Release Retarding Polymer Research Articles

Optimization In-vitro Evaluation and Scratch Wound Healing Assay of Hexacosane Topical Gel for Wound Healing.

The compounds hexocosane, a sterol hydrocarbon identified in the dichloromethane extract and isolated from marine sponges of the genus Agelas. Hexocosane possesses anti-inflammatory and antioxidant activities that reduce inflammation and oxidative stress, they promote cell proliferation and angiogenesis, facilitating tissue regeneration and repair. This multifaceted approach makes this secondary metabolite a promising candidate for developing advanced wound care therapies that effectively address both infection control and wound healing. On the basis of viscosity, in-vitro release, and skin retention, optimal gel formulations were developed with hexocosane (1%) to achieve the best results. A response surface methodology Box-Behnken design was applied on three factors and three levels [carbopol 940 (1, 1.25 and 1.5%), hydroxypropyl methylcellulose (HPMC) (1,1.5 and 1.2%), and propylene glycol (0–1–1.5% and 1–2%, respectively] using three factors and three levels. In order to assess the spreadability and viscosity, a glass slide and a Brookfield viscometer were used. An assay was conducted to determine how topical gel affects wound healing. The optimization study of the gel formulation, involving variations in adhesive polymer (Carbopol 940), release retarding polymer (HPMC K4M), and penetration enhancer (Surfactant), has identified three noteworthy formulations (F4, F8 & F14). Each formulation is characterized by specific attributes such as viscosity, in-vitro drug release, and skin retention. All samples were found to elicit significant wound healing efficacy as evidenced from the representative photomicrographs. The maximum efficacy was elicited by formulation (F4) with 100 mg drug at the time duration of 36 hours.

Formulation and evaluation of Mesalamine mini-tablets in enteric-coated capsule for the treatment of ulcerative colitis using a factorial design approach

The Enteric Capsule Drug Delivery Technology (ECDDT) was designed to enable oral administration while ensuring complete enteric protection and swift release in the upper gastrointestinal (GI) tract, without the need for coatings. Current study used a 32factorial design (Stat-Ease Design Expert v12) to formulate a mini-tablet in an enteric-coated capsule to treat ulcerative colitis utilising ECDDT and mini-tablets. Mesalamine, an amino salicylate, was used as a model drug to study the effects of independent variables like HPMC K4M as a release retarding polymer at 10-20% and Crospovidone as a super disintegrant at 2-5% on in vitro drug release to meet desired Q points of dissolution. higher value of Tmax (10 Hours) and T1/2 (9 Hours) was observed for the Optimized formulation with Cmax value of (35.24 ± 0.45 ng/mL), AUC (0-48) (411.58 ± 1.45 hr.ng/mL) and Ke (0.077 ± 0.010 hr-1) it may be due to delayed release formulation.

Formulation, design, and evaluation of valsartan sodium-sustained-release matrix tablets

The main aim of present work was to formulate and evaluate sustain release matrix tablets of Valsartan, an angiotensin II Receptor type 1 antagonist. Sustain release formulation are those which delivers the drug locally or systemically at a predetermined rate for a fixed period of time. The matrix tablet was prepared by direct compression method using by various concentration of chitosan and sodium alginate with combination of various release retardant polymer. The powder mixtures were subjected to various pre-compression parameters such as angle of repose, bulk density, tapped density and Carr’s index shows satisfactory result and the compressed tablets are evaluated for post-compression parameters such as weight variation, thickness, hardness, friability, drug content, in-vitro dissolution and stability studies. In-vitro dissolution studies were carried out for 24 hours using 0.1N HCl for first 2 hours and pH 6.8 phosphate buffers for 24 hours and the result showed that formulations F4 and F7 showed good dissolution profile to control the drug release respectively. Formulation containing higher concentration of chitosan and sodium alginate along with polymers sustainedthedrugreleasefor theperiodof24hours.The compatibilityof thedrug, polymers and other excipients were determined by FT-IR Spectroscopy. Results showed that the drug was compatible with polymers and other excipients. The release data was fitted to various mathematical models such as Zero-order, First-order, Higuchi equation and Korsmeyer- Peppas model to evaluate the kinetics and the drug release. The drug release followed first order and the mechanism was found to be non-Fickian. The stability studies were carried out for 3 months and result indicates that the selected formulations (F4and F7) were stable.

