Preparation of chitosan nanoparticles by spray drying and their antibacterial activity

[[abstract]]Chitosan nanoparticles were prepared from chitosan with different molecular weight by spray drying method. The morphology of chitosan nanoparticles were characterized by SEM and size distribution and zeta potential values were determined. Effect of chitosan solution concentrations, molecular weight of chitosan (MMW, HMW and VHMW) and size of spray dryer nozzles on average size, size distribution and zeta potential values of chitosan nanoparticles were investigated. Moreover, the effect chitosan nanoparticles and chitosan nanoparticles/amoxicillin complex on Staphylococcus aureus was also tested. The results showed that the average size of chitosan nanoparticles were in the range of 95.5 to 395 nm and zeta potential values of 39.3 to 45.7 mV depended on concentration and molecular weight of chitosan. The lower concentration and molecular weight of chitosan were used, the smaller size of chitosan nanoparticles and the higher zeta potential values were obtained. The testing for antibacterial activity against S. aureus indicated that chitosan nanoparticles strongly inhibited the growth of bacteria with the minimum inhibitory concentration (MIC) of 20µg/mL, which were lower than that of chitosan solution and amoxicillin. The antibacterial capacity of chitosan nanoparticles also depended on size, zeta potential values and molecular weight of chitosan. Complex of chitosan nanoparticles/amoxicillin could improve antibacterial activity of amoxicillin.[[notice]]補正完畢[[incitationindex]]SCI[[booktype]]紙本[[booktype]]電子

Preparation of chitosan nanoparticles by TPP ionic gelation combined with spray drying, and the antibacterial activity of chitosan nanoparticles and a chitosan nanoparticle–amoxicillin complex

[[abstract]]Chitosan nanoparticles were prepared from chitosan with various molecular weights by tripolyphosphate (TPP) ionic gelation combined with a spray drying method. The morphologies and characteristics of chitosan nanoparticles were determined by TEM, FE-SEM and from their mean sizes and zeta potentials. The effect of chitosan molecular weight (130, 276, 760 and 1200 cPs) and size of spray dryer nozzle (4.0, 5.5 and 7.0 µm) on mean size, size distribution and zeta potential values of chitosan nanoparticles was investigated. The results showed that the mean size of chitosan nanoparticles was in the range of 166–1230 nm and the zeta potential value ranged from 34.9 to 59 mV, depending on the molecular weight of chitosan and size of the spray dryer nozzles. The lower the molecular weight of chitosan, the smaller the size of the chitosan nanoparticles and the higher the zeta potential. A test for the antibacterial activity of chitosan nanoparticles (only) and a chitosan nanoparticle–amoxicillin complex against Streptococcus pneumoniae was also conducted. The results indicated that a smaller chitosan nanoparticle and higher zeta potential showed higher antibacterial activity. The chitosan nanoparticle–amoxicillin complex resulted in improved antibacterial activity as compared to amoxicillin and chitosan nanopaticles alone. Using a chitosan nanoparticle–amoxicillin complex could reduce by three times the dosage of amoxicillin while still completely inhibiting S. pneumoniae.[[notice]]補正完

Nanomaterials in drug delivery system

In this article, nanomaterials that are currently being investigated for their potentials in biomedical field and have established to be drug carriers are elaborated. Liposome for example, has already been utilised in biomedical applications for a long time ago but extensive studies are still conducted in order to optimize its properties for better results. Each nanomaterials discussed in this article exhibits unique physiochemical and biological characteristics which give them flexibility to be used in many applications. Some exist as natural nanomaterials such as liposome, while some can be synthesized from certain compounds. Some nanomaterials can be functionalized to enhance their efficiency as drug carriers. However, not all synthetic nanomaterials are safe to be consumed by human. Therefore, further investigations and evaluations of each nanomaterial in term of long term effect in vivo must be carried out