Synthesis and Characterization of Carboxymethyl Chitosan Nanosponges with Cyclodextrin Blends for Drug Solubility Improvement

This study aimed to enhance the solubility and release characteristics of docetaxel by synthesizing highly porous and stimuli responsive nanosponges, a nano-version of hydrogels with the additional qualities of both hydrogels and nano-systems. Nanosponges were prepared by the free radical polymerization technique and characterized by their solubilization efficiency, swelling studies, sol-gel studies, percentage entrapment efficiency, drug loading, FTIR, PXRD, TGA, DSC, SEM, zeta sizer and in vitro dissolution studies. In vivo toxicity study was conducted to assess the safety of the oral administration of prepared nanosponges. FTIR, TGA and DSC studies confirmed the successful grafting of components into the stable nano-polymeric network. A porous and sponge-like structure was visualized through SEM images. The particle size of the optimized formulation was observed in the range of 195 ± 3 nm. The fabricated nanosponges noticeably enhanced the drug loading and solubilization efficiency of docetaxel in aqueous media. The drug release of fabricated nanosponges was significantly higher at pH 6.8 as compared to pH 1.2 and 4.5. An acute oral toxicity study endorsed the safety of the system. Due to an efficient preparation technique, as well as its enhanced solubility, excellent physicochemical properties, improved dissolution and non-toxic nature, nanosponges could be an efficient and a promising approach for the oral delivery of poorly soluble drugs.

ENHANCEMENT OF SOLUBILITY AND BIOAVAILABILITY OF BCS CLASS-II AMBRISENTAN: IN VITRO, IN VIVO AND EX VIVO ANALYSIS

Objective: The aim of this investigation was to enhance the solubility and bioavailability of the BCS class II poorly water-soluble drug ambrisentan by solid dispersion (SD) techniques using Gelucire 50/13 as a hydrophilic carrier. Methods: Solid dispersion of ambrisentan was prepared by kneading method using different dug: carrier ratios. Prepared SD was characterized for solubility, drug content, percentage yield, in vitro dissolution, ex vivo permeation and bioavailability. Solid-state characterization was performed by differential scanning calorimetry (DSC), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results: All the SDs formulations showed increase in drug solubility and dissolution when compared with its pure form. Aqueous solubility of the drug was found to be increased 8.23 fold in SD. DSC study showed that endothermic peak of the drug was disappeared in spectra of SD, confirming its amorphous conversion, XRD study revealed the reduction to almost absence of specific high-intensity peaks of drug which confirmed the reduction of crysatallinity of ambrisentan in SD. SEM of optimized SD formulation demonstrates the complete encapsulation and solubilization drug. In vitro dissolution study showed that optimized SD formulation (ASD4) gives the faster drug release of 101.5% in 60 min, as compare to its pure form and other SD formulations. Conclusion: Solid dispersion ASD4 prepared with 1:4 drug to carrier ratio showed the highest drug solubility and in vitro dissolution. The ex vivo and in vivo studies performed on optimized formulation ASD4 showed enhancement in drug permeability and bioavailability in Gelucire 50/13 based SD formulation.

DESIGN, DEVELOPMENT AND EVALUATION OF MOUTH DISSOLVING TABLETS OF TOFACITINIB CITRATE

Objective: This study aims to Formulate Mouth Dissolving Tablets (MDTs) of Tofacitinib Citrate with the increase in bioavailability and patient compliance. Methods: Mouth Dissolving Tablets (MDTs) of Tofacitinib Citrate were developed by full factorial design at 32levelsand prepared by direct compression method using super integrants like sodium starch glycolate, Ludiflash. The tablets were compressed into compacts on a 10 station tablet machine. The bulk drug was characterised by determining, MP, Solubility, pH and FTIR spectra. Results: The weight variation, hardness and diameter, thickness, friability, drug content, wetting time, in vitro disintegration time and in vitro dissolution studies, and stability study, tablet thickness, weight variation and drug content post compression parameters remained consistent and reproducible. All the formulations showed, almost 100 percent of drug release within 75 min. Formulations F1, F2 and F3 were prepared with 5 mg of SSG and 20 mg, 30 mg, and 40 mg Ludiflash which shows % release of drug in the order of F1<F2<F3. Formulations F4, F5 and F6 were prepared with 10 mg of SSG and 20 mg, 30 mg, and 40 mg Ludiflash which shows % release of drug in the order of F4<F5<F6. Formulations F7, F8 and F9 were prepared with 15 mg of SSG and 20 mg, 30 mg, and 40 mg Ludiflash which shows % release of drug in the order of F7<F8<F9. Conclusion: It is concluded that the amount of superdisintegrants decreases disintegration time of tablets, decreases wetting time, increases the cumulative % drug release causes better absorption.

