ethyl cellulose

Among the drugs used in long-term cardiovascular management, carvedilol occupies a special position owing to its combined non-selective beta-blockade and alpha-1 receptor antagonism. However, turning this pharmacological advantage into consistent clinical benefit is not straightforward. The molecule belongs to BCS Class II, meaning it crosses biological membranes readily but barely dissolves in physiological fluids. On top of that, extensive hepatic extraction during the first pass through the liver trims oral bioavailability to somewhere between 25 and 35 percent, and an elimination half-life of only 6 to 10 hours forces patients to take the drug multiple times a day. Together, these characteristics create the conditions for erratic plasma concentrations, missed doses, and avoidable side effects. Encapsulating carvedilol within polymer-matrix microspheres is a strategy with growing experimental support: the polymer network acts as a physical throttle on drug escape, stretching the release window well beyond what any immediate-release tablet can offer. This article brings together evidence published between 2016 and 2025 on how microsphere formulations of carvedilol are built, what polymers are chosen and why, how the finished particles are tested, and what the most informative recent studies have found. Across this body of work, entrapment efficiencies consistently exceed 75 percent when formulation conditions are properly optimised, and release profiles extending to 12 hours or beyond are regularly achieved. Floating, pH-sensitive, and mucoadhesive variants each address specific absorption or tolerability concerns, broadening the design toolbox available to formulators.

Gout is a disease caused by the deposition of monosodium urate (MSU) crystals in tissue such as cartilage, synovial membranes, bones and skin which causes inflammation in the synovial tissue. Indomethacin is first line of drug used as NSAID for the treatment of Gout. The aim of this study was to encapsulate Indomethacin in ethyl cellulose microspheres and compare the efficiency of the formulated Indomethacin microspheres with the Marketed formulation. Indomethacin microspheres were prepared by solvent evaporation method. FTIR  studies revealed there was no significant interaction between the drug and polymer. Preformulation studies gave satisfactory results. SEM studies showed a spherical smooth microsphere average size of 10.4±3.04. The percentage entrapment efficiency and percentage drug release after 10 hours was found to be 82.97±1.6 % and 52.04±0.58 % respectively. The therapeutic effect of the Indomethacin microspheres was evaluated by the swelling of knee joints, joint range of motion and histologic analysis of MSU induced rat model. The prepared indomethacin microspheres showed effective prolong in the retention time of the drug in the intra articular cavity to 30 d which is more than that of the marketed formulation. Intra- articular injection of Indomethacin microspheres efficiently relieved inflammatory symptoms such as swelling index, joint range motion and suppressed inflammatory cell infiltration than the marketed formulation. Thus intra-articular injection of Indomethacin loaded microspheres proved to be a promising therapeutic method in the treatment of Gout.

The present work reports on the preparation of ethyl cellulose (EC)-pluronic F127 (PF127)-based tableted floating microspheres by the oil-in-water emulsion solvent evaporation method for the controlled release of acyclovir (ACV). Microspheres of this study were characterized by Fourier transform infrared (FTIR) spectroscopy to investigate the chemical interactions of ACV with the polymer, floating behavior, scanning electron microscopy (SEM) for morphology of the microspheres, differential scanning calorimetry (DSC) for investigating their thermal properties  and X-ray diffraction (XRD) as well as. In vitro release experiments of microspheres were performed in acidic pH 1.2 media to understand the release profiles of ACV. The selected sets of microspheres were compressed into tablets using the compressible excipients and their in vitro release performances were evaluated in pH 1.2 media.

