The specific interaction between sense and antisense peptides was studied by high-performance affinity chromatography (HPAC) and quartz crystal microbalance (QCM) biosensor. Fragment 1-14 of human interferon-β (hIFN-β) was chosen as sense peptide and its three antisense peptides (AS-IFN 1, AS-IFN 2, and AS-IFN 3) were designed according to the degeneracy of genetic codes. The affinity column was prepared with sense peptide as ligand and the affinity chromatographic behavior was evaluated. Glu-substituted antisense peptide (AS-IFN 3) showed the strongest binding to immobilized sense peptide at pH 7.5. A quartz crystal microbalance-flow injection analysis (QCM-FIA) system was introduced to investigate the recognition process in real-time. The equilibrium dissociation constants between sense peptide and AS-IFN 1, AS-IFN 2 and AS-IFN 3 measured 2.08×10-4, 1.31×10-4 and 2.22× 10-5 mol/L, respectively. The mechanism study indicated that the specific recognition between sense peptide and AS-IFN 3 was due to sequence-dependent and multi-modal affinity interaction.
LUO Jia HUANG YanYan XIONG ShaoXiang LIU GuoQuan ZHAO Ruit
A monolithic molecularly imprinted polymer(monolithic MIP) for trimethoprim(TMP) was prepared by in situ polymerization method as the HPLC stationary phase. Methacrylic acid(MAA) and ethylene glycol dimethacrylate(EDMA) were used as functional monomer and cross-linker, respectively. The obtained MIP monoliths were characterized by high performance liquid chromatography and scanning electron microscope. The SEM analysis result clearly shows that many macropores and flow-through pores were embedded in the network skeleton of the TMP-imprinted monolith, which allowed the mobile phase to flow through the monolithic MIPs with a very low flow resistance. When the flow rate was high to 9.0 mL/min, the backpressure was only 11.1 MPa. Moreover, the imprinting factor was up to 10.3, which demonstrates that the obtained monolithic MIP showed a strong affinity and selectivity to the template molecule.