In vitro release study of verapamil hydrochloride through sodium alginate interpenetrating monolithic membranes

Surface engineering of silica based materials with Ni-Fe layered double hydroxide for the efficient removal of methyl orange: Isotherms, kinetics, mechanism and high selectivity studies

Herein, low-cost diatomite (DE) and bentonite (BE) materials were surface modified with Ni-Fe layered double hydroxide (LDHs) (represented as NFD and NFB respectively), using a simple co-precipitation procedure for the removal of methyl orange (MO) dye from water. The adsorbents of both before and after MO adsorption have been studied by XRD, N₂ adsorption-desorption isotherm, FTIR, FESEM-EDX and XPS characterization. The zeta potential analysis was used to observe the surface charge of adsorbents within the pH ranges of 4-10. The MO removal efficiency was significantly improved after LDHs modification, showing a 94.7% and 92.6% efficiency for NFD and NFB at pH 6, respectively. Whereas bare DE and BE have shown removal efficiency of 15.5% and 4.9% respectively. The maximum adsorption capacities of NFD and NFB using the Langmuir isotherm model were found to be 246.9 mgg^-1 and 215.9 mgg^-1 respectively. The designed NFD showed high selectivity towards anionic-based dyes from water and also the effect of salts shows the dye removal percentage was increased and decreased for the addition of Na₂SO₄ and NaCl, respectively. The reusability of NFD and NFB have been studied for a maximum of five cycles and they can remove MO up to four cycles. Therefore, the designed adsorbents can be very effective towards the removal of MO from water and they may be useful for dye-based wastewater treatment.

Functionalized Porous Hydroxyapatite Scaffolds for Tissue Engineering Applications: A Focused Review

Biomaterials have been widely used in tissue engineering applications at an increasing rate in recent years. The increased clinical demand for safe scaffolds, as well as the diversity and availability of biomaterials, has sparked rapid interest in fabricating diverse scaffolds to make significant progress in tissue engineering. Hydroxyapatite (HAP) has drawn substantial attention in recent years owing to its excellent physical, chemical, and biological properties and facile adaptable surface functionalization with other innumerable essential materials. This focused review spotlights a brief introduction on HAP, scope, a historical outline, basic structural features/properties, various synthetic strategies, and their scientific applications concentrating on functionalized HAP in the diverse area of tissue engineering fields such as bone, skin, periodontal, bone tissue fixation, cartilage, blood vessel, liver, tendon/ligament, and corneal are emphasized. Besides clinical translation aspects, the future challenges and prospects of HAP based biomaterials involved in tissue engineering are also discussed. Furthermore, it is expected that researchers may find this review expedient in gaining an overall understanding of the latest advancement of HAP based biomaterials.

Xerogel modified diatomaceous earth microparticles for controlled drug release studies

An alternative facile approach for the surface modification of naturally available diatoms with xerogel for controlled drug release applications.

Preparation of Polysaccharide-Based Microspheres by a Water-in-Oil Emulsion Solvent Diffusion Method for Drug Carriers

Polysaccharide-based microspheres of chitosan, starch, and alginate were prepared by the water-in-oil emulsion solvent diffusion method for use as drug carriers. Blue dextran was used as a water-soluble biomacromolecular drug model. Scanning electron microscopy showed sizes of the resultant microspheres that were approximately 100 μm or less. They were spherical in shape with a rough surface and good dispersibility. Microsphere matrices were shown as a sponge. Drug loading efficiencies of all the microspheres were higher than 80%, which suggested that this method has potential to prepare polysaccharide-based microspheres containing a biomacromolecular drug model for drug delivery applications.

Formulation and evaluation of ciprofloxacin hydrochloride soluble ocular drug insert

PURPOSE

An attempt has been made in the present research to formulate soluble ocular inserts of ciprofloxacin hydrochloride to increase residence time and prolong drug release.

MATERIAL AND METHODS

Drug matrices were prepared using natural polymer. Gelatin, a biodegradable polymer, was tried for the first time in the preparation of soluble ocular drug insert matrices. The inserts were then evaluated for their physicochemical parameters. The in vitro drug release studies were carried out using a bi-chambered donor receiver compartment model. In vivo drug release was carried out using rabbits as animal models.

RESULTS

Formulations CF4 and CF8, which showed controlled and prolonged in vitro drug release, were subjected to in vivo study. In vitro and in vivo correlation was found to be strong, revealing the efficacy of the formulation.

CONCLUSION

Formulation CF8 was found promising, as it achieved the target of the present study.

Swelling studies and in vitro release of verapamil from calcium alginate and calcium alginate–chitosan beads

The aim of the present work was to investigate the swelling behavior and the in vitro release of the antihypertensive drug verapamil hydrochloride from calcium alginate and chitosan treated calcium alginate beads. Calcium-alginate beads, chitosan-coated alginate beads and alginate-chitosan mixed beads were synthesized and their morphology was investigated by scanning electron microscopy. The swelling ability of the beads in different media was found to be dependent on the presence of the polyelectrolyte complex between alginate and chitosan, the pH of the aqueous media and the initial physical state of the beads. The results revealed that the encapsulation of verapamil in both calcium-alginate and calcium alginate-chitosan mixed beads exceeded 80%. Considering the in vitro stability of verapamil encapsulating beads, 70% of the drug released from wet and dry plain calcium alginate beads within 1 and 3h, respectively. The presence of chitosan was found to retard significantly the release from wet beads. However, in the case of dry beads the presence of chitosan had no significant effect on the initial release stage and significantly increased the release on the later stage. The results were analyzed by using a semi-empirical equation and it was found that the drug release mechanisms were either "anomalous transport" or "case-II transport".

Anti-microbial activity and film characterization of thiazolidinone derivatives of chitosan

Thiazolidinone derivatives (TDCs) were prepared by converting chitosan into chitosan's Schiff's bases (CSBs), followed by treatment with mercaptoacetic acid. Both CSBs and TDCs were tested for antimicrobial activity against four different bacteria. All TDCs showed comparatively better anti-microbial activity without much affecting basic physical properties of chitosan such as film-forming capacity, tensile strength, etc. This indicates that chitosan derivatives with a thiazolidinone moiety might be a better material for wound dressing.