The aim of this study was to prepare Diclofenac potassium (DP) microspheres by using Double Emulsion-solvent evaporation method with ethyl cellulose (EC) and Eudragit polymers. An attempt was made to formulate a sustained release dosage form of diclofenac potassium, to minimize frequent dosing as well as reducing or eliminating local side effects by avoiding the drug release in the upper gastro-intestinal tract Poly vinyl alcohol containing 2% (w/w) span 80 was the external phase and polymer -drug solution was the internal phase. EC and Eudragit were used to encapsulate diclofenac potassium. By using different formulation variables, six different formulations (F1, F2, F3, F4, F5, & F6) were prepared. The resulting microspheres obtained, were more spherical in shape and showed more entrapment efficiency. The size of the microspheres varied between 346-695 μm and as high as 96.24% loading efficiency for Eudragit and 82.34% for EC was obtained. In vitro release study was carried out in 0.1 N hydrochloric acid solution (pH 1.2) for first 2 hours followed by in phosphate buffer solution (pH 6.8) for next 4 hours. After first 2 hours of dissolution in 0.1 N hydrochloric acid, EC microspheres released 23% of drug and Eudragit released 7% of drug. The formulations were found to be effective in providing controlled release of drug for a longer period of time.

The aim of present investigation was to develop press coated tablet for pulsatile drug delivery of lornoxicam using hydrophilic and hydrophobic polymers. The drug delivery system was designed to deliver the drug at such a time when it could be most needful to patient of rheumatoid arthritis. The press coated tablets containing lornoxicam in the inner core was formulated with an outer shell by different weight ratio of hydrophobic polymer (ethyl cellulose) and hydrophilic polymers (sodium alginate). The release profile of press coated tablet exhibited a lag time followed by burst release, in which outer shell ruptured into two halves. The effect of formulation composition on the barrier layer comprising both hydrophobic and hydrophilic excipients on the lag time of drug release was investigated. It was observed that lag time decreases with increasing concentration of sodium alginate. The optimized formulation (F5) comprised 10: 90%w/w concentration ratio of sodium alginate: Ethocel 10 cps with a 245 mg coating weight, and showed a desired lag time of 308 minutes, which mimics the fluctuating symptoms of rheumatoid arthritis, followed by rapid release of lornoxicam.

One of the most feasible approaches for achieving a prolonged and predictable drug delivery profiles in the GIT is to control the gastric residence time (GRT) using gastroretentive dosage forms. The aim of the present study is to prepare the floating microspheres of ketoprofen to sustain the drug release for longer time to overcome the short half life of the drug. The microspheres were prepared by emulsification-solvent evaporation technique using ethyl cellulose and heat denaturation technique using egg albumin as a natural polymer. The optimization of microspheres was carried out based on pentagonal design using response surface methodology. The floating microspheres were evaluated for micromeritic properties, particle size, percentage yield, in-vitro buoyancy, entrapment efficiency, drug polymer compatibility, scanning electron microscopy and in-vitro drug release studies. The prepared microspheres exhibited prolonged drug release (> 9 h) and remained buoyant for > 24 h. The mean particle size increased and the drug release rate decreased at higher polymer concentration. The optimized formulation of ethyl cellulose microspheres (KEC-OP) exhibited prolonged drug release of 88.31 % up to 10 h demonstrating zero order kinetics and Case II transport release mechanism where as optimized formulation of egg albumin (KEA-OP) showed drug release of 96.78 % up to 9 h demonstrating peppas kinetics and Case II transport release mechanism.

The purpose of this research work was to prepare an extended release formulation of metoprolol succinate using Ion exchange resin. Metoprolol succinate has short half life of 3-7 hours. So it needs to be administered 3-4 times a day. Hence an extended release preparation is desired. Drug-resin complex (DRC) was obtained by loading metoprolol succinate onto a strong cation exchange resin, Indion 244 in the ratio 1.5:1 using batch method. The molecular properties of the complex were investigated by differential scanning calorimetry, X-ray powder diffraction and Infra red spectroscopy which revealed interaction of drug with resin. To achieve the desired release rate, the DRC was initially treated with an impregnating agent, polyethylene glycol (PEG) 4000 and was further treated with hydrophobic polymer ethyl cellulose. Various formulations of tablets using resinate were prepared to achieve desired drug release profile. The formulations were evaluated for hardness, friability, weight variation, in vitro release and assay using HPLC. Formulation (V) shows optimum results in terms of release profile, which were in accordance with the USP specifications. The in vitro release profile showed that complexation of drug with ion exchange resin and use of hydrophobic polymer matrix could retard the initial burst and extend the release of drug up to 24 hours.