Fabrication and evaluation of fast disintegrating pellets of cilostazol.

The present study was designed to formulate and develop fast disintegrating pellets of poorly soluble model drug (cilostazol) by reducing the proportion of micro-crystalline cellulose with pre-gelatinized starch (PGS), lactose and chitosan. The bioavailability enhancement of a model drug was achieved by preparing inclusion complex with Captisol® (Sulfobutyl Ether ß cyclodextrin - SBE-ß-CD). Extrusion-spheronization technique was used to formulate pellets. Placket-Burman design was used for the initial screening of most significant factors such as screen size (mm), ratio of micro crystalline cellulose: PGS + lactose + chitosan and % of HPMC which affects pellet properties. The inclusion complex of drug and Captisol® (SBE-ß-CD) was prepared by Solvent Evaporation method and were incorporated into pellets in a predefined proportion. Formulation was optimized by using 32 full factorial design, the optimized batch was selected on the basis of dependent variables such as % yield, pellet size, disintegration time and % Cumulative drug release (%CDR), the obtained results were 87.15%, 0.75 mm, 13 min and 91.024% respectively. Differential scanning calorimetry (DSC) and Fourier transform infrared spectrometry (FTIR) study revealed no significant interaction between drug and polymer. Scanning electron microscopy (SEM) confirmed uniform and spherical shaped pellets having pores on the surface which facilitates wicking action and fast disintegrating property of pellets. A design space was constructed to meet the desirable target and optimized batch. The scope of study can further extended to hydrophobic molecules which may useful due to rapid disintegration and enhanced dissolution rate.

Formulation and development of ophthalmic in situ gel for the treatment ocular inflammation and infection using application of quality by design concept.

CONTEXT: The conventional liquid ophthalmic delivery systems exhibit short pre-corneal residence time and the relative impermeability to the cornea which leads to poor ocular bioavailability. OBJECTIVE: The aim of this study was to apply quality by design (QbD) for development of dexamethasone sodium phosphate (DSP) and tobramycin sulfate (TS)-loaded thermoresponsive ophthalmic in situ gel containing Poloxamer 407 and hydroxyl propyl methyl cellulose (HPMC) K4M for prolonging the pre-corneal residence time, ocular bioavability and decreases the frequency of administration of dosage form. The material attributes and the critical quality attributes (CQA) of the in situ gel were identified. Central composite design (CCD) was adopted to optimize the formulation. MATERIALS AND METHODS: The ophthalmic in situ forming gels were prepared by cold method. Materials attributes were the amount of Poloxamer 407 and HPMC and CQA identified were Gel strength, mucoadhesive index, gelation temperature and % of drug release of both drug. RESULTS AND DISCUSSION: Optimized batch (F*) containing 16.75% poloxamer 407 and 0.54% HPMC K4M were exhibited all results in acceptable limits. Compared with the marketed formulation, optimized in situ gel showed delayed Tmax, improved Cmax and AUC in rabbit aqueous humor, suggesting the sustained drug release and better corneal penetration and absorption. CONCLUSION: According to the study, it could be concluded that DSP and TS would be successfully formulated as in situ gelling mucoadhesive system for the treatment of steroid responsive eye infections with the properties of sustained drug release, prolonged ocular retention and improved corneal penetration.

Identification of novel protein kinase C-ßII inhibitors: virtual screening, molecular docking and molecular dynamics simulation studies.

Diabetic wounds (DWs) are the major end-stage manifestation encountered in diabetic patients. The two major pathways involved in the pathogenesis of DW are impaired angiogenesis and unnecessary NETosis, which are regulated by a common enzyme called protein kinase C (PKC)-ßII. PKC-ßII is a conventional isoform of PKC family that can be activated by calcium and diacylglycerol. PKC-ßII possesses a specific expression profile and plays a distinct role in various cellular and molecular functions. The pathogenic role of PKC-ßII and its involvement in the impairment of wound healing suggested that PKC-ßII plays a potential role in DW progression. Hence, there is a renewed interest in developing specific inhibitors of PKC-ßII. In the present study, receptor-based virtual screening was performed for the identification of potential PKC-ßII inhibitors using TimTec, Enamine, Zinc and Specs databases. A total of 595 candidate compounds were evaluated based on absorption, distribution, metabolism, excretion and toxicity, standard precision docking. Further, extra-precision docking and binding free energy calculations were carried out for top-ranked compounds. Based on Glide score and protein-ligand interactions, we have identified compound 1 as a potential inhibitor. Finally, molecular dynamics (MD) simulation was performed for top compound 1 using the Desmond module (Schrödinger suite) to identify the structural stability of the protein-ligand complex. Gratifyingly, MD trajectory analysis demonstrated the stable binding conformation of compound 1 with PKC-ßII enzyme. In silico approaches incorporated in this study provide a set of new putative PKC-ßII inhibitors which could be potential leads to develop DW therapeutics.

Screening of Sacrificial Excipients for Arresting Devitrification of Itraconazole from Solid Dispersion.

