Molecularly imprinted peptide-based enzyme mimics with enhanced activity and specificity

Area of Science:

• Biomimetic chemistry
• Catalysis
• Nanomaterials

Background:

• Peroxidase enzymes play crucial roles in biological systems.
• Developing artificial enzyme mimics with high efficiency and specificity is a significant challenge.
• Peptide self-assembly and molecular imprinting offer strategies for catalyst design.

Purpose of the Study:

• To construct and characterize novel peroxidase-mimicking catalysts using peptide assembly and molecular imprinting.
• To enhance catalytic activity and substrate specificity through synergistic design strategies.
• To investigate the influence of molecular imprinting and electrostatic interactions on catalytic performance.

Main Methods:

• Co-assembly of Fmoc-FFH peptide and Hemin to form CA-H/Hemin.
• Fabrication of an ABTS-imprinted polymer combined with CA-H/Hemin to create MIP-H/Hemin.
• Introduction of cationic monomers to synthesize a positively charged imprinted catalyst, MIP+-H/Hemin.
• Evaluation of catalytic activity using 2,2'-azinobis-(3-ethylbenzthiazoline-6-sulphonate) (ABTS) and 3,3',5,5'-tetramethylbenzidine (TMB) as substrates.

Main Results:

• CA-H/Hemin exhibited a 21-fold rate acceleration for ABTS oxidation.
• MIP-H/Hemin demonstrated a 52-fold rate acceleration due to enhanced re-binding toward ABTS.
• MIP+-H/Hemin achieved a 137-fold rate enhancement via synergistic effects of molecular imprinting and electrostatic attraction.
• MIP-H/Hemin and MIP+-H/Hemin showed substrate specificity towards ABTS over TMB.

Conclusions:

• Peptide assembly and molecular imprinting are effective strategies for creating high-performance peroxidase mimics.
• Synergistic integration of molecular imprinting and electrostatic attraction significantly boosts catalytic activity and specificity.
• The developed catalysts offer a promising platform for advanced applications requiring enzyme mimicry.