Gel—sol transition in gellan gum solutions. II. DSC studies on the effects of salts

In the present investigation, sodium alginate based multiparticulate system overcoated with time and pH dependent polymer was studied in the form of oral pulsatile system to achieve pulsatile with sustained release of aceclofenac for chronotherapy of rheumatoid arthritis seven batches of micro beads with varying concentration of sodium alginate (2-5 %) were prepared by ionotropic-gelation method using CaCl2 as cross-linking agent. The prepared Ca-alginate beads were coated with 5% Eudragit L100 and filled into pulsatile capsule with varying proportion of plugging materials. Drug loaded microbeads were investigated for physicochemical properties and drug release characteristics. The mean particle sizes of drug-loaded microbeads were found to be in the range 596±1.1 to 860 ± 1.2 micron and %DEE in the range of 65-85%. FT-IR and DSC studies revealed the absence of drug polymer interactions. The release of aceclofenac from formulations F1 to F7 in buffer media (pH 6.8) at the end of 5h was 65.6, 60.7, 55.7, 41.2, 39.2, 27 and 25% respectively. Pulsatile system filled with eudragit coated Ca-alginate microbeads (F2) showed better drug content, particle size, surface topography, in-vitro drug release in a controlled manner. Different plugging materials like Sterculia gum, HPMC K4M and Carbopol were used in the design of pulsatile capsule. The pulsatile system remained intact in buffer pH 1.2 for 2 hours due to enteric coat of the system with HPMCP. The enteric coat dissolved when the pH of medium was changed to 7.4. The pulsatile system developed with Sterculia gum as plugging material showed satisfactory lag period when compared to HPMC and Carbopol.

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Solubility Enhancement of Poorly Water-Soluble Antifungal Drug Acyclovir by Nanocrystal Formulation Approach

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2018.11.2.5 ◽

2018 ◽

Vol 11 (2) ◽

pp. 4036-4042

Author(s):

Prakash Goudanavar ◽

Ankit Acharya ◽

Vinay C.H

Keyword(s):

Chemical Interaction ◽

Research Work ◽

Antiviral Drug ◽

In Vitro Release ◽

Oral Route ◽

Water Soluble ◽

Precipitation Method ◽

Dsc Studies ◽

Ft Ir

Administration of an antiviral drug, acyclovir via the oral route leads to low and variable bioavailability (15-30%). Therefore, this research work was aimed to enhance bioavailability of acyclovir by nanocrystallization technique. The drug nanocrystals were prepared by anti-solvent precipitation method in which different stabilizers were used. The formed nanocrystals are subjected to biopharmaceutical characterization including solubility, particle size and in-vitro release. SEM studies showed nano-crystals were crystalline nature with sharp peaks. The formulated drug nanocrystals were found to be in the range of 600-900nm and formulations NC7 and NC8 showed marked improvement in dissolution velocity when compared to pure drug, thus providing greater bioavailability. FT-IR and DSC studies revealed the absence of any chemical interaction between drug and polymers used.

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Development and Characterization of LBG-PVA Interpenetrating Networks Incorporating Gliclazide for Sustained Release

Current Drug Therapy ◽

10.2174/1574885515999200719143513 ◽

2020 ◽

Vol 15 ◽

Author(s):

Ashish Katoch ◽

Manju Nagpal ◽

Malkiet Kaur ◽

Manjinder Singh ◽

Geeta Aggarwal ◽

...

Keyword(s):

