Isolation of a peptide motif for ZrO2-binding

Objectives: The purpose of this study was to create peptide motif that has affinity to the surface of Zirconia in terms of tissue-implant interface. Methods: Zirconia binding peptide motif was created using a peptide phage displaying system (Ph-D system, New England Biolabs). Particles (average diameter was 125um) of yttria stabilized zirconia (YSZ) were obtained from TOSOH (Tokyo, Japan) and used as target in the selection experiments. QCM-D (Q-sense, Gothenburg) was used to monitor binding of phages to zirconia. Data was analyzed with Welch's t-test. Results: Starting from a library of phage displaying random sequence of 12-mer peptide, we repeated cycles of binding, washing, eluting and re-amplification against YSZ particles. After four cycles, we found that several phage clones enriched in the elutant. One of them, φ#17 was further characterized in this study. DNA sequencing the corresponding portion of φ#17 has unexpectedly revealed that the phage displayed 58-mer peptide (instead of 12-mer). We found that φ#17 had 300 fold significant higher binding ability (P< 0.05) compared to the phage displaying no peptide. To rule out the possibility that the phage recognized yttria portion but not zirconia, we evaluated the phage binding to zirconia sensor of QCM (that didn't contain yttria). Previous study indicated that the rapid increase in dissipation occurs when a phage binds to a sensor via its displayed peptide (Sano & Shiba, JACS 125:14234, 2003). Similar rise in dissipation was observed from φ#17 but not from a control phage, indicating that φ#17 can binds to the surface of zirconia via its displayed peptide. Conclusion: We successfully created peptide binding motif against Zirconia.