Formulation of ciprofloxacin hydrochloride loaded biodegradable nanoparticles: optimization of technique and process variables

Poly lactic-co-glycolic acid (PLGA 502 H) nanoparticles incorporating ciprofloxacin HCl (CP) were prepared by double emulsion solvent diffusion technique.Methods: The influence of the application of probe sonication besides the high pressure homogenization in the preparation of the secondary emulsion and its application during the solidification step were studied. Their effect on the particle size, Zeta potential and the percent encapsulation efficiency of the drug (EE %) were investigated. The effect of the addition of polyvinyl alcohol (PVA) during the preparation of the primary emulsion was studied. Moreover, the effect of the addition of 0.1 M sodium chloride and/or adjusting the external and extracting phases to pH 7.4 were investigated. The selected formula was examined using IR, X-ray, DSC and SEM and in vitro drug release.Results: These formulations showed an appropriate particle size ranges between 135.7– 187.85 nm, a mean zeta potential ranging from 0.839 to 6.81 mV and a mean EE% which ranged from 35% to 69%.Conclusion: The presented data revealed the superiority of using probe sonication besides high pressure homogenization during the formation of secondary emulsion. Moreover, the results indicated that the tested factors had a pronounced significant effect on the EE%

Improving tadalafil dissolution via surfactant-enriched tablets approach: Statistical optimization, characterization, and pharmacokinetic assessment

Tadalafil suffers from poor aqueous solubility that could lead to fluctuating blood levels and unreproducible effect. Thus, this work aimed at improving tadalafil dissolution utilizing the approach of surfactant-enriched tablets. The feasibility of minimizing various surfactants quantities was investigated by establishing the ratio of the surfactant to drug that is required for drug solubilization in micellar solutions. Based on the computed ratios, Tween was precluded from formulation studies due to its poor solubilizing capacity towards the drug. 23 factorial design was employed to assess the impact of formulation attributes on tablets' characteristics. Based on the statistical analysis and the desirability function approach, tablet formulation F6 prepared using CTAB, Avicel PH 102, and 5% Ac-Di-Sol was selected as the optimum formulation. The selected formulation showed adequate stability after storage at 40 C and 75% R.H. for twelve weeks. Pharmacokinetic study revealed that the selected surfactantenriched tablet formulation F6 showed enhanced bioavailability compared to the market product Cialis®

Anti-inflammatory sunscreen nanostructured lipid carrier formulations

Discoid lupus erythematosus is a condition of chronic inflammation of the skin which requires protection from ultraviolet radiations and prolonged treatment with topical corticosteroids. The aim of this study was to prepare semisolid nanostructured lipid carrier (NLC) formulations containing diflucortolone valerate (DFV) as a model corticosteroid drug and titanium dioxide (TiO2) as an inorganic UV-filter in the same formulation. The NLC formulations were prepared by applying high shear homogenization and ultrasonication techniques using Precriol®ATO5 or Tristearin® as the solid lipids, Capryol™ or isopropyl myristate as the liquid lipids, Poloxamer® 407 as a surfactant and Labrafil ® M1944CS as a lipid based surfactant. The incorporation of TiO2 in the NLCs in concentration of 5% w/w was found to be the optimum concentration which enhances the intrinsic sun protection factor (SPF) of this carrier system and resulted in suitable sun protection values ranged from 4.94 to 21.27 with an acceptable spreadable consistency for the NLC formulation. Semi-solid NLC formulations were characterized by small particle size ranged from 180.8 to 255.1 nm before the addition of TiO2 and the particle size reached 540.1 nm after addition of 5% TiO2. Incorporation of TiO2 in NLC formulations leads to a synergistic photoprotection and increase patient compliance

Nanostructured Lipid Carriers as Semisolid Topical Delivery Formulations for Diflucortolone Valerate

Context: Topical treatment of skin disease needs to be strategic to ensure high drug concentration in the skin with minimum systemic absorption. Objective: The aim of this study was to produce semisolid nanostructured lipid carrier (NLC) formulations, for topical delivery of the corticosteroid drug, diflucortolone valerate (DFV), with minimum systemic absorption. Method: NLC formulations were developed using a high shear homogenization combined with sonication, using Precirol ATO5 or Tristearin as the solid lipid, Capryol or isopropyl myristate as the liquid lipid and Poloxamer 407 as surfactant. The present study addresses the influence of different formulations composition as solid lipid, liquid lipid types and concentrations on the physicochemical properties and drug release profile from NLCs. Results and discussion: DFV-loaded NLC formulations possessed average particle size ranging from 160.40 nm to 743.7 nm with narrow polydispersity index. The encapsulation efficiency was improved by adding the lipid-based surfactants (Labrasol and Labrafil M1944CS) to reach 68%. The drug release from the investigated NLC formulations showed a prolonged release up to 12 h. The dermatopharmacokinetic study revealed an improvement in drug deposition in the skin with the optimized DFV-loaded NLC formulation, in contrast to a commercial formulation. Conclusion: NLC provides a promising nanocarrier system that work as reservoir for targeting topical delivery of DFV

