Preparation and antibacterial activity of chitosan microshperes in a solid dispersing system

Abstract

In this study, we investigated the interface contacting inhibition behaviors of chitosan against bacterial in the dispersing state. For that purpose, chitosan microspheres (CMs) in the dispersing state was prepared by the emulsification cross-linking method. The CMs had smooth surface and spherical shape with the diameter of about 124 mm. They were stable after sterilization at 121uC and 150 kPa for 20 min. The CMs had similar antibacterial activity to that of chitosan in the solution form. Their antibacterial activities increased with the increase of the CM concentration, while decreased with the increase of pH of the system. It was found that the CMs with the degree of deacetylation (DD) of 63.6% exhibited the highest antibacterial activity, while the CMs with the DD of 83.7% exerted the lowest antibacterial activity among the three tested samples.

Biomedical Activity of Chitin/Chitosan Based Materials—Influence of Physicochemical Properties Apart from Molecular Weight and Degree of N-Acetylation

“…Helander et al [72] reported that chitosan displayed antibacterial activity not only in an acid environment, although showed a stronger inhibitory effect at lower pHs with the inhibitory activity weakening with increasing pH. Kong et al [73] and Yang et al [74] observed that the antibacterial activity of the N-alkylated chitosan derivatives against E. coli increased as the pH rose from 5.0 reaching a maximum around pH 7.0-7.5. Also, the investigation of the antibacterial property of chitosan microspheres (CM) in a solid dispersing system showed that under neutral conditions, of the three tested CM samples with DA of 2.5, 16.5, 37.4% respectively, the highest inhibitory effect was observed for the CM sample with DA of 37.4% [73].…”

“…Kong et al [73] and Yang et al [74] observed that the antibacterial activity of the N-alkylated chitosan derivatives against E. coli increased as the pH rose from 5.0 reaching a maximum around pH 7.0-7.5. Also, the investigation of the antibacterial property of chitosan microspheres (CM) in a solid dispersing system showed that under neutral conditions, of the three tested CM samples with DA of 2.5, 16.5, 37.4% respectively, the highest inhibitory effect was observed for the CM sample with DA of 37.4% [73]. To date, there has been no positive information about the antimicrobial activity of chitosan under alkaline conditions.…”

“…For the obtained materials such parameters as the degree of quaternization and/or the degree of substitution should be determined and their influence on the investigated biological properties tested, -the biological properties of chitin/chitosan materials used directly in biomedical applications (e.g., antimicrobial effects) could be different that observed for materials obtained after preparation of nanoparticles, microspheres, hydrogels, films, fibers or tablets, -considerable research efforts should be directed towards developing safe and efficient chitin/chitosan-based formulations. As an example, such factors as particle size requirement, the thermal and chemical stability of the active agent, reproducibility of the kinetic release profiles, stability of the final product and residual toxicity associated with the final product depends upon the methods of preparing chitosan-based micro/nanoparticulate drug delivery systems, -the influence of physicochemical properties apart from M W and DA on chitosan-based formulation affecting the delivery of DNA and siRNA [51] and on antimicrobial properties of chitin/chitosan materials [68][69][70][71][72][73][74][85][86][87][88]94,95,104,105] is the best known. For other biological properties our knowledge is still not sufficient, -chitin/chitosan properties are interrelated and many times they could influence the bioactivity in a conflicting manner, e.g., would healing properties and permeation enhancement properties are inevitably linked to other such as mucoadhesion and cytotoxicity.…”

Biocompatibility and characteristics of chitosan/cellulose acetate microspheres for drug delivery

“…Various sustained release drug carriers have been made from chitosan such as films [1][2], microspheres [3][4], nanoparticles [5][6], and gels [7][8]. Chitosan microspheres have been widely investigated for use as controlled release delivery systems for proteins [9], hormones [10], antibiotics [11], vitamin [12], and cells [13].…”

The effect of carboxymethyl-chitosan nanoparticles on proliferation of keloid fibroblast

“…It has caused a wide concern due to its unique biologic activity, such as immune enhancing effect [1], antitumor activity [2,3] and antimicrobial activity [4][5][6][7][8]. Previous research showed that chitosan possesses the characteristics favorable for promoting rapid dermal regeneration and accelerating wound healing [9,10] which were closely related to the collagen secretion and keloid forming.…”