Exploring the Effectiveness of Carboxymethylated and Crosslinked Albizia procera Gum in Diltiazem Hydrochloride Matrix Tablets: A Comparative Analysis.

This study investigates the efficacy of modified Albizia procera gum as a release-retardant polymer in Diltiazem hydrochloride (DIL) matrix tablets. Carboxymethylated Albizia procera gum (CAP) and ionically crosslinked carboxymethylated Albizia procera gum (Ca-CAP) were utilized, with Ca-CAP synthesized via crosslinking CAP with calcium ions (Ca2+) using calcium chloride (CaCl2). Fourier Transform (FT) IR analysis affirmed polymer compatibility, while differential scanning calorimetry (DSC) and X-ray diffraction (XRD) assessed thermal behavior and crystallinity, respectively. Zeta potential analysis explored surface charge and electrostatic interactions, while rheology examined flow and viscoelastic properties. Swelling and erosion kinetics provided insights into water penetration and stability. CAP's carboxymethyl groups (-CH2-COO-) heightened divalent cation reactivity, and crosslinking with CaCl2 produced Ca-CAP through -CH2-COO- and Ca2+ interactions. Structural similarities between the polymers were revealed by FTIR, with slight differences. DSC indicated modified thermal behavior in Ca-CAP, while Zeta potential analysis showcased negative charges, with Ca-CAP exhibiting lower negativity. XRD highlighted increased crystallinity in Ca-CAP due to calcium crosslinking. Minimal impact on RBC properties was observed with both polymers compared to the positive control as water for injection (WFI). Ca-CAP exhibited improved viscosity, strength, controlled swelling, and erosion, allowing prolonged drug release compared to CAP. Stability studies confirmed consistent six-month drug release, emphasizing Ca-CAP's potential as a stable, sustained drug delivery system over CAP. Robustness and accelerated stability tests supported these findings, underscoring the promise of Ca-CAP in controlled drug release applications.

In-vivo study of Budesonide mini-tablets in enteric coated capsules for the treatment of ulcerative colitis

Budesonide, a corticosteroid, was used as a model drug to study the effects of independent variables like HPMC K4M as a release retarding polymer at 2-6% and Crospovidone as a super disintegrant at 2-5% on in vitro drug release to meet desired Q points of dissolution. Current study used a 32 factorial design (Stat-Ease Design Expert v12) to formulate a mini-tablet in an enteric-coated capsule to treat ulcerative colitis utilising ECDDT and mini-tablets. An in vivo study was conducted in New Zealand rabbits to determine the pharmacokinetic parameters for the optimized formulation (BF4-O). Time vs. plasma concentration plots of the Pure drug and Optimized formulation was observed. Plotted Area under the curve indicates the extent of drug absorption inside the body. Pharmacokinetic analysis of Budesonide pre drug plasma concentration–time data provided the following pharmacokinetic parameters like Cmax value ranging (1.42 ± 2.12 ng/mL), Tmax value (4.0 Hours), AUC value (12.77 ± 0.15 h.ng/mL), Half Life (3.5 Hours) and other pharmacokinetic parameters are depicted. Study demonstrates the variability in pharmacokinetic parameters like Tmax, Cmax, T1/2 (Hours), AUC and Ke. Henceforth, the newly developed Mini-Tablet in Enteric Coated capsule could be utilized clinically for the treatment of Ulcerative Colitis, alternatively with cost-effectiveness.

Formulation and Evaluation of Floating Microspheres

Gastro-retentive dosage forms have potential for use as controlled- release drug delivery systems. Gastro retentive floating drug delivery systems have a bulk density lower than that of gastric fluids and thus increase residence time of drug in stomach and provide controlled delivery of many drugs. The aim of the present study is formulation and characterization of floating microspheres using model drug. Floating microspheres were prepared by oil-in-water emulsion solvent evaporation technique using ethyl cellulose as release retarding polymers. The floating microspheres were evaluated for percentage yield (%), particle size, drug content, drug entrapment efficiency, in-vitro floating ability and in-vitro drug release studies. The surface morphology of prepared microspheres was characterized by scanning electron microscopy. The microspheres were found to be spherical in shape and porous in nature. Compatibility studies were performed by fourier transform infrared (FTIR) technique. The prepared microspheres showed prolonged drug release of 12 h and remain buoyant for more than 12 h. In-vitro release kinetics were studied in different release kinetics models like zero order, first order model. It was concluded that developed floating microspheres offers a suitable and practical approach for prolonged release of drug over an extended period of time and thus oral bioavailability, efficacy and patient compliance is improved

