Browsing by Subject "Chitosan"

Now showing 1 - 7 of 7

Open Access
3D printed microfluidic reactor for high throuhput chitosan nanoparticle synthesis
(Chemical and Biological Microsystems Society, 2016) Aşık, M. D.; Çetin, Barbaros; Kaplan, M.; Erdem, Yegan; Saǧlam, N.
The major bottleneck for the commercialization of nanoparticle related technologies is the mass production of the nanoparticles. One approach to overcome this bottleneck is use of microfluidic devices. In this paper, a 3D printed, high throughput micro-reactor that is capable of synthesizing both chitosan and chitosan coated iron oxide nanoparticles is presented.
Open Access
Chitosan coated iron-oxide nanoparticle synthesis using a droplet based microfluidic reactor
(IEEE, 2019-06) Wahab, Malik Abdul; Erdem, E. Yegan
A microfluidic reactor for the synthesis of chitosan coated iron-oxide nanoparticles is described. Tapered double T-junction is used to generate droplets of reactants (iron chloride solution and chitosan solution) which were merged using a pillar array. Third reactant ammonia solution is introduced after the mixing of already merged droplets. Ammonia solution initiates the reaction and precipitates are collected at the outlet. Transmission electron microscope (TEM) imaging along with Fourier transform infrared spectroscopy (FTIR) is used to characterize the nanoparticles. These nanoparticles have applications in nano-medicine where they can be used as drug carriers.
Open Access
Chitosan polysaccharide suppress toll like receptor dependent immune response
(Turkish Society of Immunology, 2015) Tincer G.; Bayyurt, B.; Arıca, Y.M.; Gürsel İ.
Objectives: Chitosan is a widely used vaccine or anti-cancer delivery vehicle. In this study, we investigated the immunomodulatory effect of chitosan/pIC nanocomplexes on mouse immune cells. Materials and methods: Proliferative and cytotoxic features of chitosan were tested via CCK-8 assay on RAW 264. 7. IL-1β production was assessed via ELISA from PEC supernatants. TNF-α, and NO induction from chitosan treated RAW cells detected by ELISA and Griess assay, respectively. mRNA message levels of TLRs and cytokines on macrophages in response to chitosan/pIC nanocomplex treatments were evaluated by RT-PCR. Results: Results revealed that chitosan is non-toxic to cells, however, proliferative capacities of macrophages were reduced by chitosan administration. Mouse PECs treated with chitosan, led to NLRP3 dependent inflammasome activation as evidenced by dose-dependent IL-1β secretion. Chitosan/pIC nanocomplexes did not improve immunostimulatory action of pIC on RAW cells, since TNF-α and NO productions remained unaltered. Expression levels of several TLRs, CXCL-16 and IFN-α messages from mouse splenocytes were down regulated in response to chitosan/pIC nanocomplex treatment. Conclusion: Our results revealed that chitosan is an anti-proliferative and inflammasome triggering macromolecule on immune cells. Utilization of chitosan as a carrier system is of concern for immunotherapeutic applications. © 2015 Turkish Journal of Immunology.
Open Access
Chitosan scaffolds with BMP-6 loaded alginate microspheres for periodontal tissue engineering
(2012) Soran, Z.; Aydin, R.S.T.; Gumusderelioglu, M.
The aim of this study is to develop an effective growth factor releasing scaffold-microsphere system for promoting periodontal tissue engineering. Bone morphogenetic protein-6 (BMP-6)-loaded alginate microspheres in narrow size distribution were produced by optimising electrospraying conditions. The addition of these microspheres to chitosan gels produced a novel scaffold in which not only the pore sizes and interconnectivity were preserved, but also a controlled release vehicle was generated. Loading capacity was adjusted as 50ng or 100ng BMP-6 for each scaffold and the controlled release behaviour of BMP-6 from chitosan scaffolds was observed during seven days. Cell culture studies were carried out with rat mesenchymal stem cells derived from bone marrow in three groups; chitosan scaffolds, chitosan scaffolds containing BMP-6-loaded alginate microspheres and chitosan scaffolds with free BMP-6 in culture medium. Results showed that controlled delivery of BMP-6 from alginate microspheres has a significant effect on osteogenic differentiation. © 2012 Informa UK Ltd All rights reserved.
