中国生物工程杂志

Objective: Inspired by the principle of bionics, both anionic and cationic peptides with adhesive properties are designed and analyzed the effect of their mixing on adhesion to lay the foundation for the development of new bionic adhesive materials. Methods: The structural characteristics of mussel foot protein 5 (Mfp5) and cement precursor protein of the phragmatopoma californica 3 (Pc3) were analyzed, according to which the anionic and cationic peptides with adhesion properties were designed and screened. The adhesive force and adsorption capacity of these peptides were tested by tensile strength testing machine, atomic force microscope (AFM) and Quartz crystal microbalance (QCM). Furthermore, their underlying adhesion mechanisms were analyzed in terms of their compositions and interactions. Results: The anionic and cationic peptides with the purity of over 95% were synthesized using the solid phase peptide synthesis method. The tensile test showed that the adhesive forces of anionic and cationic peptides increased with the extension of curing time, with the highest value reaching 174.04 kPa and 180.11 kPa, respectively. In addition, the adhesive force of the mixed anionic and cationic peptides was significantly enhanced compared to their own adhesive forces, and the adhesive force of their mixture mixed in equal proportions reached 347.81 kPa. The QCM results showed that the adsorption capacity of cationic peptide, and the mixture of both anionic and cationic peptides on gold (Au) surface reached 82.67 ng/cm² and 151.53 ng/cm², respectively. The average microscopic adhesions of anionic and cationic peptides detected by AFM were 5.43 nN and 4.95 nN, respectively, while the average microscopic adhesion of their mixture mixed in equal proportions reached 18.54 nN. Conclusion: The anionic and cationic peptides designed based on mussel and Phragmatopoma californica had certain adhesion properties, which could be significantly increased by electrostatic force mediated complex condensation. Therefore, our study provides a basis for the development of new bionic adhesion materials.