FORMULATION AND DEVELOPMENT OF FIXED-DOSE COMBINATION OF BI-LAYER TABLETS OF EFAVIRENZ, LAMIVUDINE AND TENOFOVIR DISOPROXIL FUMARATE TABLETS 600 MG/300 MG/300 MG

Objective: This study is to formulate bi-layer tablet as a multidrug regimen against each reference listed drugs of Brand SUSTIVA® (efavirenz tablets 600 mg), EPIVER®(lamivudine tablets 300 mg), and VIREAD®(tenofovir disoproxil tablets 300 mg) to treat human immunodeficiency virus (HIV) infections. Which provides highly active antiretroviral therapy to provide effective treatment. Methods: Bilayer formulation was developed with each blend of layer-I (efavirenz) and layer-II (lamivudine and tenofovir disoproxil fumarate) through wet granulation process and roller compaction process, respectively. Further, both layers were compressed by using bi-layer compression followed by film coating. Layer-I and II formulations were developed by using various concentrations of diluents, surfactants, and disintegrants to improve the solubility of efavirenz and improve the flowability and uniformity of layer-II. Finally, the optimum formulation was developed to compare the in vitro dissolution with each branded formulation. Results: Drug-excipients interaction results revealed that the mixtures of three drug substances in 50 °C/75 % relative humidity (RH) resulted in an increase in tenofovir IMP-E and the highest unknown impurity was significantly increased and additionally decreased tenofovir assay in the presence of efavirenz. Sodium lauryl sulfate is very critical and it acts as a wetting agent and increases the solubility of efavirenz, and directly influences the dissolution of a drug product. Microcrystalline and croscarmellose sodium have a chance to affect the dissolution and friability of tenofovir. Powdered cellulose was acting as a diluent and flow property of the lamivudine part and it also affects the uniformity and dissolution. So, these ranges were optimized. X-ray diffraction (XRD) indicates there are no polymorphic changes for the optimized formulation and there is no interaction between the three active substances, and finally, in vitro dissolution results for the optimized formulation against the reference drugs. Conclusion: Optimum formulation yielded consistent drug release against each branded drug to treat human immunodeficiency virus (HIV1) infections. This formulation is robust and easily scale up for the next stage.

DESIGN, OPTIMIZATION, AND EVALUATION OF RAFT FORMING GASTRO RETENTIVE DRUG DELIVERY SYSTEM OF LAFUTIDINE USINGBOX–BEHNKEN DESIGN

Objective: The current research was aimed to formulate and evaluate raft forming gastro retentive floating drug delivery systems of Lafutidine for improving gastric residence time and sustained drug release for an extended time. Methods: Using Box–Behnken experimental design 17 formulations of lafutidine GRDDS were designed and evaluated for various parameters like physical appearance, pH, In vitro gelling study, in vitro buoyancy study, measurement of viscosity, density measurement, gel strength, drug content, acid neutralization capacity, the profile of neutralization, in vitro dissolution, release kinetic and stability studies. Results: All the evaluations were performed and observed that the values were within range, and the buoyancy lag time ranged within 14.76 to 25.84 sec and the formulations remained buoyant for more than 8h with the gelling time of 12h, the drug content was ranging from 98.96 to 99.55 %, and in vitro release was 86.86 to 99.34% by the end of 12h. The release kinetics followed zero-order with Higuchi’s model that indicating that drug release was found to be followed by the matrix diffusion process. Conclusion: Out of all formulations F3 was the optimized formulation and it was further characterized for FTIR, DSC, and stability studies, which exposed that there were no interactions amongst drug and excipients and no major change in the formulation and found to be stable.