OBJECTIVES: The aim of the present investigation was to develop a solid dispersion of itraconazole (ITR) using sacrificial excipients like pregelatinized starch and spray-dried lactose alongside hydroxypropyl methylcellulose and Poloxamer 188, thereby arresting the conversion of the amorphous form of ITR to crystalline form, and to assess the dissolution stability of an amorphous form of the drug during short-term storage. MATERIALS AND METHODS: ITR-loaded solid dispersions were prepared by kneading. Formulation optimization was achieved by using a 24 full factorial design on the basis of cumulative percent drug released at t30, t60, and t120 min. An artificial neural network (ANN) was also applied as a statistical tool for obtaining better predictive ability and the outcomes of the ANN were compared with that of Design-Expert software. RESULTS: The spectral data revealed no drug-carrier interactions. The P-X-ray diffraction study of the optimized batch showed a decrease in the crystallinity of drug as compared to the untreated drug. The in vitro dissolution studies of the optimized batch showed higher dissolution (92% at 120 min) in comparison to the other formulations. The dissolution stability study was performed at 40°C and 75% relative humidity for 90 days for the optimized formulation. The results of the optimized batch showed insignificant changes in cumulative percentage drug release during storage. CONCLUSION: Dissolution stability could be attributed to the presence of sacrificial excipients as they tend to absorb moisture during storage and possibly get converted into crystalline form, thereby minimizing the recrystallization of ITR.

Development of Biodegradable Injectable In situ Forming Implants for Sustained Release of Lornoxicam.

OBJECTIVE: The focus of this study was to develop in situ injectable implants of Lornoxicam which could provide sustained drug release. METHODS: Biodegradable in situ injectable implants were prepared by polymer precipitation method using polylactide-co-glycolide (PLGA). An optimized formulation was obtained on the basis of drug entrapment efficiency, gelling behavior and in vitro drug release. The compatibility of the formulation ingredients were tested by Fourier transform infrared (FT-IR) spectroscopy, and differential scanning colorimetry (DSC). SEM study was performed to characterize in vivo behavior of in situ implant. Pharmacokinetic study and in vivo gelling study of the optimized formulation were performed on Sprague-Dawley rats. Stability testing of optimized formulation was also performed. RESULTS: The drug entrapment efficiency increased and burst release decreased with an increase in the polymer concentration. Sustained drug release was obtained up to five days. SEM photomicrographs indicated uniform gel formation. Chemical interaction between the components of the formulation was not observed by FT-IR and DSC study. Pharmacokinetic studies of the optimized formulation revealed that the maximum plasma concentration (Cmax), time to achieve Cmax (Tmax) and area under plasma concentration curve (AUC) were significantly higher than the marketed intramuscular injection of lornoxicam. Stability study of optimized batch showed no change in physical and chemical characteristics. CONCLUSION: Lornoxicam can be successfully formulated as in situ injectable implant that provides long-term management of inflammatory disorders with improved patient compliance.

Development and Optimization of Dispersible Tablet of Bacopa monnieri with Improved Functionality for Memory Enhancement.

INTRODUCTION: The Bacopa monnieri is traditional Ayurvedic medicine, and reported for memory-enhancing effects. The Bacoside is poorly soluble, bitter in taste and responsible for the memory enhancement action. Memory enhancer is commonly prescribed for children or elder people. OBJECTIVE: Poor solubility, patient compliance and bitterness were a major driving force to develop taste masked ß-cyclodextrin complex and dispersible tablets. MATERIALS AND METHODS: The inclusion complex of Bacopa monnieri and ß-cyclodextrin was prepared in different molar ratios of Bacopa monnieri by Co-precipitation method. Phase solubility study was conducted to evaluate the effect of ß-cyclodextrin on aqueous solubility of Bacoside A. The characterization was determined by Fourier transformation infrared spectroscopy (FTIR),Differential scanning calorimetry (DSC) and X-ray diffraction study (XRD).Crospovidone and croscarmallose sodium were used as super disintigrant. The 32 full factorial design was adopted to investigate the influence of two superdisintegrants on the wetting time and disntegration time of the tablets. CONCLUSION: The result revels that molar ratio (1:4) of inclusion complex enhance 3-fold solubility. Full factorial design was successfully employed for the optimization of dispersible tablet of B. monnieri. The short-term accelerated stability study confirmed that high stability of B. monnieri in inclusion complex.

Development and characterization of novel hydrogel containing antimicrobial drug for treatment of burns.

INTRODUCTION: The aim of burn management and therapy is fast healing and epithelisation to prevent infection. The present study is concerned with the development and characterization of a novel nanaoparticulate system; cubosomes, loaded with silver sulfadiazine (SSD) and Aloe vera for topical treatment of infected burns. METHODS: Cubosome dispersions were formulated by an emulsification technique using different concentrations of a lipid phase Glyceryl Monooleate (GMO) and Poloxamer 407. The optimum formulae were incorporated in an aloe vera gel containing carbopol 934, to form cubosomal hydrogels (cubogels). The cubogels were characterized by in vitro release of SSD, rheological properties, pH, bioadhesion, Transmission Electron Microscopy and in-vivo Wound Healing Study. RESULTS: The results show that the different concentration of GMO had significant effect on particle size, % EE and in vitro drug release. From the in-vitro drug release pattern and similarity factor (f2), it was concluded that batch CG3 (15% GMO and 1% P407) exhibited complete and controlled drug release within 12 hour (i.e. 98.25%), better bio adhesion and superior burn healing as compared to the marketed product. CONCLUSION: The in vivo burns healing study in rats revealed that the prepared optimized cubogel containing SSD and aloe vera has superior burns healing rate than cubogel with only SSD and marketed preparation so, it may be successfully used in the treatment of deep second degree burn.