Formulation and Evaluation of Nifedipine Bilayer Floating Tablets

In the present investigation concern, the formulation and evaluation of bilayer floating tablet of Nifedipine which after an oral administration increase gastric residence time, to increase the bioavailability. Nifedipine is the Calcium channel blocker of the dihydropyridine type which used in angina pectoris and hypertension. It has a half-life of 2-4hours and bioavailability of 45-56%. It is advantageous to formulate bilayer floating tablet of Nifedipine helps to increase bioavailability, reduce dosing frequency, and reach maximum plasma concentration rapidly. Bilayer floating tablets comprised of two layers, immediate and sustain release layers. The immediate release layer is comprised of super disintegrating agent Karaya gum, and sustain release layer comprised of low density release retardant polymers like HPMC K4M and Guar gum; and sodium bicarbonate and citric acid gas generating agents. The prepared powder mixtures were subjected to FT-IR for all interaction. The tablets were prepared by direct compression. First, the powder blends of sustained release layer was pre-compressed and then powder blends of immediate release layer was added. Hardness, friability, drug content, floating lag time, total floating time, swelling index and in-vitro drug release were evaluated. In the present study, it was found that formulation F4 containing HPMC K4M and Guar gum in the ratio of 2:1 showed maximum drug release. The release data were adjusted to various mathematical models such as Higuchi, 1st order and zero order to evaluate the kinetics and mechanisms of the drug release and it was best suited for the Higuchi model. There were no notable changes in stability studies.

Formulation and Evaluation of Floating Microspheres of Sitagliptin

Gastro retentive dosage forms have potential for use as controlled- release drug delivery systems. Gastro retentive floating drug delivery systems have a bulk density lower than that of gastric fluids and thus increase residence time of drug in stomach and provide controlled delivery of many drugs. The aim of the present study is formulation and characterization of floating microspheres using Sitagliptin as a model drug for the management of type-2 diabetes mellitus. Floating microspheres were prepared by oil-in-water emulsion solvent evaporation technique using ethyl cellulose and eudragit S-100 as release retarding polymers. The floating microspheres were evaluated for percentage yield (%), particle size, drug content, drug entrapment efficiency, in-vitro floating ability and in-vitro drug release studies. The surface morphology of prepared microspheres was characterized by scanning electron microscopy. The microspheres were found to be spherical in shape and porous in nature. Compatibility studies were performed by fourier transform infrared (FTIR) technique. The prepared microspheres showed prolonged drug release of 12 h and remain buoyant for more than 12 h. In-vitro release kinetics were studied in different release kinetics models like zero order, first order, higuchi and korsmeyer peppas model and the best fit model was found to be higuchi plot with release exponent n value less than 0.89. It was concluded that developed floating microspheres of Sitagliptin offers a suitable and practical approach for prolonged release of drug over an extended period of time and thus oral bioavailability, efficacy and patient compliance is improved.

NANOSPONGE HEALING APPROACH FOR TREATMENT OF STREPTOCOCCAL GANGRENE

Objective: The envisaged research work aims to develop a nanosponge loaded gel for the treatment of Streptococcal gangrene. Methods: In the present study, permeability is enhanced by targeted drug release formulation of topical clindamycin phosphate nanosponges were prepared by emulsion solvent diffusion method using ethyl cellulose as release retardant polymer and PVA as surfactant or emulsifier. Nanosponges were prepared by emulsion solvent diffusion method by changing drug polymer ratio (1:0.05, 1:0.1, and 1:0.15) and process parameters were optimized using 32 full factorial central design. CP nanosponges were then incorporated into a hydrogel prepared using Carbopol 934. Results and Discussion: The drug loaded nanosponges were evaluated for physical appearance, drug content, entrapment efficiency, and particle size. Characterization of CP nanosponges was done by SEM for the formulation. In vitro release study indicated that the release of CP varied according to the concentration of matrix forming polymer. The best standardized formulation G5 and G6 were further evaluated for microbiological studies. Microbial studies were done using Staphylococcus aureus as the strain organism and the activity of the gel against the organism was evaluated by measuring the zone of inhibition. It was also found to be stable for 2 months during its stability studies. Conclusion: Thus, it was concluded that CP can be formulated as nanosponge hydrogel that can release the drug up to 24 h with increased permeability and targeted release. Therefore, clindamycin phosphate nanosponges prepared are promising drug delivery for topical application as being more useful than conventional formulation therapy.

