Received: 28 September 2021 Accepted: 25 December 2021
Abstract:
A new A2B2-type porphyrin, namely: 5,15-bis-(3-hydroxyphenyl)-10,20-bis(3-methoxyphenyl)-porphyrin (trans-A2B2-porphyrin), and its platinum(II) derivative (Pt-trans-A2B2-porphyrin) were synthesized and completely characterized by UV–vis, FT-IR, 1H-NMR, 13C-NMR and AFM methods. The Pt-metalloporphyrin was complexed with colloidal gold (AuNPs) and the obtained nanomaterial (Pt-trans-A2B2-AuNPs) was able to optically detect the potassium salt of 1-anthraquinonsulfonic acid (AQ) in the concentration range 2.419 × 10–8 M to 2.5 × 10–7 M with relevance in medical investigations of microbial, congestive and cancer diseases, in diabetes and pancreatic fibrosis. The tested interfering species, selected from those usually present in physiological media, did not strongly influence the detection capacity of the complex nanomaterial toward AQ, even if the used concentrations are 50 times higher than that of the detected AQ. The AFM images of Pt-trans-A2B2-porphyrin, Pt-trans-A2B2-AuNPs and the hybrid material after 1-anthraquinonsulfonic acid detection (Pt-trans-A2B2-AuNPs-AQ) show significant morphologic differences from an uneven coverage with conical aggregates and holes having various sizes in the case of Pt-trans-A2B2-porphyrin, to columnar aggregates in the case of Pt-trans-A2B2-AuNPs hybrid material and finally to a relatively uniform distribution of self-assemblies for Pt-trans-A2B2-AuNPs after interacting with AQ, having lower dimensions than those of the used hybrid material. The detection mechanism was proposed and justified.