Supramolecular curcumin-barium prodrugs for formulating with ceramic particles.

A simple and stable curcumin-ceramic combined formulation was developed with an aim to improve curcumin stability and release profile in the presence of reactive ceramic particles for potential dental and orthopedic applications. For that, curcumin was complexed with barium (Ba(2+)) to prepare curcumin-barium (BaCur) complex. Upon removal of the unbound curcumin and Ba(2+) by dialysis, a water-soluble BaCur complex was obtained. The complex was showing [M+1](+) peak at 10,000-20,000 with multiple fractionation peaks of MALDI-TOF-MS studies, showed that the complex was a supramolecular multimer. The (1)H NMR and FTIR studies revealed that, divalent Ba(2+) interacted predominantly through di-phenolic groups of curcumin to form an end-to-end complex resulted in supramolecular multimer. The overall crystallinity of the BaCur was lower than curcumin as per XRD analysis. The complexation of Ba(2+) to curcumin did not degrade curcumin as per HPLC studies. The fluorescence spectrum was blue shifted upon Ba(2+) complexation with curcumin. Monodisperse nanoparticles with size less than 200dnm was formed, out of the supramolecular complex upon dialysis, as per DLS, and upon loading into pluronic micelles the size was remaining in similar order of magnitude as per DLS and AFM studies. Stability of the curcumin was improved greater than 50% after complexation with Ba(2+) as per UV/Vis spectroscopy. Loading of the supramloecular nanoparticles into pluronic micelles had further improved the stability of curcumin to approx. 70% in water. These BaCur supramolecule nanoparticles can be considered as a new class of prodrugs with improved solubility and stability. Subsequently, ceramic nanoparticles with varying chemical composition were prepared for changing the material surface reactivity in terms of the increase in, degradability, surface pH and protein adsorption. Further, these ceramic particles were combined with curcumin prodrug formulations and optimized the curcumin release properties in the combined formulations. Our proof concept study shows that, the conversion of curcumin to a metal-organic supramolecular prodrug improved the solubility, stability and release profile of curcumin. The prodrug approach with the micellisation strategy appears to be more appropriate to deliver intact curcumin in the presence of ceramic particles of varying surface reactivity.

Anti-inflammatory activity of Premna corymbosa (Burm.f.) Rottl. & Willd. leaves extracts in Wistar albino rats.

OBJECTIVE: To evaluate the acute toxicity and to investigate the effect of Premna corymbosa ethanolic extract (PCEE) at doses of 200 and 400 mg/kg body weight in acute and chronic models of inflammation in experimental animals. METHODS: In the acute toxicity study, a single dose of PCEE of 2 000 mg/kg body weight, p.o. was administered and observed for 48 h. In acute models as egg albumin induced paw edema and chronic model as cotton pellet methods was followed. RESULTS: In acute models, egg albumin induced paw edema PCEE significantly (P<0.01) inhibited the edema formation. In chronic model, cotton pellet induced granuloma formation in rats PCEE significantly (P<0.01) reduced the granuloma formation with percentage inhibition of 35.17% and 50.38 % respectively. CONCLUSIONS: The present study establishes the antiinflammatory activity of Premna corymbosa leaves.