To increase the low bioavailability and short ocular residence time of ciprofloxacin eye drops, aqueous solutions of drug in chitosan/ Pluronic (poloxamer) were prepared to identify suitable compositions with regard to gel forming properties and drug release behavior. Mixtures of solutions of Pluronic (10-25% w/w) with chitosan (0.1-0.3% w/w) of different molecular weights (Mw) were prepared. Ciprofloxacin release was determined using a membraneless dissolution model in artificial tear solution up to 8 hours and the samples were analyzed spectrophotometrically at 272.4nm. The rheological behavior of solutions in response to dilution or temperature changes and also the phase change temperature (PCT) were determined using a Cup & Bob viscometer. Antimicrobial effect of the solutions was studied in nutrient agar in comparison to marketed solutions of ciprofloxacin using Pseudomonas aueroginosa and Staphylococcus aureus by the agar diffusion test using the cup-plate technique. The formulation consisted of 15% Pluronic and 0.1% low Mw chitosan, with the highest release efficiency (46.61 ± 0.41%) and an acceptable mean release time (1.94 ± 0.27 hr), is suggested as a suitable ophthalmic preparation for sustained release of ciprofloxacin. This in situ gel released the drug by a Higuchi model and Fickian mechanism. It was liquid in non-physiologic conditions (pH 4 and 25ºC) and transferred to the gel form upon physiologic conditions (pH 7.4 and 37ºC). The PCT of this in situ gel did not change upon dilution and the zone of inhibition of the growth of both studied bacteria was significantly greater for it than the marketed eye drop of ciprofloxacin.

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Solid lipid nanoparticles (SLNs) of buspirone HCl as a water-soluble drug were prepared by emulsification-evaporation, followed by the sonification method. A preliminary screening of the most effective parameters on the production of nanoparticles by a Taguchi L(8) orthogonal array showed that the lipid type, surfactant percentage, speed of homogenizer, and acetone:dichloromethane (DCM) ratio had a significant effect on particle size. In the next step, the lipid was fixed on cetyl alcohol, surfactant on Tween 20, lecithin:lipid weight ratio on 20:70, sonication time on 30 seconds, and the other effective, independent factors aforementioned were studied each at three levels by a three-factor, three-level Box-Behnken design. The percentage of drug entrapment, mean particle-size diameter, and zeta potential were studied as the responses. Contour plots were constructed to further elucidate the relationship between the independent and dependent variables. A pharmacokinetic study was conducted in male Wistar rats after oral administration of 15 mg.kg(-1) buspirone in the form of free drug or SLNs. The optimized SLNs had aq particle size of 345.7 nm, loading efficiency of 32.8%, and zeta potential of -6.8 mV. Buspirone released about 90% during 4.5 hours in vitro. It was found that the relative bioavailability of the drug in SLNs was significantly increased, compared to that of the drug solution.

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Oral mucositis (OM) represents a therapeutic challenge frequently encountered in cancer patients undergoing chemotherapy or radiotherapy. Erythropoietin (EPO) has anti-inflammatory, antioxidant, and wound-healing properties and therefore has important roles in the prevention and treatment of OM. In the current study, we developed a thermally sensitive mucoadhesive gel based on trimethyl chitosan (TMC) containing EPO for the treatment of OM. TMCs with various degrees of substitution (DS) were synthesized and mixed with β-glycerophosphate (GP) and characterized for gelation properties by means of rheological analysis. The effects of DS of TMCs and different concentrations of GP on gelation temperature and time were investigated. The mucoadhesive property of the mixtures was also assessed using cattle buccal mucosa. The optimized mixture was loaded with EPO and subjected to in vitro drug release, wash away, in vitro antimicrobial, and wound-healing tests. The effect of EPO-loaded formulation was also investigated in vivo in Sprague-Dawley rats with chemotherapy-induced mucositis. The best properties were obtained with the blend of TMC of 9.8% DS (5%) and GP (20%). EPO was released from the hydrogel during 8 h, and more than 30% of the drug still remained on the mucosa after 3 h of washing the buccal mucosa with phosphate buffer. TMC/GP mixture was characterized by antimicrobial properties. The EPO hydrogel demonstrated in vitro/in vivo wound-healing properties. Therefore, EPO-loaded hydrogel has the potential to be used in the treatment of OM and other oral or subcutaneous wounds.

Objective:This study was designed to compare the severity of gastrointestinal (GI) side effects in Type 2 diabetes mellitus (DM) patients receiving tablet or capsule forms of metformin.Methods:In this prospective interventional study, patients were evaluated from June to November 2016 at DM clinics affiliated to Isfahan University of Medical Sciences, Isfahan, Iran. Adult patients with Type 2 DM who were eligible for inclusion criteria switched from metformin tablet to metformin capsule. Hemoglobin A1c (HbA1c), GI side effects, and patient satisfaction based on visual analog scale (VAS) were assessed during a 6-week follow-up of receiving metformin capsule.Findings:One hundred and three patients were evaluated, and 75 patients participated in this study. At the baseline, 40 patients (53.3%) had GI side effects due to metformin tablet which was reduced to 16 patients (21.3%) after switching to metformin capsule (P = 0.001). There was also an improvement in HbA1c (from 7 to 6.8,P < 0.0001). The results of patients’ satisfaction based on VAS and numeric rating scale indicated that in 59 patients (78.67%), GI side effects were reduced after switching to metformin capsule (mean score: 7.2 with the range of 6–9) while 16 patients stated no treatment preference.Conclusion:Switching to metformin capsule may result in less GI side effects, with no further side effect complications.

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Ascorbyl palmitate formed vesicles in combination with cholesterol and a negatively charged lipid (dicetyl phosphate). Niosomes were prepared by the film hydration method, followed by sonication, in which aqueous doxorubicin solution (in phosphate buffer saline pH=7.4) was encapsulated in aqueous regions of lipid layers. Vesicle’s formation was confirmed by either scanning electron microscopy images or observation of unsonicated vesicles by light microscope. The percent efficiencies of doxorubicin encapsulation of the different formulations were determined by fluorescence spectrophotometry. Cholestrol content in niosomes did not exhibit any relation to vesicle size, zeta potential, percent entrapment, or release rate. Differential scanning calorimetric data of pure lipids, vesicle dispersion, and mixture of lipids confirmed the formation of niosomes.