Preparation And Characterization Of Nanocellulose-based Drug Delivery Materials

Drug Delivery System is achieved by physical or chemical combination between polymer carrier and different types of drugs. The drug were released as constant speed with the diffusion and permeation force, and eventually make the drug efficacy into full play. The drug delivery system contains two kinds of important material: drug delivery carrier material and drug. As the important part of drug delivery system, drug delivery carrier material could control the drug release rate and influence the drug efficacy. Therefore, drug delivery carrier material development becomes a hot topic. Nanocelluose has appealing instinct properties like high mechanical strength, high specific surface area, good rheological properties, and being easily chemical modification and biocompatibility, which has been attract many interest for the use as a drug carrier material applied in medical field such as drug delivery, wound healing.Nanocellulose was prepared by TEMPO alkaline oxidation and high-pressure homogenization treatment with eucalyptus pulp. Nanocellulose as drug carrier and two kinds of antibacterial agent(gentamicin and moxifloxacin) as the drug were investigated to prepare the nanocellulose-based drug delivery film material and nanocellulose-based drug delivery aerogel material with drug slow-release and antibacterial properties. The way of combination between nanocellulose and drug were discussed. The influence of carboxyl content and homogenization runs of obtained nanocellulose on the drug delivery material’s structure, mechanics and drug release performance were studied. The drug release performance of drug delivery material in different environment was discussed. The antibacterial experiments of the material was demonstrated by using standard staphylococcus aureus.The results are showed as follows:1. TEMPO oxidized cellulose with carboxyl content of 1.13-1.70mmol/g were prepared by tuning the dosage of NaClO. Nanocellulose was prepared by the application of oxidized cellulose through high-pressure homogeneous processing. The width of nanocellulose was 3-20 nm, and the length was under 500 nm.2. Nanocellulose prepared under different conditions was mixed with gentamicin and moxifloxacin. The nanocellulose-based drug delivery film was successfully prepared by vacuum filtration. The influence of carboxyl content and homogenization runs of nanocellulose on the mechanical properties and equilibrium swelling ratio of the films were studied. All the drug contained film prepared by using nanocellulsoe with carboxyl content of 1.70 mmol/g and with 8 times homogenization. The elastic modulus and the equilibrium swelling ratio of the gentamicin and moxifloxacin contained film were 7.60 GPa and 3.70, and 3.48 GPa and 3.48, respectively.3. The effect of carboxyl content and homogenization times of nanocellulose on the drug delivery film’s drug release and antibacterial properties were discussed. Drug release properties of film in different pH and salt concentration were also studied. Compared with nanocellulosebased moxifloxacin film, nanocellulose-base gentamicin film has obvious drug release characteristics, that drug release cycles reach 24 h and gentamicin final release rate was 81.46%, when the carboxyl content of nanocellulose is 1.70mmol/g, 8 times homogenization. Gentamicin final release rate were 90.62% and 84.32%, when drug delivery film in the pH = 3 PBS buffer solution and 10mmol/L NaCl. The diameter of the inhibition ring changs from 10 mm to 16 mm according to the nanocellulose delivery film’s preparation conditions.4. Nanocellulose prepared under different conditions was mixed with gentamicin and moxifloxacin.The nanocellulose-based drug delivery aerogel was successfully manufactured by freeze-drying. The influence of carboxyl content and homogenization times of nanocellulose on the drug delivery aerogel’s pore diameter and porosity, mechanical properties and equilibrium swelling ratio were studied. When using nanocelluose with carboxyl content of 1.70mmol/g and with 8 times homogenization, the prepared nanocellulose-based drug delivery aerogel’s pore diameter and porosity were 151 microns and 96.87%, respectively.The compression modulus and the equilibrium swelling ratio were 2.52 MPa and 60.80; respectively. However, the porosity, compression modulus and the equilibrium swelling ratio of nanocellulose-based moxifloxacin aerogel were 98.26%, 2.02 MPa and 61.23, respectively.5. The influence of carboxyl content and homogenization times of nanocellulose on the drug release and antibacterial properties of aerogel were discussed. When nanocellulose’s carboxyl content is 1.70mmol/g, 8 times homogenization, nanocellulose-base gentamicin aerogel’s initial release rate and the final release rate were 39.81% and 76.68% respectively, and the diameter of the inhibition ring around aerogel was 16.98 mm; Both the initial release rate and the final release rate of the nanocellulose based moxifloxacin aerogel were greater than 80%, The diameter of the inhibition ring around aerogel was 8.30 mm. All results showed that nanocellulose-base gentamicin aerogel had better antibacterial properties than that of nanocellulose-base moxifloxacin aerogel.