Open Access
A computational molecular approach on chitosan vehicle for metformin
(ICC, 2019) Mirzaei, M.; Gülseren, Oğuz; Jafari, E.; Aramideh, M.
Density functional theory (DFT) calculations have been performed to study properties of chitosan (Chit) as a possible vehicle for carrying metformin (Met) drug. To this aim, the singular molecules of Met and Chit have been first optimized and, then, sixteen possible bimolecular complexes have been subsequently constructed and optimized to obtaine the stabilized interacting structures. Two bimolecular complexs have been seen as the most powerful interacting systems among all complexes. N5 and N8 atoms of Met are very important atoms for interacting with Chit counterpart. Molecular parameters such as molecular orbital energies and dipole moments approved the effects of interations on both Chit and Met counterparts. Atomic scale quadrupole coupling constants demonstrated the effects of interactions on the electronic atomic sites. As a final remark, although the Chit could be used as a vehicle for Met; further investigations are still required to see what’s happening inside the molecular systems.
Open Access
Immobilization of laccase on itaconic acid grafted and Cu ( II ) ion chelated chitosan membrane for bioremediation of hazardous materials
(Wiley, 2012) Bayramoglu, G.; Gursel, I.; Yilmaz, M.; Arica, M. Y.
Background: Chitosan membranes were formed through a phase inversion technique and then cross-linked with epichlorohydrin (CHX). Heterogeneous graft copolymerization of itaconic acid (IA) onto membrane was carried out with different monomer concentrations (CHX-g-p(IA)). The membrane properties such as equilibrium swelling ratio, porosity, and contact angle were measured, together with analysis by scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), atomic force microscopy (AFM), and Fourier transform infrared (FTIR) spectroscopy. Results: The Cu(II) ion incorporated membranes (i.e. CHX-g-p(IA)-Cu(II)) were used for reversible immobilization of laccase using CHX-g-p(IA) membrane as a control system. Maximum laccase adsorption capacities of the CHX-g-p(IA) and CHX-g-p(IA)-Cu(II) membranes (with 9.7% grafting yield) were found to be 6.3 and 17.6 mg mL -1 membrane at pH 4.0 and 6.0, respectively. The K m value for immobilized laccase on CHX-g-p(IA)-Cu(II) (4.16 × 10 -2 mmol L -1) was 2.11-fold higher than that of free enzyme (1.97 × 10 -2 mmol L -1). Finally, the immobilized laccase was used in a batch system for degradation of three different dyes (Reactive Black 5, RB5; Cibacron Blue F3GA, CB; and Methyl Orange, MO). The immobilized laccase on CHX-g-p(IA)-Cu(II) membrane was more effective for removal of MO dye than removal of CB and RB5 dyes. CONCLUSION: Flexibility of the enzyme immobilized grafted polymer chains is expected to provide easy reaction conditions without diffusion limitation for substrate dye molecules and their products. The support described, prepared from green chemicals, can be used for the immobilization of industrially important enzymes. © 2012 Society of Chemical Industry.
Open Access
Microfluidic device for synthesis of chitosan nanoparticles
(ASME, 2013) Çetin, Barbaros; Taze, Serdar; Asik, M.D.; Tuncel, S.A.
Chitosan nanoparticles have a biodegradable, biocompatible, non-toxic structure, and commonly used for drug delivery systems. In this paper, simulation of a microfluidic device for the synthesis of chitosan nanoparticle is presented. The flow filed together with the concentration field within the microchannel network is simulated using COMSOL Multiphysics® simulation environment. Different microchannel geometries are analyzed, and the mixing performance of these configurations are compared. As a result, a 3D design for a microfluidics platform which includes four channel each of which performs the synthesis in parallel is proposed. Future research directions regarding the fabrication of the microfluidic device and experimentation phase are addressed and discussed. Copyright © 2013 by ASME.