Exploration, Development and Optimization of Eco-friendly Novel Dosage Form – Pastilles

Background: Now-a-day, there is the need to explore the concept of green chemistry in every field. Many existing conventional and novel drug delivery systems have problems related to green chemistry. To overcome the existing limitations of the different dosage forms, a newer untouched dosage form pastilles was explored. Objective: The present study aims to optimize the Glipizide (GPZ) matrix pastilles using waxy erodible polymers integrating the concept of quality by design (QbD) and green chemistry. Methods: The pastilles were formulated using the fabricated lab-scale pastillator. GPZ was used as a model drug. The concern related to the drug is low aqueous solubility and short variable half-life. The solubility of the drug was improved by formulating a complex between GPZ and chemically modified ß –cyclodextrin (β-CD) - hydroxypropyl-ß-cyclodextrin (HP- ß -CD). The complex was prepared using the kneading method. The complex was formulated incorporated different stoichiometric ratios of GPZ: complexing agent. Sustained-release pastille formulated using Gelucire 43/01 (GC 43/01) as release retardant polymer. The central composite design had been used to obtain an optimum batch, using the amount of GC 43/01 and temperature as independent variables, while drug release at 2h, 6h, and 10h was chosen as dependent variables. Design batches were evaluated for post-and preformulation parameters. An optimum formulation was evaluated for the influence of hydroalcoholic media on drug release. Results: The complex formulated using HP- ß –CD (1:1) shown better solubility (36.5mg/ml) and dissolution. The complex was incorporated in the pastilles with erodible polymer GC 43/01. The formulation was found robust with optimum pre and post formulation parameters. Optimized batch was chosen from the design space of central composite design. The drug release of the optimized formulation was found 29.13%, 57.29% and 85.70% at 2, 6 and 10 hrs respectively which was similar to the drug release of the marketed formulation. As the amount of alcohol increased from 5 to 40 %, the drug release also increased but did not show a dose dumping effect. It is just due to the altered solubility of GPZ in alcohol. Conclusion: The untouched formulation, Pastilles of GPZ were developed incorporating the waxy erodible polymer. Pastilles were capable to control drug release up to 12 h. The amount of GC 43/01 and temperature had a significant effect on the formulation of GPZ sustained-release pastille. The newer approach of formulating pastilles might apply to the industry as it is an eco-friendly, single-step process and uses fewer excipients.

Formulation and Evaluation of Sotalol Gastrorententive Tablets

The objective of this study was to formulate floating tablets (GRDDS) of Sotalol using direct compression method to increase its bioavailability and the gastric residence time of the dosage form. The Sotalol tablets were prepared by direct compression method. The tablets were prepared by using different types of polymers i.e.; Sodium CMC, Chitosan and Psyllium Husk which act as a release retardant polymer. Sodium bi carbonate (NaHCO3) was used as a gas degenerating agent and MCC (Micro crystalline cellulose) was used as a diluent. The prepared formulation were subjected to some evaluation parameters like hardness, friability, weight variation, drug content, buoyancy property, drug release study etc. In the FT-IR study it was revealed that there is no interaction between the drug and excipients. The formulation which containing Chitosan polymer and Sodium bicarbonate shows good drug release pattern with less floating lag time and good floating duration. The in vitro drug release pattern of Sotalol floating tablets was fitted to different kinetic models which showed the highest regression for Higuchi order kinetics. Thus, it can be concluded that the floating drug delivery system of Sotalol using the appropriate polymers in right amount may enhance the activity of the drug by prolonging the gastric residence time or reducing the floating lag time.

