Pharmacokinetics and in vivo distribution of optimized PLGA nanoparticles for pulmonary delivery of levofloxacin.

OBJECTIVES: The aim of this study was to develop and optimize levofloxacin loaded PLGA nanoparticles (LN) for pulmonary delivery employing screening and experimental design and evaluate their in-vitro and in-vivo performance. The objective was to achieve Mass Median Aerodynamic Diameter (MMAD) of LN of less than 5µm, sustain the drug release up to 120 h and a higher AUC/MIC at the site of action. METHODS: LN were prepared by modified emulsion solvent evaporation technique employing high speed homogenization, probe sonication and subsequent lyophilization. KEY FINDINGS: The Pareto chart from Placket Burman screening design revealed that homogenization speed and amount of PLGA were found to be significant (P < 0.05). Further analysis by 3 full-factorial design revealed that F-ratio was found to be far greater than the theoretical value (P < 0.05) for each regression model. CONCLUSION: The optimized formulation with desirability value 0.9612 showed mean particle size of 146 nm, MMAD of 4.40 µm and sustained the drug release up to 120 h in simulated lung fluid. Augmentation in Cmax (1.71-fold), AUC 0-∞ (5.46-fold), Mean Residence Time (6.64-fold) and AUC/MIC (6.21-fold) of LN through pulmonary route was found to significantly higher (P < 0.05) than levofloxacin (p. o.).

Microemulgel of Voriconazole: an Unfathomable Protection to Counter Fungal Contagiousness.

BACKGROUND: Fluconazole and ketoconazole both have poor minimum inhibitory concentration than voriconazole. Voriconazole had serious side effects in oral and intravenous doses. It has poor water solubility. The objective of the study was to prepare and optimize microemulgel of voriconazole for topical delivery. AIM: Formulation, development, and evaluation of voriconazole microemulgel for topical delivery. METHODS: Oil and emulsifi ers selected were on the basis of equilibrium solubility study and emulsification property respectively. The pseudo-ternary plot and constrained simplex lattice design were applied for preparation of microemulsions. Microemulsions were subjected to micelle size, zeta potential, polydispersity index, and in vitro study. They were optimized by Design-Expert® 9.0.3.1 software. Formulation, development, evaluation and optimization of microemulgel were carried out. Microbial assay of an optimized batch of microemulgel was performed. RESULTS: Solubility of voriconazole in Parker Neem® oil was 7.51±0.14 mg/g. Acrysol™K-150: PEG-400 in 4:1 ratio had the highest area for microemulsion. 59.2% Acrysol™K-150, 14.8% PEG-400, 11% Parker Neem® oil, 15% rose water, and 1% voriconazole as an optimized batch of microemulsion was selected for preparation of microemulgel. Carbomer 934P found a good gelling agent in 0-2% w/w concentration. An optimized batch of microemulgel had 0.974 desirability value. An optimized batch of microemulgel and Nizral® cream had 37.32±0.63% and 26.45±0.63% zones of inhibition. CONCLUSION: Topical antifungal treatment was successfully achieved with voriconazole microemulgel.

Development and Characterization of Multifunctional Directly Compressible Co-processed Excipient by Spray Drying Method.

The present investigation was carried out to develop and characterize a multifunctional co-processed excipient for improving the compressibility of poorly compressible drugs. Etodolac was used as a model drug. Microcrystalline cellulose (MCC), lactose monohydrate (lactose), and StarCap 1500 (StarCap) were selected as components of the co-processed excipient. The spray drying method was used for co-processing of excipients. D-optimal mixture design was applied to optimize the proportion of component excipients. Statistical analysis of the D-optimal mixture design revealed that all response variables were significantly affected by the independent variables (p value < 0.05). Optimized composition was obtained from the desirability function. The optimized composition of the co-processed excipient was found to be 30% MCC, 25% lactose, and 45% StarCap. This optimized batch was evaluated for flow properties, compressibility parameters such as Kawakita's and Kuno's equation and Heckel's equation, and dilution potential. Evaluation parameters for flow properties (angle of repose, Carr's index, and Hausner's ratio) suggested excellent flow character. The parameters of Kawakita's and Kuno's equation and Heckel's equation suggested improvement in the compressibility of the model drug. Dilution potential was found to be 40%, and based on that, tablets of the model drug were formulated and evaluated for general evaluation parameters of tablets. All the parameters were found to be within the acceptance criteria which concluded that the multifunctional directly compressible co-processed excipient was prepared successfully that improved the compressibility of the poorly compressible model drug etodolac along with spray drying as an efficient method for the preparation of co-processed excipient.

Self-nanoemulsifying drug delivery system of glimepiride: design, development, and optimization.

