn center dot CH3CN}](PolySnP@POM). These compounds were clearly characterized and their formation was confirmed by spectroscopic (UV-visible, FT-IR, NMR) techniques, powder XRD, elemental analyses, cyclic voltammetry and scanning electron microscopy techniques(SEM). SnTPP-Di-Tris and PolySnP@POM were evaluated for drug delivery, DNA binding, protein binding and antibacterial studies. It is found that drug loading efficiency was 89% and 93% for PolySnP@POM and SnTPP-Di-Tris, respectively. While drug release was more efficient in acidic media (pH = 3) as 100 % for both compounds in 1.5 h as compared to basic media (pH = 11) 65.93% and 72.6% for SnTPP-Di-Tris and PolySnP@POM, respectively. Uv-visible study of SnTPP-Di-Tris and PolySnP@POM with salmon sperm DNA (SS-DNA) showed hypochromism trend which indicate intercalation mode of attachment and exhibited binding constant value 4.9 x 10(3) M-1 and 2.7 x 10(4) M-1 for SnTPP-Di-Tris and PolySnP@POM, respectively, referring that PolySnP@POM has more binding affinity than SnTPP-Di-Tris. Protein binding Study presented binding constant value (Kb) 3.09 x 10(4) M-1 and 1.30 x 10(4) M-1 for PolySnP@POM, and SnTPP-Di-Tris, correspondingly. Antibacterial activity results showed minor to significant activity. Furthermore, enhanced antibacterial activity of SnTPP-Di-Tris over its corresponding hybrid PolySnP@POM was observed because of lipophilic and more proliferating nature of SnTPP-Di-Tris.

Automated summary

The combination of polyoxometalates (POMs) and tin-based porphyrin has opened up new directions in the study of biological activities. A new sandwich type covalently attached porphyrin SnTPP-Di-Tris and Anderson POM-porphyrin polymeric hybrid PolySnP@POM were synthesized and characterized. These compounds were evaluated for drug delivery, DNA binding, protein binding, and antibacterial studies. PolySnP@POM showed higher drug loading efficiency, stronger DNA binding affinity, and better antibacterial activity compared to SnTPP-Di-Tris.