A Novel Approach for Dry Powder Coating of Pellets with Ethylcellulose. Part II: Evaluation of Caffeine Release

Satranidazole-loaded chitosan/locust bean gum/xanthan gum polysaccharide composite multiunit pellets for colon targeting: in vitro–in vivo investigation

Background

The colon has a significant site to deliver numerous active materials for colonic diseases. Highly biodegradable polymers hold significant promise among the several techniques available to deliver the drug to the colon. This research aimed to prepare chitosan, locust bean gum and xanthan gum polysaccharide composite satranidazole multiunit pellets for colonic release and assesses the bioavailability with pharmacokinetic parameters after administration of satranidazole raw drug compared to multiunit pellets. Satranidazole multiple unit pellets were prepared based on chitosan, locust bean gum and xanthan gum, which were inexpensive and harmless. The bioavailability study was done by crossover design in which satranidazole raw drug and test formulation was administered to six healthy white albino rats.

Results

The pharmacokinetic analyses were estimated using the deconvolution of the plasma profile. Compared to the satranidazole drug used as a reference, for the pellets, the maximum plasma concentration was lower (35.02 ± 3.91 ng/ml vs. 51.07 ± 1.21 ng/ml for the satranidazole drug), and the time to attain maximum concentration was 2.50 ± 0.55 h for both drugs and test formulation. Colonic drug content was significantly higher than that of free administered drug.

Conclusion

The results indicate the acquired pharmacokinetic studies and colonic analysis established the reliability of the pharmaceutical technique and the ability to release satranidazole at the colonic site.

Graphical Abstract

Response surface method for optimization of prepared satranidazole powder layered pellets

Background

The purpose of the present study was to evaluate layered of satranidazole powder using natural polysaccharides as coating materials for colon targeting that were inexpensive and natural with a non-toxic nature using a composite response design of 3 levels and 2 factors for each of the four responses in the quadratic model. The independent variables were the ratio of coating consistency % (X1) and coating level % (X2) in the pellet. The dependent factors were % release of drug at 2 h. (Y1), % release of drug at 6 h. (Y2), % release of drug difference in presence & absence of colonic enzyme (Y3) and mean dissolution time (Y4). The various models were fitted for the responses with an explanation of suitable statistical methods. Variance analysis and different factor levels of responses were constructed by response surface plots.

Results

Satranidazole pellets were efficiently prepared by the variable amount of ingredients that showed compatibility with possible pellet characterization and drug dissolution profiles to optimize the formulation.

Conclusions

The strategy of response surface can be a successful tool for improving the prepared satranidazole pellets which can be an appropriate replacement of regular one.

Development and In Vitro/Ex Vivo Characterization of Vaginal Mucoadhesive Bilayer Films Based on Ethylcellulose and Biopolymers for Vaginal Sustained Release of Tenofovir

Young women in sub-Saharan Africa have the highest risk of human immunodeficiency virus (HIV) acquisition through sexual contact of all groups. Vaginal controlled release of antiretrovirals is a priority option for the prevention of sexual transmission of the virus in women. In this manuscript, bilayer films were prepared based on ethylcellulose and a natural polymer (xanthan or tragacanth gum) plasticized with glycerol and tributylcitrate for tenofovir-controlled release. The mechanical properties and microstructure of the blank films were characterized by texture analysis, Fourier transform infrared spectroscopy, and scanning electron microscopy. The loaded films were evaluated in simulated vaginal fluid through release and swelling studies and ex vivo mucoadhesion assessments. The results show that the preparation method produced bilayer films with adequate mechanical properties. The contribution of both layers allowed the sustained release of tenofovir and a mucoadhesion time of up to 360 h. The toxicity of the materials was evaluated in three cell lines of vaginal origin. The films constituted by ethylcellulose and xanthan gum in a 2:1 proportion (EX2-D) showed the longest mucoadhesion time, with 15 days of tenofovir-controlled release, zero toxicity, and optimal mechanical properties. These films are therefore a promising option for offering women a means of self-protection against the sexual transmission of HIV.

Rheological and Mechanical Investigation into the Effect of Different Molecular Weight Poly(ethylene glycol)s on Polycaprolactone-Ciprofloxacin Filaments

Fused deposition fabrication (FDF) three-dimensional printing is a potentially transformative technology for fabricating pharmaceuticals. The state-of-the-art technology is still in its infancy and requires a concerted effort to realize its potential. One aspect includes the processing parameters of FDF and the effect of formulation thereto, which, to date, have not been thoroughly investigated. To progress understanding, the effect of different molecular weight poly(ethylene glycol)s (PEG) on polycaprolactone (PCL) loaded with ciprofloxacin (CIP) was investigated. A rheometer was used, and adapted accordingly, to analyze three processing aspects pertaining to FDF: viscosity, solidification, and adhesion. The results revealed that both CIP and PEG affected all three processing parameters. The salient findings were that the ternary blend with 10% w/w PEG 8000 exhibited rheological and adhesive properties ideal for FDF, as it provided a desirably shear-thinning filament that solidified rapidly, and improved the adhesion strength, in comparison to both the PCL-CIP binary blend and other ternary blends. In contrast, the ternary blend with 15% w/w PEG 200 was unfavorable; despite having a greater plasticizing effect, whereby the viscosity was markedly reduced, the sample provided no benefit to the solidification behavior of PCL-CIP and, in addition, failed to display adhesive behavior, which is a necessity for a successful print in FDF. The original findings herein set the precedent that the effect of drug and PEG on FDF processing should be considered beyond solely modifying the viscosity.

An Artificial Neural Network Approach to Predict the Effects of Formulation and Process Variables on Prednisone Release from a Multipartite System

The impact of formulation and process variables on the in-vitro release of prednisone from a multiple-unit pellet system was investigated. Box-Behnken Response Surface Methodology (RSM) was used to generate multivariate experiments. The extrusion-spheronization method was used to produce pellets and dissolution studies were performed using United States Pharmacopoeia (USP) Apparatus 2 as described in USP XXIV. Analysis of dissolution test samples was performed using a reversed-phase high-performance liquid chromatography (RP-HPLC) method. Four formulation and process variables viz., microcrystalline cellulose concentration, sodium starch glycolate concentration, spheronization time and extrusion speed were investigated and drug release, aspect ratio and yield were monitored for the trained artificial neural networks (ANN). To achieve accurate prediction, data generated from experimentation were used to train a multi-layer perceptron (MLP) using back propagation (BP) and the Broyden-Fletcher-Goldfarb-Shanno (BFGS) 57 training algorithm until a satisfactory value of root mean square error (RMSE) was observed. The study revealed that the in-vitro release profile of prednisone was significantly impacted by microcrystalline cellulose concentration and sodium starch glycolate concentration. Increasing microcrystalline cellulose concentration retarded dissolution rate whereas increasing sodium starch glycolate concentration improved dissolution rate. Spheronization time and extrusion speed had minimal impact on prednisone release but had a significant impact on extrudate and pellet quality. This work demonstrated that RSM can be successfully used concurrently with ANN for dosage form manufacture to permit the exploration of experimental regions that are omitted when using RSM alone.