Development and optimization of floating alginate microspheres of repaglinide using Box-Behnken experimental design

Background: Due to short-lasting action, fast clearance and enzymatic instability of anti-diabetic drugs result in low bioavailability as they are mainly absorbed from the stomach and the lower part of the gastrointestinal tract. The bioavailability of antidiabetic drugs can be significantly increased by enhancing the gastric residence time using gastroretentive drug delivery systems such as floating microspheres.
 Objectives: The present investigation deals with the development and optimization of floating microspheres for gastroretentive delivery containing repaglinide using Box-Behnken design and also investigates the effect of different process variables on the formation of the microsphere. Thereby, increasing the bioavailability and reducing the mentioned side effects of repaglinide.
 Materials and methods: Floating microspheres of repaglinide formulated by ionic gelation method and optimized using Box-Behnken design. The independent variables were the concentration of Hydroxy methylcellulose (HPMC) (A), Sodium alginate (B), and calcium chloride (C) while entrapment efficiency (R1), swelling index (R2), and in vitro drug release (R3) were considered as dependent variables. The optimized formulation of floating microspheres was characterized by various physicochemical properties, surface morphology, drug excipient interaction, in vitro release, and buoyancy studies.
 Results: Based on obtained 3D response surface plot factors A, B, and C were found to give a synergistic effect on R1, while factor A has a negative effect on R2. Interaction of AC was negative on R1 and R2 but positive on R3. The interaction of AC and BC was negative in all the responses. Scanning electron microscopy (SEM) revealed that microspheres were spherical with nearly smooth surface morphology. Good entrapment and buoyancy were observed for 12 h. The in vitro drug release was found to be controlled for more than 12 hours and followed the Higuchi model. The validations of response surface methodology (RSM) for three dependent variables were 100.09%, 99.68%, and 97.02%.
 Conclusion: Repaglinide floating microspheres were prepared and optimized by use of Box – Behnken process optimization software. The quantitative responses of particle size, entrapment efficiency, and in vitro drug release for different combinations of independent variables, sodium alginate as release retarding polymer, HPMC K100M as floating polymer, and calcium chloride as a cross-linking agent were obtained experimentally, and the results were found to fit the design model. The quantitative effect of these factors at different levels on the responses could be predicted using polynomial equations, and high linearity was observed between predicted and actual values of response variables. The results of the present study showed that the responses i.e, particle size, entrapment efficiency, and in vitro release are significantly affected by the concentration of polymer and a cross-linking agent. The formulation OF1 was found to be the optimum formulation predicted by the point prediction of the design expert software. The in vitro drug release was found to be controlled for more than 12 h and followed the Higuchi model. The validations of RSM for three dependent variables were 100.09%, 99.68%, and 97.02%. Therefore, it can be concluded that a floating microsphere for repaglinide was developed and optimized using a three-factor, three-level Box – Behnken design.

Formulation and Evaluation of Controlled Release Tablet of Irbesartan

The main aim of present work was to formulate and evaluate controlled release matrix tablets of Irbesartan. It releases drugs at fixed and expected rate in a controlled manner either by dissolution and diffusion control mechanism. The matrix tablet was prepared by wet granulation method using by various concentration of HPMC and ethyl cellulose with combination of various release retardant polymer. The powder mixtures were subjected to various pre- compression parameters such as angle of repose, bulk density, tapped density and Carr’s index shows satisfactory result and the compressed tablets are evaluated for post- compression parameters such as weight variation, thickness, hardness, friability, drug content and in- vitro dissolution studies. In- vitro dissolution studies were carried out for 24 hours using 0.1N HCL for first 2 hours and ph 6.8 phosphate buffers for 24 hours and the result showed that formulations F3 and F4 show good dissolution profile to control the drug release respectively. The drug content of the formulation was determined by using 0.1 N HCL at 262nm. The drug content was maximum with formulation F5 and minimum with formulation F3.

Formulation and In-Vitro Evaluation of Sustained Release Pilocarpine Ocuserts Using Modified Karaya Gum Extracted from Sterculia urens