Solid State ◽

Sustained Release ◽

Half Life ◽

Solid State Nmr ◽

Oral Dosage ◽

Cross Linking ◽

Interpenetrating Networks ◽

Dsc Studies ◽

Biological Half Life ◽

Percentage Yield

Background: Controlled oral dosage forms have always been preferred for drugs with variable absorption, and short biological half life and frequent dosing. The prime goal with sustained release systems is to maintain uniform therapeutic blood levels for longer periods of time. Interpenetrating networks (IPNs) have been evidenced as uniform sustained release systems. In current study, polyvinyl alcohol (PVA) and locust bean gum (LBG) based IPNs were developed for the oral sustained release drug delivery of gliclazide (shows variable absorption). Method: The IPNs were synthesized by emulsion cross-linking method using glutaraldehyde (GA) as a cross linking agent. Gliclazide is a potential second generation, short-acting sulfonylurea oral hypoglycemic agent is having a short biological half-life (2-4 h), variable absorption and poor oral bioavailability. Various batches of IPNs were formulated by varying LBG: PVA ratio and evaluated for percentage yield, drug entrapment efficiency (DEE), swelling properties and in vitro drug release studies. Further characterizations were done by Fourier Transform Infrared Spectroscopy (FTIR), C13 Solid state NMR, X-Ray diffraction study (XRD), Scanning electron microscopy (SEM), and Differential scanning microscopy (DSC) studies. Results: The percentage yield, drug entrapment and equilibrium swelling was observed to be dependent on PVA-LBG ratio and GA amount. Sustained release of drug was observed in all IPN formulations (approx 59 - 86% in 8 h in various batches) with variable release kinetics. SEM studies revealed the regular structures of IPNs. FTIR, XRD, C13 Solid state NMR and DSC studies proposed that drug was successfully incorporated into the formed IPNs. Conclusion: IPNs of LBG and PVA can be used as a promising carrier with uniform sustained release characteristics.

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Co-polymerized Gellan Gum: A Carrier for Controlled Drug Delivery

Drug Delivery Letters ◽

10.2174/221030310503160401115805 ◽

2016 ◽

Vol 5 (3) ◽

pp. 151-162

Author(s):

Ranjeet Pareek ◽

Shakuntla Verma ◽

Viney Lather ◽

Deepti Pandita

Keyword(s):

Drug Delivery ◽

Controlled Drug Delivery ◽

Gellan Gum

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Gellan gum biosynthesis in Sphingomonas paucimobilis ATCC 31461: Genes, enzymes and exopolysaccharide production engineering

Journal of Industrial Microbiology & Biotechnology ◽

10.1038/sj/jim/7000266 ◽

2002 ◽

Vol 29 (4) ◽

pp. 170-176

Author(s):

I Sá-Correia ◽

A M Fialho ◽

P Videira ◽

L M Moreira ◽

A R Marques ◽

...

Keyword(s):

Gellan Gum ◽

Sphingomonas Paucimobilis ◽

Production Engineering ◽

Exopolysaccharide Production

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Anti-Inflammatory Properties of Injectable Betamethasone-Loaded Tyramine-Modified Gellan Gum/Silk Fibroin Hydrogels

Biomolecules ◽

10.3390/biom10101456 ◽

2020 ◽

Vol 10 (10) ◽

pp. 1456

Author(s):

Isabel Matos Oliveira ◽

Cristiana Gonçalves ◽

Myeong Eun Shin ◽

Sumi Lee ◽

Rui Luis Reis ◽

...

Keyword(s):

Rheumatoid Arthritis ◽

Mechanical Properties ◽

Silk Fibroin ◽

Therapeutic Efficacy ◽

Composite Structures ◽

Gelation Time ◽

Polymeric Materials ◽

Gellan Gum ◽

Traditional Use

Rheumatoid arthritis is a rheumatic disease for which a healing treatment does not presently exist. Silk fibroin has been extensively studied for use in drug delivery systems due to its uniqueness, versatility and strong clinical track record in medicine. However, in general, natural polymeric materials are not mechanically stable enough, and have high rates of biodegradation. Thus, synthetic materials such as gellan gum can be used to produce composite structures with biological signals to promote tissue-specific interactions while providing the desired mechanical properties. In this work, we aimed to produce hydrogels of tyramine-modified gellan gum with silk fibroin (Ty–GG/SF) via horseradish peroxidase (HRP), with encapsulated betamethasone, to improve the biocompatibility and mechanical properties, and further increase therapeutic efficacy to treat rheumatoid arthritis (RA). The Ty–GG/SF hydrogels presented a β-sheet secondary structure, with gelation time around 2–5 min, good resistance to enzymatic degradation, a suitable injectability profile, viscoelastic capacity with a significant solid component and a betamethasone-controlled release profile over time. In vitro studies showed that Ty–GG/SF hydrogels did not produce a deleterious effect on cellular metabolic activity, morphology or proliferation. Furthermore, Ty–GG/SF hydrogels with encapsulated betamethasone revealed greater therapeutic efficacy than the drug applied alone. Therefore, this strategy can provide an improvement in therapeutic efficacy when compared to the traditional use of drugs for the treatment of rheumatoid arthritis.

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