FORMULATION, OPTIMIZATION, AND CHARACTERIZATION OF TRANSDERMAL DRUG DELIVERY SYSTEMS CONTAINING EPLERENONE

Objective: The proposed work was aimed at optimization, formulation, and characterization of transdermal patches of eplerenone for efficient transdermal delivery of the drug. Methods: The log p estimation of eplerenone is 1.34, it was closer to standard worth. Log P value in a range of 1 to 4 indicates higher permeation through the skin. FTIIR study was carried out individually for drug, each polymer, and finished product (Patches) compared eplerenone and FTIR spectra of pure drug and polymer. The calibration curve of eplerenone in Phosphate buffer pH 6.8 was analyzed. Results: The selected range of eplerenone was found to be linear. A regression coefficient (R2) at 245 nm was found to be 0.994. Drug content outcomes additionally discovered uniform in all clusters in a range of 97 % to 98 %, that batches arranged with ERS 100 show great mechanical properties contrast with different polymers however helpless glue properties. The flatness of 4 cm2 patches ranges from 348±0.087 mg to 387±0.527 mg. skin irritation it was produced irritation with negligible erythema following 10 d and unequivocal erythema, promptly obvious edema was produced following 12 d. Conclusion: These after-effects of the in vivo skin irritation study recommended that advanced batch S9 doesn't show any kind of significant disturbance on rodent skin for as long as 14 d and it was securely utilized around 24 h. the optimized batch S9 drug was constantly discharged through the Wistar rodent skin up to 16 hr and the delivery design was like an in vitro dissolution profile of the market product.

Mucilage of Coccinia grandis as an Efficient Natural Polymer-Based Pharmaceutical Excipient

Natural eco-friendly materials are recently employed in products to replace synthetic materials due to their superior benefits in preserving the environment. The herb Coccinia grandis is widely distributed in continents like Asia and Africa and used traditionally to treat fever, leprosy, asthma, jaundice, and bronchitis. Mucilage of Coccinia grandis was accordingly extracted, isolated by a maceration technique, and precipitated. The mucilage was evaluated for its physicochemical, binding, and disintegrant properties in tablets using paracetamol as a model drug. The crucial physicochemical properties such as flow properties, solubility, swelling index, loss on drying, viscosity, pH, microbial load, cytotoxicity was evaluated and the compatibility was analyzed using sophisticated instrumental methods (TGA, DTA, DSC, and FTIR). The binding properties of the mucilage was used at three different concentrations and compared with starch and PVP as examples of standard binders. The disintegrant properties of mucilage were used at two different concentrations and compared with standard disintegrants MCCP, SSG, and CCS. The tablets were punched and evaluated for their hardness, friability, assay, disintegration time, in vitro dissolution profiles. In vitro cytotoxicity studies of the mucilage were performed in a human embryonic kidney (HEK) cell line. The outcome of the study indicated that the mucilage had good performance compared with starch and PVP. Further, the mucilage acts as a better disintegrant than MCCP, SSG and CCS for paracetamol tablets. Use of a concentration of 3% or less demonstrated the ability of the mucilage to act as a super disintegrating agent and showed faster disintegration and dissolution, which makes it as an attractive, promising disintegrant in formulating solid dosage forms to improve the therapeutic efficacy and patient compliance. Moreover, the in vitro cytotoxicity evaluation results demonstrated that the mucilage is non-cytotoxic to human cells and is safe.