Ocular inserts of Pilocarpine nitrate (PN) were prepared using modified karaya gum (MKG) alone as release retarding polymer and in combination with the copolymer sodium alginate. Modification of the karaya gum was done by treating it with the trisodium trimetaphosphate (STMP) by cross linking method and evaluated for its physicochemical properties. Films of the MKG were prepared by employing solvent casting method using varying concentrations (600mg, 500mg and 400mg) of MKG and the sandwiching technique was used for the loading of drug. Sodium alginate (SA) and PN blend were prepared by triturating their appropriate amounts. Six ocusert formulations (F1-F6) were prepared with different concentrations of the polymer i.e MKG and SA while the amount of PN was kept constant in formulations. Formulations F1-F3 contained the MKG alone in varying concentrations (600mg, 500mg and 400mg) and F4-F6 contained SA (0.5 mg) in addition to MKG. The surface pH of prepared ocuserts from the formulations (F1-F6) was in the range of 6.63 to 6.8. Thickness range of the ocuserts was from 0.21 to 0.32 mm. Dissolution profiles of prepared ocuserts were studied and drug release was found within the range of 69.2± 1.36 % (F4, minimum) to 90.5± 3.21% (F3, maximum). Overall results of the study concluded that ocuserts fabricated with MKG and SA at optimized concentrations have the potential to sustain the release of PN and therefore reducing dosing frequency and adverse effects.

Pilot-scale binder jet 3D printing of sustained release solid dosage forms

The additive nature and versatility of 3D printing show great promise in the rapid prototyping of solid dosage forms for clinical trials and mass customization for personalized medicine applications. This paper reports the formulation and process development of sustained release solid dosage forms, termed “printlets”, using a pilot-scale binder jetting (BJT) 3D printer and acetaminophen (APAP) as the model drug. With the inclusion of hydroxypropyl methylcellulose (HPMC) as a release retardant polymer in the print powder, the drug release time of APAP increased considerably from minutes to hours. However, given the swelling propensity of HPMC, a thicker layer of powder must be laid down during printing to avoid any shape distortion of the printlets. For a fixed print volume, the level of binder saturation (i.e., ratio between the liquid binder and powder in the as-printed sample) is inversely proportional to the thickness of the spread powder layer. An increase in the spread powder layer inadvertently resulted in a lower level of binder saturation and consequently weaker printlets. By increasing the level of binder saturation with jetting from more print heads, the mechanical strength of printlets containing 18% HPMC was successfully restored. The resultant printlets have a drug release time of 3.5 h and a breaking force of 12.5 kgf that is comparable to the fast-disintegrating printlets containing no HPMC and surpasses manually pressed tablets with the same HPMC content.

Preparation and Characterization of Calcium Cross-linked Carboxymethyl Tamarind Kernel Polysaccharide as Release Retardant Polymer in Matrix

This study aims to improve the efficacy of carboxymethyl tamarind kernel polysaccharide by cross-linking with Ca2+ ion and preparing its diclofenac sodium loaded matrix tablets for sustained drug delivery applications. Ionic gelation technique was used for cross-linking, and calcium chloride was used as a cross-linking agent. The native and cross-linked polysaccharide was characterized to analyze the change. The successful cross-linking of calcium was confirmed by infrared spectra by evaluating change in the functional group, while diffraction patterns revealed the change in crystallinity behavior. The thermal property of modified gum was also improved after Ca2+ cross-linking, whereas microscopical images of both gums revealed the gum's change in shape and surface. Further, calcium cross-linked carboxymethyl tamarind kernel polysaccharide was formulated into a matrix tablet using diclofenac sodium. The weight variation, thickness, hardness, friability, content uniformity, moisture content, swelling index, and in vitro release kinetics were also evaluated. The in vitro release study revealed that modified gum tablets showed a sustained release of diclofenac sodium providing a release of 50.84 % of drug over 24 hours, following first-order kinetics with a super case – II transport mechanism. So, the results indicate that calcium cross-linking of CMTKP modifies its release behavior, making it suitable for preparing sustained release pharmaceutical formulation.

