Glutaraldehyde‐crosslinked chitosan beads for controlled release of diclofenac sodium

Abstract

An inexpensive and simple method was adopted for the preparation of chitosan beads, crosslinked with glutaraldehyde (GA), for the controlled release of diclofenac sodium (DS). The beads were prepared by varying the experimental conditions such as pH, temperature, and extent of crosslinking. The absence of any chemical interaction among drug, polymer, and the crosslinking agent was confirmed by FTIR and thermal analysis. The beads were characterized by microscopy, which indicated that the particles were in the size range of 500-700 mm and SEM studies revealed smooth surface and spherical shape of beads. The beads produced at higher temperature and extended exposure to GA exhibited lower drug content, whereas increased drug loading resulted in enhanced drug release.

Formulation and Evaluation of Glutaraldehyde-Crosslinked Chitosan Microparticles for the Delivery of Ibuprofen

“…Approximately equal water sorption values were obtained for microparticles cross-linked with 10 and 20 ml of GST. Water absorption and the rate of water absorption by the microparticles followed the order: GST 25 > GST 30 > GST 20 > GST 15 > GST 10 in SIF while the order in SGF is: GST 15 > GST 30 > GST 25 > GST 20 = GST 10 . It is discernible from Table 1 that the entrapment efficiency of all batches of the microparticles was in the range of 12.90 ± 1.89 % to 23.32 ± 0.97 % with microparticles cross-linked with 10 ml GST recording the highest drug entrapment.…”

“…After 15, 30, 45 and 60 min, GST (2.5 ml each) was added and further stirring was continued for 2 h. The amount of the crosslinking agent was varied from 10 to 30 ml whereas the cross-linking time, stirring speed and the polymer-to-drug ratio were kept constant. Five batches of the microparticles denoted as GST 10 , GST 15 , GST 20 , GST 25 and GST 30 were formulated. Microparticles thus obtained were filtered and washed several times with petroleum ether (boiling point 20 -40 º C) to remove any traces of oil.…”

“…A number of reports have focused on controlling the release of ibuprofen, with some level of success, by entrapping it in microcapsules based on mucoadhesive polymers including sodium alginate, methylcellulose, ethylcellulose, hydroxypropylmethylcellulose and sodiumcarboxymethylcellulose, either in combination or singly [6,7]. Glutaraldehyde cross-linked chitosan has been used by earlier investigators to achieve a controlled release of diclofenac sodium and as a long acting biodegradable delivery vehicle for mitoxantrone [8][9][10]. In those earlier reports, it was shown that drug diffusion from a chitosan matrix could be effectively controlled by cross-linking the matrix using a dialdehyde such as glutaraldehyde.…”

Investigation of polymer dynamics in chitosan-maghemite nanocomposites: a potential green superparamagnetic material

“…Additionally a wide band is observed at 2876-3572 cm −1 . This is due to C-H, N-H and O-H stretching vibrations in chitosan chains [42]. The nanocomposite CF1 did not show any peak at 640 cm −1 .…”

Diffusion of biological molecules through hollow chitosan fibers

“…These new linkages may contribute to decreasing the number of reactive groups (e.g., when amine groups are involved in chelation reactions for the binding of metal cations) and may affect diffusion properties. In the case of gel beads, Kulkarni et al 36 showed that the diffusion of diclofenac (an anti-inflammatory drug) decreased when the gel beads were crosslinked with chitosan. Figure 11 shows the influence of a crosslinking treatment for fibers conditioned by the sucrose-drying procedure.…”