A novel approach for the quantification of paclitaxel loaded in ethyl cellulose/kollicoat and ethylcellulose/eudragit colloidal particles by UPLC-PDA.

An optimized rapid reversed phase ultra-performance liquid chromatography (UPLC-PDA) method has been developed and validated for precise and accurate quantification of paclitaxel in drug delivery systems. The chromatographic separation was attained on L1 (USP) column (2.1 ×50 mm, 1.7µm) with an isocratic mobile phase comprised of acetonitrile and water (1:1; flow rate 0.6 mL/min) and detection was executed at 227 nm by PDA detector. The proposed UPLC-PDA method is found to be rapid with retention time of 1.37 min, selective with homogenous peaks and sensitive with Limit of Detection (LOD) of 0.08µg/mL and Limit of Quantification (LOQ) of 2.6µg/mL. The method showed excellent linearity (R2>0.998) over the range of 0.1 to 0.4mg/mL and applied for the paclitaxel quantification in different formulations with no inference of excipients. Thus, the proposed approach has potential for rapid estimation of drug purity, assay and release profile from pharmaceutical preparations.

A novel approach for the quantification of paclitaxel loaded in ethyl cellulose/kollicoat and ethylcellulose/eudragit colloidal particles by UPLC-PDA.

An optimized rapid reversed phase ultra-performance liquid chromatography (UPLC-PDA) method has been developed and validated for precise and accurate quantification of paclitaxel in drug delivery systems. The chromatographic separation was attained on L1 (USP) column (2.1 ×50 mm, 1.7µm) with an isocratic mobile phase comprised of acetonitrile and water (1:1; flow rate 0.6 mL/min) and detection was executed at 227 nm by PDA detector. The proposed UPLC-PDA method is found to be rapid with retention time of 1.37 min, selective with homogenous peaks and sensitive with Limit of Detection (LOD) of 0.08µg/mL and Limit of Quantification (LOQ) of 2.6µg/mL. The method showed excellent linearity (R2>0.998) over the range of 0.1 to 0.4mg/mL and applied for the paclitaxel quantification in different formulations with no inference of excipients. Thus, the proposed approach has potential for rapid estimation of drug purity, assay and release profile from pharmaceutical preparations.

Enhanced gastric retention and drug release via development of novel floating microspheres based on Eudragit E100 and polycaprolactone: synthesis and in vitro evaluation.

Eudragit E 100 and polycaprolactone (PCL) floating microspheres for enhanced gastric retention and drug release were successfully prepared by oil in water solvent evaporation method. Metronidazole benzoate, an anti-protozoal drug, was used as a model drug. Polyvinyl alcohol was used as an emulsifier. The prepared microspheres were observed for % recovery, % degree of hydration, % water uptake, % drug loading, % buoyancy and % drug release. The physico-chemical properties of the microspheres were studied by calculating encapsulation efficiency of microspheres and drug release kinetics. Drug release characteristics of microspheres were studied in simulated gastric fluid and simulated intestinal fluid i.e., at pH 1.2 and 7.4 respectively. Fourier transform infrared spectroscopy was used to reveal the chemical interaction between drug and polymers. Scanning electron microscopy was conducted to study the morphology of the synthesized microspheres.

Swelling and aspirin release study: cross-linked pH-sensitive vinyl acetate-co-acrylic acid (VAC-co-AA) hydrogels.

The objective of this work was to develop new pH-sensitive hydrogels to deliver gastric mucosal irritating drugs to the lower part of the gastrointestinal tract. For this purpose, cross-linked vinyl acetate-co-acrylic acid (VAC-co-AA) hydrogels were synthesized by using N, N, methylene bisacrylamide (MBAAm) as a cross-linking agent. Different ratios of 90:10, 70:30, 50:50, 30:70, and 10:90 of VAC-co-AA were synthesized. All of the compositions were cross-linked using 0.15, 0.30, 0.45, and 0.60 mol percent MBAAm. Swelling and aspirin release were studied for 8 hour period. The drug release data were fitted into various kinetic models like the zero-order, first-order, Higuchi, and Peppas. Hydrogels were characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. In addition to the above, these hydrogels were loaded with 2%, 8% and 14% w/v aspirin solutions, keeping the monomeric composition and degree of cross-linking constant. In conclusion, it can be said that aspirin can be successfully incorporated into cross-linked VAC/AA hydrogels and its swelling and drug release can be modulated by changing the mole fraction of the acid component in the gels.

The Structural, Crystallinity, and Thermal Properties of pH-responsive Interpenetrating Gelatin/Sodium Alginate-based Polymeric Composites for the Controlled Delivery of Cetirizine HCl.

OBJECTIVES: The present work aimed to design and synthesize pH-sensitive cross-linked Ge/SA hydrogels using different ratios of each polymer, and to investigate the effect of each polymer on dynamic, equilibrium swelling, and in vitro release pattern of cetirizine hydrochloride, which was selected as a model drug. MATERIALS AND METHODS: These gelatin and sodium alginate hydrogels were prepared at room temperature through free radical polymerization using glutaraldehyde as a crosslinker. These polymeric composites were used as model systems to envisage various important characterizations. The in vitro release pattern of drug was investigated in three different mediums (phosphate buffer solution of pH 1.2, 5.5, 7.5 whose ionic strength was kept constant). Various structure property relationships that affect its release behavior were determined such as swelling analysis, porosity, sol-gel analysis, average molecular weight between crosslinks (Mc), solvent interaction parameter (χ), volume fraction of polymer (V2,s) and diffusion coefficient. The structural, crystallinity, and thermal stability were confirmed using FTIR, XRD, and DSC analysis. RESULTS: These hydrogels showed maximum swelling at pH 1.2. Zero-order, first-order, Higuchi, and Peppas models were applied to demonstrate the release pattern of drug. The release of drug occurred through non-Fickian diffusion or anomalous mechanism. Porosity was found increased with an increase in concentration of both polymers, and porosity decreased when the concentration of the crosslinker was increased. Gel fraction increased with an increase in concentration of SA, Ge, and glutaraldehyde. CONCLUSION: The prepared pH sensitive hydrogels can be used as a potential carrier for the sustained delivery of cetirizine hydrochloride.