Molecularly imprinted polymer hydrogel sheets with metalloporphyrin-incorporated molecular recognition sites for protein capture

• Published in: Talanta (Oxford) 2024-01, Vol.266 (Pt 2), p.125083, Article 125083
• Main Authors: Sullivan, Mark V., Nanalal, Sakshi, Dean, Bethanie E., Turner, Nicholas W.
• Format: Article
• Language: English
• Subjects: Hydrogel; MIP; Molecular recognition; Porphyrin; Protein recognition; Thin sheet
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2023.125083

Metalloporphyrins are often found in nature as coordination recognition sites within biological process, and synthetically offer the potential for use in therapeutic, catalytic and diagnostic applications. While porphyrin containing biological recognition elements have stability limitations, molecularly imprinted polymers bearing these structures offer an alternative with excellent robustness and the ability to work in extreme conditions. In this work, we synthesised a polymerizable porphyrin and metalloporphyrin and have incorporated these as co-monomers within a hydrogel thin-sheet MIP for the specific recognition of bovine haemoglobin (BHb). The hydrogels were evaluated using Scatchard analysis, with Kd values of 10.13 × 10−7, 5.30 × 10−7, and 3.40 × 10−7 M, for the control MIP, porphyrin incorporated MIP and the iron-porphyrin incorporated MIP, respectively. The MIPs also observed good selectivity towards the target protein with 73.8%, 77.4%, and 81.2% rebinding of the BHb target for the control MIP, porphyrin incorporated MIP and the iron-porphyrin incorporated MIP, respectively, compared with the non-imprinted (NIP) counterparts. Specificity was determined against a non-target protein, Bovine Serum Albumin (BSA). The results indicate that the introduction of the metalloporphyrin as a functional co-monomer is significantly beneficial to the recognition of a MIP, further enhancing MIP capabilities at targeting proteins. [Display omitted] •The design synthesis and incorporation of a polymerizable porphyrin and metalloporphyrin into a thin-sheet hydrogel MIP.•Use of metalloporphyrin as a co-monomer within the MIP thin sheet in order to improve binding.•Scatchard analysis showed Kd values of 10.13 × 10−7, 5.30 × 10−7, and 3.40 × 10−7 M, for the control MIP, porphyrin incorporated MIP and the iron-porphyrin incorporated MIP, respectively.•The MIP produced excellent selectivity for the target protein with 73.8%, 77.4%, and 81.2% rebinding of the BHb target for the control MIP, porphyrin incorporated MIP and the iron-porphyrin incorporated MIP, respectively.•This shows that the MIP has the potential to be a highly robust and selective material for molecular recognition use.