Microencapsulation Approach for Orally Extended Delivery of Glipizide: In vitro and in vivo Evaluation

Polydimethylsiloxane Organic-Inorganic Composite Drug Reservoir with Gliclazide

A novel organic-inorganic gliclazide-loaded composite bead was developed by an ionic gelation process using acidified CaCl2, chitosan and tetraethylorthosilicate (TEOS) as a crosslinker. The beads were manufactured by crosslinking an inorganic silicone elastomer (-OH terminated polydimethylsiloxane, PDMS) with TEOS at different ratios before grafting onto an organic backbone (Na-alginate) using a 32 factorial experimental design. Gliclazide's encapsulation efficiency (EE%) and drug release over 8 h (% DR 8 h) were set as dependent responses for the optimisation of a pharmaceutical formula (herein referred to as 'G op') by response surface methodology. EE % and %DR 8 h of G op were 93.48% ± 0.19 and 70.29% ± 0.18, respectively. G op exhibited a controlled release of gliclazide that follows the Korsmeyer-Peppas kinetic model (R2 = 0.95) with super case II transport and pH-dependent swelling behaviour. In vitro testing of G op showed 92.17% ± 1.18 cell viability upon testing on C2C12 myoblasts, indicating the compatibility of this novel biomaterial platform with skeletal muscle drug delivery.

Sodium alginate-based drug delivery for diabetes management: A review

Diabetes mellitus (DM) is among the biggest global health problems of the 21st century, which is characterised by insufficient insulin secretion and results in the augmentation of blood sugar levels. The current foundation of hyperglycemia therapy is oral antihyperglycemic medications like biguanides, sulphonylureas, α-glucosidase inhibitors, peroxisome proliferator-activated receptor gamma (PPAR-γ) agonists, sodium-glucose co-transporter 2 (SGLT-2) inhibitors, dipeptidyl peptidase-4 (DPP-4) inhibitors and others. Many naturally occurring substances have shown promise in treating hyperglycemia. Inadequate prologitivity of action, restricted bioavailability, site specificity, and dose-related side effects are some problems with currently available anti-diabetic medications. Sodium alginate has shown promise as a drug delivery mechanism, potentially solving issues with current therapies for several substances. This review summarizes the research on the efficacy of drug delivery systems based on alginate for transporting oral hypoglycemic medicines, phytochemicals, and insulin for treating hyperglycemia.

Mucoadhesive microspheres of glutaraldehyde crosslinked mucilage of Isabgol husk for sustained release of gliclazide

Mucoadhesive microspheres have their own significant amongst the various sustained release drug delivery systems. The prolonged residence time of these delivery devices at drug absorption site results in steep concentration gradient and enhanced bioavailability. In this study, the mucilage of Isabgol husk was applied as polymeric backbone to develop gliclazide loaded microspheres by crosslinking with glutaraldehyde. The formulations were studied for surface morphology, swelling behavior, particle size, in vitro release, release kinetics, in vitro mucoadhesion and gamma scintigraphy in rabbits. The release of gliclazide from microspheres was controlled by swelling of crosslinked microspheres followed by diffusion. Gamma scintigraphic images acquired for microspheres retention in gastrointestinal track of rabbits indicated the residence of formulation upto 24 h after oral administration. Gliclazide retained its integrity in polymeric matrix of microspheres as observed by Fourier transform infrared spectroscopy, differential scanning calorimetry and powder X-ray diffractometry. The sustained release of gliclazide and prolonged retention of microspheres in gastrointestinal track disclosed the rationality of mucoadhesive Isabgol husk microspheres in controlling the hyperglycemia in diabetes.

Role of metformin in various pathologies: state-of-the-art microcapsules for improving its pharmacokinetics

Metformin was originally derived from a botanical ancestry and became the most prescribed, first-line therapy for Type 2 diabetes in most countries. In the last century, metformin was discovered twice for its antiglycemic properties in addition to its antimalarial and anti-influenza effects. Metformin exhibits flip-flop pharmacokinetics with limited oral bioavailability. This review outlines metformin pharmacokinetics, pharmacodynamics and recent advances in polymeric particulate delivery systems as a potential tool to target metformin delivery to specific tissues/organs. This interesting biguanide is being rediscovered this century for multiple clinical indications as anticancer, anti-aging, anti-inflammatory, anti-Alzheimer's and much more. Microparticulate delivery systems of metformin may improve its oral bioavailability and optimize the therapeutic goals expected.

Synergistic effect of novel chitosan combined metformin drug on streptozotocin-induced diabetes mellitus rat

Metformin is widely used as a frontline medicine of type-II diabetes. Frequent overdose side-effects and their consequent adversative need to be reduced. The novel source of marine hydrozoa, Thyroscyphus ramosus derived chitosan combined metformin drug was administrated to evaluate the antidiabetic potential on a high-fat diet (HFD) with streptozotocin (STZ) induced diabetic rats. The primary analysis of In vitro antioxidant activity was tested for various solvent dissolved chitosan. Based on their IC₅₀ dose values, CsnAA was chosen for further experiments. The chitosan was combined with metformin by sonication and confirmed through XRD, FTIR and SEM analysis. The enhanced activity was observed in 100 mg/kg metformin combined with CSN500mg/kg. The level of serum bilirubin, total protein, SGH, liver glycogen, Glucose-6-phosphatase and fructose-1,6- phosphatase values were significantly similar to metformin 300 mg/kg treated group. With this beneficiary, the novel chitosan was recommended to administrate with metformin to improve the drug efficacy and reduction of overdose lethal effects.

