Preparation and Optimization of Immediate Release/Sustained Release Bilayered Tablets of Loxoprofen Using Box-Behnken Design.

The aim of our current study was to characterize and optimize loxoprofen immediate release (IR)/sustained release (SR) tablet utilizing a three-factor, three-level Box-Behnken design (BBD) combined with a desirability function. The independent factors included ratio of drug in the IR layer to total drug (X 1), ratio of HPMC to drug in the SR layer (X 2), and ratio of Eudragit RL PO to drug in the SR layer (X 3). The dependent variables assessed were % drug released in distilled water at 30 min (Y 1), % drug released in pH 1.2 at 2 h (Y 2), and % drug released in pH 6.8 at 12 h (Y 3). The responses were fitted to suitable models and statistical validation was performed using analysis of variance. In addition, response surface graphs and contour plots were constructed to determine the effects of different factor level combinations on the responses. The optimized loxoprofen IR/SR tablets were successfully prepared with the determined amounts of ingredients that showed close agreement in the predicted and experimental values of tablet characterization and drug dissolution profile. Therefore, BBD can be utilized for successful optimization of loxoprofen IR/SR tablet, which can be regarded as a suitable substitute for the current marketed formulations.

Preparation and characterization of fast dissolving flurbiprofen and esomeprazole solid dispersion using spray drying technique.

We aimed to develop an immediate-release flurbiprofen (FLU) and esomeprazole (ESO) combination formulation with enhanced gastric aqueous solubility and dissolution rate. Aqueous solubility can be enhanced by formulating solid dispersions (SDs) with a polyvinylpyrrolidone (PVP)-K30 hydrophilic carrier, using spray-drying technique. Aqueous and gastric pH dissolution can be achieved by macro-environmental pH modulation using sodium bicarbonate (NaHCO3) and magnesium hydroxide (Mg(OH)2) as the alkaline buffer. FLU/ESO-loaded SDs (FLU/ESO-SDs) significantly improved aqueous solubility of both drugs, compared to each drug powder. Dissolution studies in gastric pH and water were compared with the microenvironmental pH modulated formulations. The optimized FLU/ESO-SD powder formulation consisted of FLU/ESO/PVP-K30/sodium carbonate (Na2CO3) in a weight ratio 1:0.22:1.5:0.3, filled in the inner capsule. The outer capsule consisted of NaHCO3 and Mg(OH)2, which created the macro-environmental pH modulation. Increased aqueous and gastric pH dissolution of FLU and ESO from the SD was attributed to the alkaline buffer effects and most importantly, to drug transformation from crystalline to amorphous SD powder, clearly revealed by scanning electron microscopy, differential scanning calorimetry, and powder X-ray diffraction studies. Thus, the combined FLU and ESO SD powder can be effectively delivered as an immediate-release formulation using the macro-environmental pH modulation concept.

PEGylated lipid bilayer-supported mesoporous silica nanoparticle composite for synergistic co-delivery of axitinib and celastrol in multi-targeted cancer therapy.

UNLABELLED: Small-molecule drug combination therapies are an attractive approach to enhancing cancer chemotherapeutic responses. Therefore, this study aimed to investigate the potential of axitinib (AXT) and celastrol (CST) in targeting angiogenesis and mitochondrial-based apoptosis in cancer. Therefore, we prepared AXT/CST-loaded combination nanoparticles (ACML) with CST loaded in the mesoporous silica nanoparticles (MSN) and AXT in PEGylated lipidic bilayers. We showed that ACML effectively inhibited angiogenesis and mitochondrial function and was efficiently internalized in SCC-7, BT-474, and SH-SY5Y cells. Furthermore, hypoxia-inducible factor (HIF)-1α expression, which increased under hypoxic conditions in all cell lines exposed to ACML, markedly decreased, which may be critical for tumor inhibition. Western blotting showed the superior anticancer effect of combination nanoparticles in different cancer cells. Compared to the cocktail (AXT/CST), ACML induced synergistic cancer cell apoptosis. The AXT/CST-based combination nanoparticle synergism might be mediated by AXT, which controls vascular endothelial growth factor receptors while CST acts on target cell mitochondria. Importantly, ACML-treated mice showed remarkably higher tumor inhibition (64%) than other groups did in tumor xenograft models. Tumor xenograft immunohistochemistry revealed elevated caspase-3 and poly (ADP-ribose) polymerase and reduced CD31 and Ki-67 expression, clearly suggesting tumor apoptosis through mitochondrial and antiangiogenic effects. Overall, our results indicate that ACML potentially inhibited cell proliferation and induced apoptosis by blocking mitochondrial function, leading to enhanced antitumor efficacy. STATEMENT OF SIGNIFICANCE: In this research, we formulated an anticancer drug combination nanoparticle loaded with axitinib (AXT) in the lipidic bilayer of PEGylated liposomes and celastrol (CST) in mesoporous silica nanoparticles. The anticancer effects of the AXT/CST-loaded combination nanoparticle (ACML) were synergistic and superior to the other formulations and involved more efficient drug delivery to the tumor site with enhanced effects on angiogenesis and mitochondrial function. Therefore, our study demonstrated that the inhibition of cell proliferation and induction of apoptosis by ACML, which was mediated by blockade of mitochondrial function and anti-angiogenesis, led to enhanced antitumor efficacy, which may be potentially useful in the clinical treatment of cancer.