Synthesis,Properties And Drug Release Of Sugarcane Bagasse Cellulose Based Intelligent Hydrogel

Bagasse is the residue obtained after crushing and extracting juice from sugarcane,which is one of the largest by-products of cellulose industry.Because of the wide cultivation of sugarcane,bagasse waste is regarded as the ideal raw material for the manufacture of new materials because of its low cost,green and renewable.The intelligent hydrogel(environmental sensitive hydrogel)based on cellulose has been widely applied in drug controlled release,biomaterials and wastewater treatment,and has become a hot research topic in recent years.In this paper,several kinds of intelligent hydrogels with environmental sensitivity were prepared by using sugarcane bagasse cellulose(SBC)as the main raw material.The structure and properties of hydrogels were studied,and the potential applications of hydrogels in drug release were discussed.The main contents and results are as follows:1.Bagasse pulp was pretreated with sodium sulfite and potassium hydroxide to remove impurities such as hemicellulose and lignin in bagasse to obtain high purity bagasse cellulose.The results of SEM showed that the surface of untreated raw fiber was compacted,the treated fiber became shorter and softer,and more fine fibers were separated on the surface.2.SBC/CMC hydrogels were prepared by using SBC and carboxymethylcellulose(CMC)as raw materials and dissolved in NaOH/urea aqueous solution system at low temperature,respectively.The epichlorohydrin(ECH)was used as crosslinking agent.Using N-isopropylacrylamide(NIPAm)as a temperature sensitive monomer,SBC and CMC were polymerized to form the first network structure,and the NIPAm was polymerized into a second network in the first network structure by interpenetrating polymer network(IPN).A novel SBC/CMC-NIPAm hydrogel with IPN structure was successfully prepared.The results of SEM and FTIR showed that both SBC/CMC hydrogels and IPN hydrogels were porous,and the two networks exhibited good compatibility and uniform morphology in hydrogels.The existence of the first and second networks were independent of each other.The existence of the first and second networks is independent of each other.The hydrogels have good mechanical strength through compression test.The SBC/CMC(2:1)hydrogel exhibits the best mechanical properties and can withstand the compression stress of 80kpa.By studying the equilibrium swelling ratio and re-swelling ability of hydrogels,the swelling capacities of SBC/CMC hydrogels and IPN hydrogels were tested,and their pH and temperature sensitivity were proved.3.SBC/CMC hydrogel and IPN hydrogel were used as carriers and bovine serum albumin(BSA)was used as drug model.The drug loading and drug release properties of hydrogels were preliminarily studied.Both IPN and non-IPN hydrogels showed break release in the first 60 minutes and then released slowly until equilibrium.The cumulative release of BSA in SGF(pH=1.35)was significantly higher than that in PBS(pH=7.4),which proved the effect of pH sensitivity on drug release.The release of BSA from temperature-sensitive IPN hydrogels containing PNIPAm was very different at different temperatures,and the release amount of BSA at 37? was much larger than that at 23 ?,and the former released more than twice as much as the latter.Moreover,the release amount of IPN hydrogel at 23 ? was only half of the SBC/CMC hydrogel,the structure of IPN hydrogel was denser than that of LCST,which made it more difficult to release BSA into external environment.The effect of temperature sensitivity on drug release was proved.4.Macroporous hydrogels with pH sensitivity were successfully prepared by using SBC and sodium alginate as raw materials.The pore size of SBC/SA hydrogel is larger than that of SBC hydrogel.The chemical reaction took place between the two components of SBC/SA hydrogels to form a whole.The addition of SA reduced the thermal stability of hydrogels.The addition of SA into cellulose hydrogel can significantly increase the pore size and swelling ability of the gel,and the semi-rigid chain of cellulose can provide the supporting pore wall.Through the swelling degree of hydrogel in different pH environment,the swelling ratio of SBC/SA hydrogel has obvious correlation with pH value,indicating that the presence of sodium alginate has pH sensitivity to hydrogel.