BÜCHI nano spray dryer B-90: a promising technology for the production of metformin hydrochloride-loaded alginate-gelatin nanoparticles

The current study aimed to formulate gelatin/sodium alginate nanoparticles utilizing BÜCHI nano spray dryer B-90. Nanoparticles possess many of the advantages including new routes of drug administrations and sustained release properties. Utilizing B-90 technology, metformin hydrochloride (MET) nanoparticles were successfully developed. Preformulation studies such as atomization head mesh size, flow rate, head temperature, polymer viscosity, and surface tension, were adjusted. Additionally, post-formulation characters such as particle size, flowability, surface scan, and dissolution profiles, were evaluated. Spray head (7 µm hole), flow rate (3.5 ml/min) and head temperature (120 °C) were optimized. Polymer viscosity was less than 11.2 cP with a surface tension less than 70.1 dyne/cm. Moreover, anti-diabetic effects of MET formulations were evaluated in streptozotocin-induced diabetic rats. Here, discrete, non-aggregated free-flowing nanoparticle powders with a particle size less than 850 nm were generated. Gelatin/sodium-alginate (1:3) produced nanoparticles were successfully sustained by the in vitro release profile of the drug. In vivo evaluations of the previous formula showed a significant reduction of blood glucose level over 24 h. In conclusion, Nano Spray Dryer B-90 (Büchi Labortechnik AG, Flawil, Switzerland) offers a promising technology for nanoparticles formulation as controlled drug delivery systems enhancing compliance of type-II diabetic patients.

Preparation and characterization of alginate and gelatin microcapsules containing Lactobacillus rhamnosus

This paper describes the preparation and characterization of alginate beads coated with gelatin and containing Lactobacillus rhamnosus. Capsules were obtained by extrusion method using CaCl2 as cross linker. An experimental design was performed using alginate and gelatin concentrations as the variables investigated, while the response variable was the concentration of viable cells. Beads were characterized in terms of size, morphology, scanning electron microscopy (SEM), moisture content, Fourier Transform Infrared Spectrometry (FTIR), thermal behavior and cell viability during storage. The results showed that the highest concentration of viable cells (4.2 x 109 CFU/g) was obtained for 1 % w/v of alginate and 0.1 % w/v of gelatin. Capsules were predominantly spherical with a rough surface, a narrow size distribution ranging from 1.53 to 1.90 mm and a moisture content of 97.70 ± 0.03 %. Furthermore, FTIR and thermogravimetric analysis indicated an interaction between alginate-gelatin. Cell concentration of alginate/gelatin microcapsules was 105 CFU/g after 4 months of storage at 8 oC.

Probucol release from novel multicompartmental microcapsules for the oral targeted delivery in type 2 diabetes

In previous studies, we developed and characterised multicompartmental microcapsules as a platform for the targeted oral delivery of lipophilic drugs in type 2 diabetes (T2D). We also designed a new microencapsulated formulation of probucol-sodium alginate (PB-SA), with good structural properties and excipient compatibility. The aim of this study was to examine the stability and pH-dependent targeted release of the microcapsules at various pH values and different temperatures. Microencapsulation was carried out using a Büchi-based microencapsulating system developed in our laboratory. Using SA polymer, two formulations were prepared: empty SA microcapsules (SA, control) and loaded SA microcapsules (PB-SA, test), at a constant ratio (1:30), respectively. Microcapsules were examined for drug content, zeta potential, size, morphology and swelling characteristics and PB release characteristics at pH 1.5, 3, 6 and 7.8. The production yield and microencapsulation efficiency were also determined. PB-SA microcapsules had 2.6 ± 0.25% PB content, and zeta potential of -66 ± 1.6%, suggesting good stability. They showed spherical and uniform morphology and significantly higher swelling at pH 7.8 at both 25 and 37°C (p < 0.05). The microcapsules showed multiphasic release properties at pH 7.8. The production yield and microencapsulation efficiency were high (85 ± 5 and 92 ± 2%, respectively). The PB-SA microcapsules exhibited distal gastrointestinal tract targeted delivery with a multiphasic release pattern and with good stability and uniformity. However, the release of PB from the microcapsules was not controlled, suggesting uneven distribution of the drug within the microcapsules.

Alginate Particles as Platform for Drug Delivery by the Oral Route: State-of-the-Art

Pharmaceutical research and development aims to design products with ensured safety, quality, and efficacy to treat disease. To make the process more rational, coherent, efficient, and cost-effective, the field of Pharmaceutical Materials Science has emerged as the systematic study of the physicochemical properties and behavior of materials of pharmaceutical interest in relation to product performance. The oral route is the most patient preferred for drug administration. The presence of a mucus layer that covers the entire gastrointestinal tract has been exploited to expand the use of the oral route by developing a mucoadhesive drug delivery system that showed a prolonged residence time. Alginic acid and sodium and potassium alginates have emerged as one of the most extensively explored mucoadhesive biomaterials owing to very good cytocompatibility and biocompatibility, biodegradation, sol-gel transition properties, and chemical versatility that make possible further modifications to tailor their properties. The present review overviews the most relevant applications of alginate microparticles and nanoparticles for drug administration by the oral route and discusses the perspectives of this biomaterial in the future.