1,383 research outputs found
Recyclable Synthesis, Characterization, and Antimicrobial Activity of Chitosan-based Polysaccharide Composite Materials
We have successfully developed a simple and totally recyclable method to synthesize novel, biocompatible, and biodegradable composite materials from cellulose (CEL) and chitosan (CS). In this method, [BMIm+Cl−], an ionic liquid (IL), was used as a green solvent to dissolve and synthesize the [CEL+CS] composites. Since, the IL can be removed from the composites by washing them with water, and recovered by distilling the washed solution, the method is totally recyclable. Spectroscopic and imaging techniques including XRD, FTIR, NIR, and SEM were used to monitor the dissolution, to characterize and to confirm that CEL and CS were successfully regenerated. More importantly, we have successfully demonstrated that [CEL+CS] composite is particularly suited for many applications including antimicrobial property. This is because the composites have combined advantages of their components, namely superior chemical and mechanical stability (from CEL) and bactericide (from CS). Results of tensile strength measurements clearly indicate that adding CEL into CS substantially increase its tensile strength. Up to 5× increase in tensile strength can be achieved by adding 80% of CEL into CS. Results of in vitro antibacterial assays confirm that CS retains its antibacterial property in the composite. More importantly, the composites reported here can inhibit growth of wider range of bacteria than other CS-based materials prepared by conventional methods; that is over 24 h period, the composites substantially inhibited growth of bacteria such as MRSA, VRE, S. aureus, E. coli. These are bacteria that are often found to have the highest morbidity and mortality associated with wound infections. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013
Facile Synthesis, Characterization, and Antimicrobial Activity of Cellulose-Chitosan-Hydroxyapatite Composite Material: A Potential Material for Bone Tissue Engineering
Hydroxyapatite (HAp) is often used as a bone-implant material because it is biocompatible and osteoconductive. However, HAp possesses poor rheological properties and it is inactive against disease-causing microbes. To improve these properties, we developed a green method to synthesize multifunctional composites containing: (1) cellulose (CEL) to impart mechanical strength; (2) chitosan (CS) to induce antibacterial activity thereby maintaining a microbe-free wound site; and (3) HAp. In this method, CS and CEL were co-dissolved in an ionic liquid (IL) and then regenerated from water. HAp was subsequently formed in situ by alternately soaking [CEL+CS] composites in aqueous solutions of CaCl2 and Na2HPO4. At least 88% of IL used was recovered for reuse by distilling the aqueous washings of [CEL+CS]. The composites were characterized using FTIR, XRD, and SEM. These composites retained the desirable properties of their constituents. For example, the tensile strength of the composites was enhanced 1.9 times by increasing CEL loading from 20% to 80%. Incorporating CS in the composites resulted in composites which inhibited the growth of both Gram positive (MRSA, S. aureus and VRE) and Gram negative (E. coli and P. aeruginosa) bacteria. These findings highlight the potential use of [CEL+CS+HAp] composites as scaffolds in bone tissue engineering
The Role of Technology in Enabling Sales Support
The purpose of this research is to develop a framework explaining how technology can enable sales support. Sales support technology is often used to assist salespeople with a variety of transaction activities, such as prospecting, communicating, scheduling appointments, and processing orders. Sales support technology can be categorized as automation and facilitative technology. Our framework explains when a technology is appropriate for a particular sales activity based on workload and customization. It also proposes who should use a technology based on orientation towards sales revenue or cost control goals. Then, we develop managerial recommendations and propose directions for future research
Inclusive Education: Perceptions of Parents of Children with Special Needs of the Individual Program Planning Process
In inclusive education, students with special needs may access the curriculum through adapted or individualistic plans. Parental involvement in developing the individualistic plans is pertinent to the success of both their children’s education and the plan itself. Research from the United States offers insight into how parents perceive the process of developing individualist plans; however, limited research has been conducted with parents of children with special needs in Canada. This current study examines parental perceptions concerning the Individual Program Planning (IPP) process in Nova Scotia, Canada. Eight parents were interviewed using a guided interview format that consisted of 16 questions based on prior research on the subject matter. Qualitative analysis of the eight interviews resulted in the emergence of four key themes: a) Educator-Parent Communication, b) Parental Perception of Educational Climate, c) Parent Knowledge, and d) Improvements to the IPP process. Each category is reviewed here and supported with samples of direct quotations from parent interviewees. Recommendations are then suggested for educators and parents of children with special needs to promote positive and productive Individual Program Planning meetings
Cellulose-Chitosan-Keratin Composite Materials: Synthesis, Immunological and Antibacterial Properties
Novel composites were synthesized from keratin (KER), cellulose (CEL) and chitosan (CS). The method is recyclable because majority (\u3e88%) of [BMIm+Cl-], an ionic liquid (IL), used as the sole solvent, was recovered for reuse. Experimentally, it was confirmed that unique properties of each component remain intact in the composites, namely bactericide (from KER and CS) and anti-inflammatory property (from KER). Specifically, the composites were examined for their anti-inflammatory influence on macrophages. The cells were imaged and immunophenotyped to determine the quantity using the macrophage marker CD11b. The 75:25 [KER+CS] composite was found to have the least amount of CD11b macrophages compared to other composites. Bactericidal assays indicated that all composites, except the 25:75 [KER+CS], substantially reduce the growth of organisms such as vancomycin resistant Enterococcus (VRE) and Eschericia coli. The results clearly indicate that the composites possess all properties needed for effective use as a wound dressin
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