ABSTRACT
An attempt was made to formulate nebivolol-loaded microsponge gel to access drug at wound area, incorporated into gel that possess optimum moist wound management environment during later stages of wound closure. Nebivolol, antihypertensive drug, exhibits vasodilating effects via nitric oxide pathway, slows diabetic neuropathy, and restores endothelial function in diabetic wounds. Microsponges were prepared by optimizing independent variables; drug to polymer ratio and internal phase volume and their effects on production yield, entrapment efficiency, and particle size. Formulations of microsponges were evaluated for drug content. Differential scanning calorimetry indicated reduction in crystallinity of NB during the formation of microsponges. In vitro study (drug to polymer 1:4 and 10 ml internal phase volume acetone) showed 80% drug released within 8 h. Spherical and porous microsponges confirmed by scanning electron microscopy were incorporated in the carbopol 934 (2%) gel base. Gel was characterized for pH, viscosity, and drug content. Less spreadability determined by texture analyzer demonstrated viscous nature of gel. In vitro diffusion study revealed entrapped drug in porous microsponges with slow release to heal wound. In vivo study performed using streptozotocin-induced diabetic rats and excision wound model showed wound healing and closure activity within day 10. Histology revealed inflammatory cell infiltrations and neovascularization in granulation tissues, ultimately healing wound. Microsponge gel prolonged drug release due to entrapped form in porous structure of microsponges with significant and fast wound healing and closure in diabetic rats. Microsponges with loaded drug fulfilled accessibility at wound area, while gel provided optimum moist wound management environment during later stages of wound closure.
Subject(s)
Diabetes Complications/drug therapy , Diabetes Mellitus, Experimental/complications , Gels/administration & dosage , Gels/chemistry , Nebivolol/administration & dosage , Nebivolol/chemistry , Wound Healing/drug effects , Animals , Chemistry, Pharmaceutical/methods , Drug Delivery Systems/methods , Drug Liberation , Particle Size , Polymers/chemistry , Porosity , Rats , Rats, Sprague-DawleyABSTRACT
The present study was aimed at formulating thermoreversible in situ gel of local anesthetic by using xyloglucan based mucoadhesive tamarind seed polysaccharide (TSP) into periodontal pocket. Temperature-sensitive in situ gel of lidocaine hydrochloride (LH) (2% w/v) was formulated by cold method. A full 3(2) factorial design was employed to study the effect of independent variables concentrations of Lutrol F127 and TSP to optimize in situ gel. The dependent variables evaluated were gelation temperature (Y 1) and drug release (Y 2). The results revealed the surface pH of 6.8, similar to the pH of saliva. Viscosity study showed the marked increase in the viscosity of gel at 37°C due to sol-gel conversion. TSP was found to act as good mucoadhesive component to retain gel at the site of application in dental pocket. Gelation of formulation occurred near to body temperature. In vitro study depicted the fast onset of drug action but lasting the release (90%) till 2 h. Formulation F7 was considered as optimized batch, containing 18% Lutrol F127 and 1% tamarind seed polysaccharide. Thus, lidocaine hydrochloride thermoreversible in situ gel offered an alternative to painful injection therapy of anesthesia during dental surgery, with fast onset of anesthetic action lasting throughout the dental procedure.