Solid Dispersion Preparation by Different Methods to Improve Solubility & Dissolution Simvastatin

The improvement of a pure drug's solubility and dissolution rate in the treatment of hyperlipidemia. Simvastatin is a 5-percent absolute bioavailability selective competitive inhibitor of HMG Co-A reductase. For the selection of the carrier, a preliminary solubility investigation of solid dispersion was performed, and solid dispersion was made using Hydroxy Propyl Methyl Cellulose (HPMC) and gum acacia. Solid dispersion of medication with polymer was created and studied for solubility and in-vitro dissolution profile. Solid dispersion of drug with polymer has shown an increase in solubility and improved dissolution rate. On the obtained formulations, further FTIR, X-Ray, Scanning electron microscopy, and Differential scanning calorimetry experiments were conducted. The existence of amorphous form in a solid dispersion made with polymer in a 1:5 ratio is verified by characterization research. The research also showed that using a solid dispersion approach with Polymer, the dissolving rate of a pure medication may be significantly increased.

Evaluation of in vitro Dissolution Profile and Physicochemical Characterization of Polymer Based Formulations of Sparingly Soluble Rosuvastatin

Rosuvastatin (RVT) is a BCS class II antilipidemic crystalline drug, which exhibits low bioavailability due to its very poor aqueous solubility; therefore, it is challenging to develop a proper formulation of RVT. To enhance solubility and bioavailability of this API, an attempt has been made by implementing solid dispersion technique. Solid dispersion (SD) technique is a solubility enhancing technique where one or more active entities are dispersed in an inert medium (matrix or carrier) at solid state. In this study, different ratios of Kollicoat® IR (KIR) and Kollidon® 90F (KF90) polymers were used with API to prepare various formulations by physical mixing (PM) and SD approaches; here solvent evaporation technique was used whereas methanol was used as solvent which was completely evaporated from the homogenously dispersed system by placing in a water-bath at 60-65°C and then in oven for 30 minutes at 50 °C. Among the formulations, RVT-KF90 SD formulations showed the most promising result in in-vitro study in terms of drug release profile (78.04 – 99.21%) in comparison to pure RVT (63.1%) and physical mixing of RVT with those polymers. USP dissolution apparatus type II was used at 37°C ± 0.5°C with 50 rpm to conduct the in-vitro experiment. The experiment also unraveled that the dissolution of RVT improved with increasing the amounts of polymers. Subsequently, stability of the developed formulations was conducted by Fourier transforms infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) as well as scanning electron microscopy (SEM). The results obtained from FTIR ensured no involvement of any significant drug-excipient interaction. Moreover, the DSC study signified thermal stability at high temperature. Besides, the SEM micrograph illustrated homogenous distribution of RVT in the polymer and transformation of crystal-like RVT into amorphous formulations. Dhaka Univ. J. Pharm. Sci. 20(2): 199-211, 2021 (December)

Formation of Self-Assembled Liquid Crystalline Nanoparticles and Absorption Enhancement of Ω-3s by Phospholipids and Oleic Acids

This study aimed to optimize and evaluate self-assembled liquid crystalline nanoparticles (SALCs) prepared from phospholipids and oleic acid for enhancing the absorption of ω-3s. We explored the structure and optimal formulation of SALCs, which are composed of ω-3 ethyl ester (ω-3 EE), phospholipids, and oleic acid, using a ternary diagram and evaluated the improvement in ω-3 dissolution, permeation, and oral bioavailability. The in vitro dissolution and pharmacokinetics of ω-3 SALCs were compared with those of Omacor soft capsules (as the reference). The shape of the liquid crystal was determined according to the composition of phospholipids, oleic acids, and ω-3s and was found to be in cubic, lamellar, and hexagonal forms. The dissolution rates of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) obtained from ω-3 SALCs were 1.7 to 2.3-fold higher than those of the Omacor soft capsules. Furthermore, a pharmacokinetic study in male beagle dogs revealed that ω-3 SALCs increased the oral bioavailability of ω-3 EE by 2.5-fold for EPA and 3.1-fold for DHA compared with the reference. We found an optimal formulation that spontaneously forms liquid crystal-based nanoparticles, improving the bioavailability of EPA and DHA, not found in the existing literature. Our findings offer insight into the impact of nanoparticle phase on the oral delivery of oil-soluble drugs and provide a novel ω-3 EE formulation that improves the bioavailability of EPA and DHA.