FORMULATION AND IN-VITRO CHARACTERIZATION OF ABACAVIR SULPHATE EFFERVESCENT FLOATING TABLETS

fter oral administration of Abacavir, rapid absorption occurs from upper part of gastro intestinal tract with peak concentrations occurring at 0.63 - 1 hr after dosing. Conventional drug therapy with tablets produce relatively rapid and high peak blood levels that requires frequent administration to maintain effective range of plasma drug levels. This conventional therapy leads to reduced effectiveness with poor therapeutic management. To overcome the inadequacy of conventional therapy with tablets, floating sustained release Abacavir tablets were developed. Floating sustained release Abacavir Sulphate tablets were prepared by using direct compression method. Tablet were formulated using Ethyl Cellulose with hydrocolloids like Hydroxypropyl Methylcellulose (HPMC K4M) and Carbopol 974P as release retarding polymers, Sodium bicarbonate (NaHCO3) and Citric acid as effervescent agents. Tablets were then evaluated for various physical parameters including hardness, thickness, weight variation, friability, drug content, in-vitro buoyancy, Swelling index and Invitro gastro retentive drug release were conducted. Drug and excipient compatibility studies show that they are compatible with each other. The optimized formulation (F9) shows the hardness of 5.7kg/cm2, tablet thickness of 2.74mm, 0.45% of friability, in-vitro buoyancy was up to 6 hours and % drug release was 90.56% in 6 hours. Drug release kinetics was found to follow non-fickian diffusion. Hence, F9 is considered as optimized formulation based on invitro buoyancy and % drug release.

Sustained release matrix tablet of 100 mg losartan potassium: Formulation development and in vitro characterization

Sustained release matrix tablets of 100 mg losartan potassium HCl were fabricated with two release retarding polymers namely HPMC K100 M and affinisol by direct compression method. Nine trial formulations were prepared by varying content of these polymers, each from 50 mg to 100 mg; keeping the total weight of the tablet 310 mg. The best formulation was selected based on in vitro drug release profile for 12 hours conducted in Type II dissolution apparatus at 50 rpm and water as dissolution medium. Pre-compression parameters such as bulk density, tap density, Carr’s index and Hausner ratio were evaluated for the selected tablet. The tablets were subjected to thickness, weight variation test, drug content, hardness and friability. Drug release kinetics, surface morphology and accelerated stability study were investigated for that selected formulation. Formulation F4 with the composition of 75 mg HPMC K100M and 100 mg affinisol was selected as the best formulation that extended the drug release up to 12 hours. Pre-compression parameters and other tableting properties were within the Pharmacopoeia limit. Release kinetics analysis proved non-fickian zero-order drug release and that was further confirmed by surface morphology of the tablets before and after dissolution study visualized by SEM. The developed formulation was found to be stable for one month stored at 60 ○C.

Synthesis and Characterization of calcium Starch: A New Controlled Release Polymer for floating tablets of Losartan Potassium

Losartan potassium is used to treat high blood pressure (hypertension). The present study was aimed to prepare a floating drug delivery system to design a controlled release oral dosage form of Losartan potassium. This helps to overcome the demerit of limited residence time of the drug in the gastrointestinal track and hence to increase the duration of release. Hence objective of the present study is to develop Losartan potassium floating tablets by direct compression method using calcium starch as release retarding polymer. The calcium starch was synthesized by gelatinizing potato starch in the presence of sodium hydroxide and cross linking by treatment with calcium chloride. The micromeritic properties studies indicated that calcium starch is a promising pharmaceutical excipient in tablets. Floating tablets of Losartan potassium was formulated by direct compression technique, using different concentration of calcium starch and compared with HPMC K-100 as release retard polymer. As the amount of calcium starch in the tablet increased, the drug release decreased. The formulation F5 containing 125 mg calcium starch showed better controlled release of 76.38% after 12 hours.

FORMULATION AND EVALUATION OF DRUG RELEASE PROFILE OF HYDROPHILIC POLYMER BASED INDOMETHACIN PROLONG RELEASE MATRIX TABLETS

An oral modied release dosage forms have always been more effective therapeutic alternative to conventional dosage forms. The present invention is directed to a modied release pharmaceutical composition of indomethacin by using hydrophilic release retardant polymers like HPMC K15M, Na CMC alone or in combination. Matrix embedded prolong release tablet formulations of Indomethacin were prepared by wet granulation technique and evaluated for tablet properties such as the thickness, hardness, friability, weight variation, drug content, drug release kinetics and in vitro release studies. The inuence of drug polymer ratio on drug release was studied by dissolution test. The FTIR studies showed no interactions among drug and polymers. The tablets formulation (F7 and F8) containing combined polymers of HPMC K15M and Na CMC resulted in slower drug release rate form the matrix. So, it can be concluded that Indomethacin prolong release tablets using HPMC K15M and Na CMC as the retardant has successfully extended the release of indomethacin from its formulations. The mixing of two cellulose polymers, ionic and non-ionic, for the formulation of hydrophilic matrices, resulted in a valuable decrease in drug release rate. All the formulations showed KorsmeyerPeppa’s model as a best t.