sodium alginate

In the present investigation efforts were made to develop Misoprostal loaded microspheres to obtain a desirable drug release profile by Ionic gelation method using hydrophilic polymers and cross linking agent to decrease the gastric irritation and to enhance the drug penetration. Microspheres were prepared by using sodium alginate and calcium chloride in different ratios.  All the microspheres were evaluated for particle size, percentage yield, drug entrapment efficiency, stability studies and for in vitro release kinetics and found to be within the limits. Among all the formulations S7 was selected as optimized formulation based on the physico chemical properties and drug release studies. In vitro drug release study of formulation S7 showed 97.17% drug release up to 12h in a controlled manner, which is essential for an anti ulcer therapy. The innovator Misoprostal marketed product shows the drug release of 95.23 in 1 h. The drug release of optimized formulation S7 followed zero order release and Higuchi kinetics indicating diffusion controlled drug release. FT- IR study showed no drug excipient interaction takes place.

The present research paper focuses on designing not only the sustained release tablets of acyclovir to ensure time-dependent, sustained release formulation but also studying the effect of sodium alginate, Xanthan gum and HPMCV K15 on the in vitro release profile of the tablet. The initial release of drug from these matrices occurs by the drug dissolution in the water penetrated into the matrix. The overall drug release from these matrices is governed by hydration, gel layer formation and drug diffusion into the gel layer and to the dissolution media. The formulations ACL1 to ACL5 are containing 200mg of drug with a combination of different excepients. The drug release showed in ACL1 was 95.78%, for only 10hrs and ACL2 showed 90.66% within 11hrs because there was less presence of Xanthan Gum. The Acyclovir tablets of ACL3 showed 91.35% in 12hrs, ACL4 and ACL5 showed drug release of 95.33% for 8hrs and 95.85% for 9hrs. In further formulations the dose of Acyclovir was increased to 400mg ACL6 to ACL10 that are containing combination of excipients. The drug release for the formulations ACL6 showed a drug release of 97.44% for 10hrs and ACL7 showed a drug release 92.4% for 11hrs. From these twelve formulations it was concluded that increase in concentration of Xanthan Gum and Sodium alginate overrun the effect of HPMC K15. The dissolution characteristics allowed for drug to be released in a controlled manner, highlighting the importance for the correct selection of polymers according to their physical, mechanical and pharmacokinetic properties.

The present study deals with the formulation of multiple type floating beads of Ofloxacin to prolong gastric residence time (upto 24 hours) for slow and complete release in stomach and to provide sustained release action. Since, its solubility and absorption is better in the upper part of GI tract, so it was proposed to prepare floating beads of Ofloxacin to localize the drug at its maximum absorption site. Floating beads were prepared by drop wise addition of 3%, 4%, or 5% w/v Sodium Alginate solution containing drug and different gas forming agents or oils, into Calcium chloride solution 1% w/v in glacial acetic acid (10%) using 21 G needle.  The solution containing suspended beads were stirred with magnetic stirrer for 10 minutes to improve the mechanical strength of beads and allowed to complete the reaction to produce gas.  The fully formed beads were collected, washed with ethanol and distilled water and subsequently dried. Different oils such as Peppermint oil and Light liquid paraffin were used in the ratio of 3:5, 3:10, 3:15, and 3:20 respectively. The beads were evaluated for average diameter of beads, lag time, duration of floating drug entrapment efficiency, percent drug loading, floating time and in-vitro drug release in fasted and fed state. As we increased the concentration of polymer and oils, the diameter of beads increases taking all the parameters such as drug ratio, curing agent, curing time, needle nozzle size, dropping rate and height of needle from calcium chloride solution to be constant. The gastric retention of sodium alginate floating beads was best found to be using 20% light liquid paraffin. Also the lag time at this concentration was found to be zero thus leading to float into stomach for upto 24 hours. The drug release profile was best observed in using 4% of sodium alginate polymer and it was 92.719% in 20 hours. Keywords-floating beads, ionotropic gelation, beads size, effervescent system, sodium alginate

For the evaluation of the wound healing activity polymer composite films were prepared by using Chitosan and in combination with Sodium CMC with and without glutaraldehyde were prepared by solvent casting method. Mupirocin was incorporated into selected polymeric films. All the polymeric composite films were characterized by IR study suggested that there was no chemical reaction has taken place, only ionic complexes were formed. All the films were evaluated for thickness, folding endurance and tensile strength. The thickness of all the films was uniform,The folding endurance suggested good flexibility of the films as propylene glycol was used as a plasticizer, Films shown good tensile strength  necessary for better handling . The water vapour penetration suggested that films without cross linker absorbs more moisture compared to films containing cross linking agent. The presence of cross linking agent shown optimum bio-adhesion. All the polymer composite films were evaluated for in vitro swelling study. The films showed good swelling in water more than 6 hrs retaining the shape of the films. The addition of cross linking agent decreased the swelling. Selected polymer composite films were evaluated for in vivo wound healing activity. All the polymeric films showed more than 80% reduction in wound contraction. The mupirocin loaded polymeric composite containing Sodium CMC, shown more than 95% of reduction in wound area after 12 day. Hence it can be concluded that polymer composite films of chitosan-alginate containing mupirocin along with Sodium CMC showed good wound healing and could be used in effective management of wound.

The major problems associated with the anti-tubercular (TB) drug therapy include loss of efficacy through bacterial resistance, side effects, low patient compliance and duration and complexity of treatment. The present study attempts to confront them through a combined approach consisting of microspheres and bioenhancers. Microspheres containing rifampicin were prepared by emulsification technique using stearic acid as a cross-linking agent. Extract of Carum carvi were added as a bioenhancer in variable amount of 5 to 15 mg for each dose of rifampicin. The loading efficiency and release behavior of loaded microparticles were found to be dependent on the cross-linker concentration, cross-linking time and drug-polymer ratio. Prolonged release of the drug from the microspheres was demonstrated in a simulated intestinal fluid. In-vitro release of rifampicin from the microspheres containing 15 mg of bioenhancer showed significant increase in release profile (87.42% in formulation containing bioenhancer against 51.41% for the formulation without bioenhancer) and the release rates were reduced upon increasing the amount of cross-liking agent and prolonging the cross-linking time.

Nasal delivery protects drugs like salbutamol sulphate (SS) from hepatic first-pass metabolism. The study aimed to formulate mucoadhesive sodium alginate (SA) microspheres loaded with (SS) by emulsion cross-linking, with mucoadhesive polymers, for potential nasal delivery by-passing first-pass metabolism. Relevant physichochemical properties, in vitro release and irritation in rabbits were investigated. Stirring rate and cross-linking time affected microsphere parameters. Microspheres were spherical in shape, discrete, with smooth and porous properties favorable for intranasal absorption with high drug-loading of 78.7 %. Mixed-polymers microspheres exhibited higher degree of swelling. Kinetic analysis of release data showed a case II release kinetics for alginate microspheres, and anomalous mechanism for other mixed-polymers formulae. Pronounced sustained drug release over 8 hours was exhibited upon incorporation of Carbopol® 934 and Hydroxypropyl methyl cellulose. The formulated microspheres showed high swelling ability and good mucoadhesion, offering a good potential for future in vivo study to confirm safety and avoidance of first-pass metabolism.