Design and evaluation of dry-coated tablets for colonic delivery of diclofenac sodium

A colonic drug delivery system is required to protect a drug during its transit through the upper gastro-intestinal tract and allow its release in the colon. The aim of this study was the preparation of dry-coated tablets designed for colonic release of the model drug Diclofenac sodium (DS). The system consists of a drug-pectine (PC) mixture as the core and hydroxypropylmethylcellulose (HPMC) alone or mixed in different ratios with poly(ε-caprolactone) (CL) as the coat layer

Study of dissolution rate enhancement of poorly water soluble drug

Aim of this work is the preparation of spray-dried microspheres as drug delivery systems for Rokitamycin (RK), using chitosan (C) and its salt, chitosan glutamate (CG) to improve the dissolution rate of the drug. The work further aimed to investigate the effect of the type of chitosan and feed solution concentration on the microsphere properties

<i>In vitro</i> and <i>in vivo</i> studies of artichoke extract (<i>Cynara scolymus</i> L.) as ketoprofen skin penetration enhancer

In this study, the enhancing effect of artichoke extract containing cynaropicrin on the in vitro and in vivo percutaneous absorption of ketoprofen from gels has been investigated

Improvement of antiamoebic activity of Rokitamycin loaded in chitosan microspheres

Rokitamycin is a new macrolide containing 16 carbon atoms, strongly inhibitory for Acanthamoeba castellanii, an opportunistic protozoa of humans which cause primarily amoebic keratitis and chronic, but fatal, amoebic granulomatous meningoencephalitis. Chitosan microspheres were prepared as carriers to obtain a controlled release of rokitamycin, able to improve the antiamoebic activity of this drug. The microparticles were in vitro characterised and the efficacy of rokitamycin alone and encapsulated into microspheres on the growth rate of Acanthamoeba castellani was evaluated. The results obtained suggest that spray-drying is a good technique for the preparation of microspheres loaded with rokitamycin. The loading of the drug into the polymeric network leads to an increase in the dissolution rate compared to drug raw material and improves and prolongs the in vitro antiamoebic activity of the drug. Thus, microspheres based on rokitamycin could be used in the therapy of systemic and topical infections caused by Acanthamoeba

Nanoparticles based on hydroxypropylcyclodextryn: preparation and in vitro viability study on Caco2 cells

The work purpose was to prepare and in vitro characterise solid nanoparticles based on hydroxypropyl-β-cyclodextrin (HP) by high pressure emulsification method; the effect on the viability of the formulations on Caco2 cells has been also evaluated

Spray-dried microspheres based on methylpyrrolidinone chitosan: <i>in-vitro</i> and <i>ex-vivo</i> studies

The purpose of this work was the preparation and the study of methypyrrolidinone chitosan spray-dried microspheres for the intranasal release of metoclopramide hydrochloride (Met). Chitosan (CH) microparticles were prepared as comparison

Neural network: an instrument to study flow and packing properties of pharmaceutical powders

In the present study five brands of microcrystalline cellulose (Ph101, Vivapur, Ph 301, Emcocel and Prosolv), three brands of Crospovidone (XL, XL-10 and INF) and pregelatinized Starch were mixed with 2% w/w of Aerosil 200, Aerosil R972 (two different kinds of colloidal silicon dioxide) or Mg stearate, to obtain 27 distinct mixtures. Flow rate, bulk and tapped density of mixtures were measured and tablets were prepared

Cellulose acetate phthalate-chitosan based nanoparticles for transdermal delivery of captopril in pediatric patients

The Pediatric Committee at the European Medicines Agency identified the needs of the development of age-appropriate formulation of captopril in pediatric population for the treatment of cardiovascular diseases and diabetic nephropathy. Captopril (CAT) is currently administered by extemporaneous liquid formulation or tablet due to its limited water stability. Therefore, polymeric nanoparticles were developed for transdermal delivery of CAT for obtaining a prolonged CAT release as well as an easy dosage control with high compliance of pediatric patients. Cellulose acetate phthalate (CAP) and chitosan (CH) were chosen to prepare nanoparticles by nanoprecipitation method-dropping technique without using surfactants. CAP nanoparticles and CAP nanoparticles combined with CH in different concentrations (1:1 w/w and 1:3 w/w) were produced both unloaded and loaded with CAT. Nanoparticles were characterized in terms of size, drug loading efficiency and physical stability during the time (1-28 days). Chemical stability of drug in the dispersion was investigated. Results show that CAP nanoparticles have no drug loading capacity, whereas CH allows the encapsulation of CAT; highest drug loading is obtained when 1:3 CAP:CH w/w ratio was used (64.6±7.6%). The particle preparation at 60°C enhances the interaction of CAT with the polymer matrix. The size of loaded CAP nanoparticles is 515.6±5.2 nm, whereas that of CAP-CH nanoparticles is 279.8±2.5 nm (1:1 w/w ratio) and 408.1±9.5 nm (1:1 w/w ratio) with a PDI values around 0.2, resulting in a homogeneous system. Good physical stability of all formulations during the time is observed. At the moment, CAT appears stable in the dispersions. In conclusion, CAP-CH nanoparticles prepared using a 1:3 w/w ratio show good properties for developing suitable formulation for transdermal delivery of CAT