Diflucortolone valerate loaded solid lipid nanoparticles as a semisolid topical delivery system

AbstractSolid lipid nanoparticles (SLNs) are promising delivery carriers that have been utilized for formulation and delivery of various drugs. For topical administration, they are usually incorporated into gel or cream to increase their residence time, which is time-consuming process and could affect their stability and characteristics. Preparation of solid lipid nanoparticles based semisolid formulations could have potential pharmaceutical applications. The aim of this study was to formulate the corticosteroidal drug, diflucortolone valerate (DFV) into topical semisolid SLN formulations using a rapid cheap one-step process. SLN formulations were developed using a high-shear homogenization combined with sonication, using different types of solid lipids (e.g., Geleol®, Precirol® ATO5, Tristearin® and Compritol® 888ATO) and Poloxamer® 407 as a surfactant. Selection of the lipids and using high lipid concentration were the key elements to get semisolid formulation immediately after sonication without incorporating the nanoparticles into a gel or a cream base.DFV SLN formulations possessed average particle size ranging from 203.71±5.61 to 1421.00±16.32nm with a narrow size distribution and possessed shear thinning behavior. Incorporation of lipid based surfactants (Labrasol® or Labrafil®) was found to significantly increase DFV encapsulation efficiency (up to 45.79±4.40%).Semisolid DFV-loaded SLN with high drug encapsulation efficiency and acceptable rheological behavior for topical preparation could be prepared in a one-step process

Nanoparticles as tool for enhanced ophthalmic delivery of vancomycin: a multidistrict-based microbiological study, solid lipid nanoparticles formulation and evaluation

Context: A microbiological multidistrict-based survey from different Egyptian governorates was conducted to determine the most prevalent causative agents of ocular infections in the Egyptian population. Antibiotic sensitivity testing was then performed to identify the most potent antimicrobial agent. Vancomycin (VCM) proved the highest activity against gram-positive Staphylococcus bacteria, which are the most commonly isolated causative agents of ocular infection. However, topically applied VCM suffers from poor ocular bioavailability because of its high molecular weight and hydrophilicity. Objective: the aim of the present study was to develop VCM-loaded solid lipid nanoparticles (SLNs) using water-in-oil-in-water (W/O/W) double emulsion, solvent evaporation technique to enhance ocular penetration and prolong ophthalmic residence of VCM. Method: Two consecutive full factorial designs (24 followed by 32 ) were adopted to study the effect of different formulation and process parameters on SLN formulation. The lipid type and structure, polyvinyl alcohol (PVA) molecular weight and concentration, sonication time, as well as lipid:drug ratio were studied as independent variables. The formulated SLN formulae were evaluated for encapsulation efficiency, particle size, and zeta potential as dependent variables. Results: The statistically-optimized SLN formula (1:1 ratio of glyceryltripalmitate:vancomycin with 1% low molecular weight PVA and 1 min sonication time) had average particle size of 277.25 nm, zeta potential of -20.45, and 19.99% drug encapsulation. Scanning and transmission electron micrographs showed well-defined, spherical, homogenously distributed particles. Conclusion: The present study suggests that VCM incorporation into SLNs is successfully achievable; however, further studies with different nanoencapsulation materials and techniques would be valuable for improving VCM encapsulation

Studying the influence of formulation and process variables on Vancomycin-loaded polymeric nanoparticles as potential carrier for enhanced ophthalmic delivery

Ocular topically applied Vancomycin (VCM) suffers poor bioavailability due to its high molecular weight and hydrophilicity. In the Present investigation, VCM-loaded polymeric nanoparticles (PNPs) were developed aiming to enhance its ocular bioavailability through prolonging its release pattern and ophthalmic residence. PNPs were prepared utilizing double emulsion (W/O/O), solvent evaporation technique. 2 3X4 1 full factorial design was applied to evaluate individual and combined influences of polymer type, Eudragit® RS100, sonication time, and Span® 80 concentration on PNPs particle size, encapsulation efficiency, and zeta potential. Further, the optimized formulae were incorporated in 1% Carbopol® - based gel. In-vivo evaluation of the optimized formulae was performed via Draize test followed by microbiological susceptibility testing on albino rabbits. Results revealed successful formulation of VCM- loaded PNPs was achieved with particle sizes reaching 155 nm and up to 88% encapsulation. Draize test confirmed the optimized formulae as non-irritating and safe for ophthalmic administration. Microbiological susceptibility testing confirmed prolonged residence, higher Cmax. with more than two folds increment in the AUC(0.25- 24) of VCM-PNPs over control groups. Thus, VCMloaded PNPs represent promising carriers with superior achievements for enhanced Vancomycin ophthalmic delivery over the traditional use of commercially available VCM parenteral powder after constitution into a solution by the ophthalmologists