Synthesis And Applications Of Glycopolymer Modified Gold Nanomaterials

Carbohydrates have good degradable and hydrophilic.They are not only the main energy source for various physiological activities of human life,but also important information transmission factors,so they have important biological functions in some life activities,such as cell proliferation,recognition,differentiation and etc.Gold nanoparticles have many advantages such as small particle size,large specific surface area and easy surface modification,which make it have unique physical,chemical and optical properties.However,gold nanomaterials have poor stability and are easy to aggregate in complex environments.Glycopolymer-functionalized gold nanomaterials could improve the stability of gold nanomaterials and also have the characteristics of both carbohydrates and nanomaterials,which make it a kind of nanoparticle with multifunctional biological activity and important applications in biosensing and disease diagnosis.In this paper,three kinds of gold nanomaterials modified by glycopolymers with different structures and properties were prepared,and their molecular structures and properties were studied.This paper includes:1,In the chapter 2,poly?gluconamidoethyl methacrylate?functionalized gold nanoparticles?PGAMA@AuNPs?with different chain lengths were synthesized by reversible addition-fragmentation chain transfer polymerization?RAFT?,reduction reaction and the interaction of Au-S.The molecular structures and physical properties of PGAMA and PAMAM@AuNPs were characterized by ¹H NMR,FT-IR,XRD and etc.The recognition ability of the PGAMA@AuNPs with Concanavalin A?Con A?was analyzed by surface plasmon resonance characteristics?SPR?and turbidimetric method.The study found that with the addition of Con A,the color of PGAMA@AuNPs gradually changed from red to purple and the UV-spectrum shifted red in plasmon band.In addition,the recognition ability of the PGAMA@AuNPs is related to the molercular weight of glycopolymer on the surface of AuNPs.With the increased of molercular weight of glycopolymer,the dissociation constant became smaller and the interactions between PGAMA@AuNPs and Con A became stronger.Therefore,the PGAMA@AuNPs may be used as biosensor for the detection of Con A by naked eye.2,In the chapter 3,poly?gluconamidoethyl methacrylate?-b-poly?N-isopropylacrylamide?functionalizedgoldnanoparticles?PGAMA-b-PNIPAAm@AuNPs?was synthesized by RAFT polymerization,reduction reaction and the interaction of Au-S.The molecular structures and physical properties of PGAMA-b-PNIPAAm and PGAMA-b-PNIPAAm@AuNPs were characterized by ¹H NMR,FT-IR,XRD and etc.The thermoresponsive of PGAMA-b-PNIPAAm@AuNPs and the recognition ability of PGAMA-b-PNIPAAm@AuNPs with Con A were analyzed.The study found that the low critical solution temperature?LCST?of PGAMA-b-PNIPAAm@AuNPs would be higher than PGAMA-b-PNIPAAm.It was also found that the specific recognition could be achieved only when the temperature is higher than the LCST.The PGAMA-b-PNIPAAm@AuNPs have both temperature sensitivity and specific recognition of Con A,so it can be applied in biosensing and drug loading.3,In the chapter 4,a series of glycosylated AuNCs-cored PAMAM dendrimers?PAMAM-D_m-Lac@AuNCs,m=1,2,3?were successfully fabricated by michael addition reaction,ring-opening polymerization of lactone and the interaction of Au-S.The molecular structures and physical properties of PAMAM-D_m-Lac and PAMAM-D_m-Lac@AuNCs were characterized by ¹H NMR,FT-IR,UV-Visible absorptiometry and etc.The temperature sensibility and recognition ability of the PAMAM-D_m-Lac@AuNCs with Ricinus communis agglutinin(RCA₁₂₀)were analyzed.The results showed that PAMAM-D_m-Lac@AuNCs were temperature-sensitive and their fluorescence intensity decreases with the increase of temperature,among which PAMAM-D₃-Lac@AuNCs decreases most.In the specificity recognition of RCA₁₂₀,it was found that with the increase of PAMAM-D_m-Lac@AuNCs generations,the recognition ability became stronger and the fluorescence intensity also strengthened.These results indicated that the obtained PAMAM-D_m-Lac@AuNCs could be used as biosensors for the detection of RCA₁₂₀.