Characterization Of The Interaction Of Chitosan And Carboxymethyl Chitosan With Amino Acids And Their Effects On Agglomeration And Bacteriostasis

Chitosan,the only existing natural cationic polysaccharide prepared from the deacetylation of chitin,has been widely applied in various pharmaceutical sectors including drug release,tissue engineering,oncotherapy and high-efficiency antibiotic with its biocompatibility,biodegradability,hemostasis,antibacterial property,antitumor activity and promotion on tissue recovery.With the chitosan nanoparticles used as active ingredients,not only an improvement in its solubility but also a perfect demonstration of the overview of its outstanding bioactivity and biological pharmaceutical properties could be made.Although they are derivatives of chitosan covering a wide range of application prospects,the agglomeration of nano-chitosan and antibacterial activity of carboxymethyl chitosan seriously create technological bottleneck in their applications.In this paper,three amino acids(glycine acid,aspartic acid and arginine acid)were employed as drug carriers to investigate the effect of the interaction of hydrogen bond among amino acids with different chemical structures,chitosan and carboxylmethyl chitosan on agglomeration and antibacterial activity through preparation and characterization of chitosan/amino acid nano-suspension and carboxylmethyl chitosan/amino acid blending solution.In this study,the chitosan/amino acid nano-suspension and carboxylmethyl chitosan/amino acid blending solution were prepared by the high pressure homogenization method while the interaction of hydrogen bonds among different amino acids,chitosan and carboxylmethyl chitosan was studied by the fourier transform infrared spectrometry,comparing trends resulted from different amino acids to hydrogen bonds formed between chitosan and carboxylmethyl chitosan.The agglomeration behavior was carried out through particle size analysis potentiometry and transmission electron microscope,comparing effects of different amino acids on the agglomeration of nano-chitosan.The anti-bacterial activity of the carboxylmethyl chitosan/amino acid blending solution was investigated by the oxford cup agar diffusion method and micro two-fold dilution method,comparing effects of different amino acids on the anti-bacterial activity of the carboxylmethyl chitosan.1.There could exhibit significant hydrogen bond interaction between chitosan or carboxylmethyl chitosan and amino acid.The result of FTIR demonstrated that the carboxymethyl chitosan/glycine were respectively red shifted(21?29 cm-1)and blue shifted(7?12 cm-1),the carboxymethyl chitosan/aspartic were red shifted(23?35 cm-1)and blue shifted(12?18 cm-1),the carboxymethyl chitosan/arginine were red shifted(26?37 cm-1)and blue shifted(14?21 cm-1).It was proved that the interaction of hydrogen bond between arginine acid and carboxymethyl chitosan were the strongest,and the second was carboxymethyl chitosan/aspartic,and the worst 'was carboxymethyl chitosan/glycine.The FTIR demonstrated that the chitosan/glycine were red shifted(17?23 cm-1),the chitosan/aspartic were red shifted(23?37 cm-1),and the chitosan/arginine were red shifted(32?43 cm-1).It was proved that the interaction of hydrogen bond between arginine acid and chitosan were the strongest,and the second was chitosan/aspartic,and the worst was chitosan/glycine.In general,the result of study indicated that there could exhibit significant hydrogen bond interaction between chitosan or carboxylmethyl chitosan and amino acid which was ranked successively as arginine acid,aspartic acid and glycine acid.2.The trend of nanoparticles agglomeration was significantly reduced by adding amino acids.The agglomeration experimentation indicated that the agglomeration trend of chitosan/arginine nanoparticles were the best through the investigation of three months.The growth of chitosan/arginine nanoparticles were the slowest with 290?350 nm in particle size;the chitosan/aspartic nanoparticles were next to it with 340?380 nm;the particle size of the chitosan/glycine nanoparticles were 370?400 um,which grew the fastest.The agglomeration trend manifested that the agglomeration of the nano-chitosan was significantly reduced by adding amino acids(arginine acid>aspartic acid>glycine acid),showing a positive correlation to the hydrogen bond interaction formed within chitosan/amino acids.3.The antibacterial activity of the carboxymethyl chitosan was improved greatly by adding amino acids.The result of antibacterial experimentation manifested that the MIC of carboxymethyl chitosan were 10 mg/mL,which were the largest inhibitory concentration.The MIC of carboxymethyl chitosan/glycine and carboxymethyl chitosan/aspartate were 5 mg/mL,and the MIC of carboxymethyl chitosan/arginine were 2.5 mg/mL.The antibacterial study demonstrated that the antibacterial activity of the carboxylmethyl chitosan was improved greatly by adding amino acids among of which the arginine acid did the best,showing a certain correlation between antibacterial activity and the hydrogen bond interaction.