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A novel bio-based epoxy resin system with rosin-sourced acid anhydrides was established by formula design and selection according to the resin film’s forming performance and state with different storage time. The formula involves epoxy resin/curing agent/accelerator with mass proportion of 100/60/3-4. The curing property and the relationship between viscosity-temperature-time of resin were characterized by dynamic or steady state DSC analysis and cone plate viscometer, respectively. The results show the resin system can be cured at the range of 120-140℃, and the range of hot melt prepreg temperature is 60-85℃ with the viscosity from 1500mPa·s to 5000mPa·s. The processing time of hot melt prepreg is about 180min at 70℃. The curing mechanism of bio-based resin was also investigated through the samples with different curing time by IF and DSC.

Objective: To screen and identify the peptides that specifically bind to CD13 on monocytes., Methods: The phages capable of specific binding to CD13 were screened in the phage-displayed 12-peptide library. The affinity of the selected phages with CD13 was verified with enzyme-linked immunosorbent assay (ELISA). The sequences of the peptides bound to the phages were deduced according to the phage DNA sequences, and the functional peptides aligned using the BLASTP on the Website NCBI were synthesized. To analyze the biological function of the screened peptides, the location of the peptides bound to THP-1 cells was detected using immunofluorescence assay. The blocking effect of WM15 on the peptide binding to THP-1 cells was assessed by immunofluorescence assay., Results: The phages that specifically bound to CD13 were effectively enriched to approach saturation after 4 rounds of panning. The recovery rate in the fourth round was 30 times that in the first round. Twenty selected phages were verified by ELISA, and the signals of 10 phages were higher than the control. The sequences of the peptides P9 and P7 showed 83% and 100% identity with those of human cytomegalovirus (HCMV) UL38 and UL105, respectively. The peptides bound to the cell membrane of THP-1 cells as shown by immunofluorescence assay. The binding of the peptides P9 and P7 to THP-1 cells was blocked by CD13-specific monoclonal antibody WM15 at different levels., Conclusion: Two peptides (P7 and P9) that can specifically bind to CD13 have been screened successfully, and these two peptides show specific binding to CD13 on the membrane of THP-1 cells.