The objective of the present investigation was to develop and characterize the self-nanoemulsifying drug delivery system (SNEDDS) of glimepiride, a poorly soluble drug. Solubility of glimepiride in various vehicles was determined, and ternary phase diagrams were constructed using a suitable oil, surfactant, and cosurfactant system to find out the efficient self-emulsification system. A three factor, three level Box-Behnken statistical design was employed to explore the main and interaction effect of independent variables, namely X1 (amount of Capmul MCM), X2 (amount of Acrysol K 140), and X3 (amount of Transcutol P). Percent transmittance value (Y1), droplet diameter (Y2), and percent drug released at 5 min (Y3) were the dependent variables. Formulation optimization was carried out to optimize the droplet diameter and percent drug dissolved at 5 min. The batch prepared according to the optimized formulation showed a close agreement between observed and predicted values. Box-Behnken statistical design allowed us to understand the effect of formulation variables on the rapid dissolution of drug from SNEDDS and to optimize the formulation to obtain a rapid drug dissolution at 5 min. LAY ABSTRACT: A self-nanoemulsifying drug delivery system of glimepiride has been design, developed, and optimized. A three factor, three level Box-Behnken statistical design was employed to explore the main and interaction effect of independent variables, namely X1 (amount of Capmul MCM), X2 (amount of Acrysol K 140), and X3 (amount of Transcutol P). Percent transmittance value (Y1), droplet diameter (Y2), and percent drug released at 5 min (Y3) were the dependent variables. The Capmul MCM-Akcrysol K 140-Transcutol system was found to be the suitable ternary system that was able to release almost 80% of drug within the first 5 min. The improved dissolution of glimepiride might improve patient compliance.

Formulation and evaluation of glipizide floating-bioadhesive tablets

The purpose of this study was formulation and in vitro evaluation of floating-bioadhesive tablets to lengthen the stay of glipizide in its absorption area. Effervescent tablets were made using chitosan (CH), hydroxypropyl methylcellulose (HPMC), carbopolP934 (CP), polymethacrylic acid (PMA), citric acid, and sodium bicarbonate. Tablets with 5 percent effervescent base had longer lag time than 10 percent. The type of polymer had no significant effect on the floating lag time. All tablets floated atop the medium for 23-24 hr. Increasing carbopolP934 caused higher bioadhesion than chitosan (p < 0.05). All formulations showed a Higuchi, non-Fickian release mechanism. Tablets with 10 percent effervescent base, 80 percent CH/20 percent HPMC, or 80 percent CP/20 percent PMA seemed desirable.

Formulation and evaluation of stomach-specific amoxicillin-loaded carbopol-934P mucoadhesive microspheres for anti-Helicobacter pylori therapy.

The purpose of this research was to formulate and systemically evaluate in vitro and in vivo performances of mucoadhesive amoxicillin microspheres for the potential use in the treatment of gastric and duodenal ulcers, which were associated with Helicobacter pylori. Amoxicillin mucoadhesive microspheres containing carbopol-934P as mucoadhesive polymer and ethyl cellulose as carrier polymer were prepared by an emulsion-solvent evaporation technique. Results of preliminary trials indicate that quantity of emulsifying agent, time for stirring, drug-to-polymers ratio and speed of rotation affected the characteristics of microspheres. Microspheres were discrete, spherical, free flowing and showed a good percentage of drug entrapment efficiency. An in vitro mucoadhesive test showed that amoxicillin mucoadhesive microspheres adhered more strongly to the gastric mucous layer and could retain in the gastrointestinal tract for an extended period of time. A 3(2) full factorial design was employed to study the effect of independent variables, drug-to-polymer-to-polymer ratio (amoxicillin-ethyl cellulose-carbopol-934P) (X(1)) and stirring speed (X(2)) on dependent variables, i.e. percentage mucoadhesion, drug entrapment efficiency, particle size and t(80). The best batch exhibited a high drug entrapment efficiency of 56%; mucoadhesion percentage after 1 h was 80% and the particle size was 109 µm. A sustained drug release was obtained for more than 12 h. The drug-to-polymer-to-polymer ratio had a more significant effect on the dependent variables. The morphological characteristics of the mucoadhesive microspheres were studied under a scanning electron microscope. In vitro release test showed that amoxicillin released slightly faster in pH 1.2 hydrochloric acid than in pH 7.8 phosphate buffer. In vivo H. pylori clearance tests were also carried out by administering amoxicillin powder and mucoadhesive microspheres to H. pylori infectious Wistar rats under fed conditions at single dose or multiple dose(s) in oral administration. The results showed that amoxicillin mucoadhesive microspheres had a better clearance effect than amoxicillin powder. In conclusion, the prolonged gastrointestinal residence time and enhanced amoxicillin stability resulting from the mucoadhesive microspheres of amoxicillin might make a contribution to H. pylori complete eradication.