Self Assembly System Of Small Molecular Peptide For Biological Application

Self-assembly system is widespread whether in chemistry, biology or pHysics. Small molecular peptide self-assembly system attracts extensive attentions in academia in recent years, and it is also widely used in cell culture, drug delivery, tissue engineering, immobilization of enzyme.1. Hybrid hydrogel is composited of small molecule and polymer, compared with the small molecular hydrogel, is stiffer and can be cut into different shapes. We studied it in drug delivery, wastewater treatment, the immobilization of enzyme before, but the alkaline pHospHatase immobilized was also involved in gelling process, which makes us adopt the effect of immobilization. Therefore, we adopt a different method of gelling-adding reducing agent, we can further study on the effect of immobilized enzyme to have a bigger breakthrough.2. Gelling method of small molecule is varied, on the basis of previous work, we introduce a kind of four-armed polymer protein. The protein as a crosslinking agent, through the non covalent interaction, delivers the four-armed PEG together to form a hydrogel, it can be used in culture of SD rat bone marrow mesenchymal stem cells. We find that the cell adhesion is in good condition, after a week of culture, the number of cells grows gradually with few dead cell, which may be due to the PEG and protein with good compatibility, providing a good living skeleton.3. In order to generate short peptide-based self-assembly systems or molecular hydrogelators, aromatic capping groups are usually needed including pyren, fluorenyl (Fmoc), napHthalene (Nap), and pHenothiazine (PTZ) groups. However, these aromatic groups can only emit short wavelength UV lights upon excitation, hindering their imaging applications. Herein, we introduce a new type of fluorescent molecule-NBD, surprisingly, the nanofibers formed by NBD capped peptides have different distributions in different cells. Since this arouses our great interest, we begin to study the mechanism to expcet that some combination from various proteins of these nanofibers would lead to the aforesaid pHenomenon, as the conclusion can not be confirmed. Though we do not know the reasons for different cellular distributions, protein binding patterns, we have offered a versatile tool to image cellular distribution of self-assembled nanostructures.