Natamycin is the only drug approved for fungal keratitis treatment, but its low water solubility and low ocular penetration limit its efficacy. The purpose of this study was to overcome these limitations by encapsulating the drug in single or mixed micelles and poly(pseudo)rotaxanes. Soluplus and Pluronic P103 dispersions were prepared in 0.9% NaCl and pH 6.4 buffer, with or without α-cyclodextrin (αCD; 10% w/v), and characterized through particle size, zeta potential, solubilization efficiency, rheological properties, ocular tolerance, in vitro drug diffusion, and ex vivo permeation studies. Soluplus micelles (90–103 nm) and mixed micelles (150–110 nm) were larger than Pluronic P103 ones (16–20 nm), but all showed zeta potentials close to zero. Soluplus, Pluronic P103, and their mixed micelles increased natamycin solubility up to 6.00-fold, 3.27-fold, and 2.77-fold, respectively. Soluplus dispersions and poly(pseudo)rotaxanes exhibited in situ gelling capability, and they transformed into weak gels above 30 °C. All the formulations were non-irritant according to Hen’s Egg Test on the Chorioallantoic Membrane (HET-CAM) assay. Poly(pseudo)rotaxanes facilitated drug accumulation into the cornea and sclera, but led to lower natamycin permeability through the sclera than the corresponding micelles. Poly(pseudo)rotaxanes made from mixed micelles showed intermediate natamycin diffusion coefficients and permeability values between those of Pluronic P103-based and Soluplus-based poly(pseudo)rotaxanes. Therefore, the preparation of mixed micelles may be a useful tool to regulate drug release and enhance ocular permeability.

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Objetivo: Detectar personas con riesgo alto/muy alto de padecer diabetes y derivarlas al médico, evaluar en la muestra la prevalencia de los distintos factores de riesgo y realizar una intervención educativa mínima sobre éstos en todos los usuarios participantes. Material y métodos: Estudio observacional transversal realizado en noviembre de 2014. Se incluyeron usuarios de la farmacia, mayores de 18 años, no diagnosticados de diabetes y que aceptaron realizar la encuesta. Muestreo no probabilístico. Variable principal: puntuación obtenida en el cuestionario Findrisc. Otras: características demográficas, IMC, perímetro de cintura, glucemia capilar (si F≥15), medicación, intervención, tiempo empleado. Resultados: Participaron 90 farmacéuticos de las 17 comunidades autónomas. Realizaron 1.520 cuestionarios Findrisc. La puntuación media de la muestra fue de 10,9 (DE=5,1). El número de individuos con riesgo alto o muy alto fue de 370 (24,3%) de los 1.520 encuestados. 207, el 55,9% de aquellos y el 13,6% de la muestra total, tenían glucemia ≥110 mg/dL y se derivaron al médico. Existe relación directa entre el número de medicamentos utilizados y el riesgo de diabetes. El tiempo empleado en la intervención fue de 9,9 (DE=5,1) minutos. Conclusiones: El alto porcentaje de participantes con riesgo alto/muy alto de padecer diabetes que son derivados al médico de familia para valorar su situación, avala la eficiencia de la farmacia en este tipo de cribados. La intervención educativa realizada con los participantes supone una llamada de atención sobre la importancia del estilo de vida saludable orientado a la prevención de las enfermedades metabólicas.

The topical administration route is commonly used for targeting therapeutics to the eye; however, improving the bioavailability of drugs applied directly to the eye remains a challenge. Different strategies have been studied to address this challenge. One of them is the use of aggregates that are formed easily by self-assembly of cyclodextrin (CD)/drug complexes in aqueous solution. The aim of this study was to design a new eye drop formulation based on aggregates formed between CD/drug complexes. For this purpose, the physicochemical properties of the aggregates associated with six CDs and selected water-soluble polymers were analysed. Complex formation was studied using differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FT-IR) and 1H nuclear magnetic resonance spectroscopy (1H-NMR). Results showed that HPβCD performed best in terms of solubilization, while γCD performed best in terms of enhancing nanoaggregate formation. Formation of inclusion complexes was confirmed by DSC, FT-IR and 1H-NMR studies. A mixture of 15% (w/v) γCD and 8% (w/v) HPβCD was selected for formulation studies. It was concluded that formulations with aggregate sizes less than 1 µm and viscosity around 10–19 centipoises can be easily prepared using a mixture of CDs. Formulations containing polymeric drug/CD nanoaggregates represent an interesting strategy for enhanced topical delivery of nepafenac.

The aim of this study was to design and evaluate novel cyclodextrin (CD)-based aggregate formulations to efficiently deliver nepafenac topically to the eye structure, to treat inflammation and increase nepafenac levels in the posterior segment, thus attenuating the response of inflammatory mediators. The physicochemical properties of nine aggregate formulations containing nepafenac/γ-CD/hydroxypropyl-β (HPβ)-CD complexes as well as their rheological properties, mucoadhesion, ocular irritancy, corneal and scleral permeability, and anti-inflammatory activity were investigated in detail. The results were compared with a commercially available nepafenac suspension, Nevanac® 3 mg/mL. All formulations showed microparticles, neutral pH, and negative zeta potential (–6 to –27 mV). They were non-irritating and nontoxic and showed high permeation through bovine sclera. Formulations containing carboxymethyl cellulose (CMC) showed greater anti-inflammatory activity, even higher than the commercial formulation, Nevanac® 0.3%. The optimized formulations represent an opportunity for topical instillation of drugs to the posterior segment of the eye.