Polyox WSR Research Articles

EFFECT OF VARIOUS SUSTAINED RELEASE POLYMERS ON FLOATING TABLETS OF CARVEDILOL PHOSPHATE-A COMPARATIVE STUDY

Objective: This study aimed to develop floating tablets of Carvedilol phosphate containing various excipients such as HPMC K100M, Carbopol, Polyox WSR, HPMC K4M, and sodium bicarbonate to generate gas. Additionally, the impact of DCP, spray dried lactose, and HPβCD on drug release was investigated. Methods: A total of eighteen formulations were prepared using the direct compression method and evaluated for hardness, drug content, friability, floating lag time, floatation time and drug release properties. Results: FTIR analysis confirmed that there were no chemical interactions between Carvedilol phosphate and the excipients used in the formulation of the floating tablets. Most of the Carvedilol phosphate floating tablets, except for F9 and F10, did not disintegrate in water, alkaline fluids (pH 7.4), or acidic aqueous solutions (pH 1.2). These tablets exhibited satisfactory quality attributes in terms of hardness, drug content, and friability, making them suitable for sustained release. The floating lag time of the tablets ranged from 25 seconds to 34 min, while the floating duration varied from 2 to 24 h. The drug release from the tablets was gradual and sustained over 12 h, depending on the composition of the tablets. Polyox WSR (F9 and F10) resulted in a rapid drug release, whereas an increase in the polymer concentration led to a decrease in the rate of drug release across all formulations. Conclusion: The study reveals that the use of hydrophilic polymers enhanced the drug release, whereas hydrophobic polymers decreased the drug release. As such, formulations, F11, F15, and F16, which gave 100% drug release within 12 h are finalized as the optimized formulations of Carvedilol phosphate floating tablet.

Turbulent flow-driven liquid-solid mass transfer in serpentine tube heat exchanger/reactors: applications and implications

ABSTRACT This study examines liquid-solid mass and heat transfer rates in serpentine tube heat exchangers/reactors under turbulent flow using the copper dissolution technique. Key factors include solution flow rate, properties, tube diameter, U-bend curvature, and drag-reducing polymers. An empirical correlation predicts mass transfer coefficients, which are 4.12–5.36 times higher than straight tubes. Serpentine tubes show potential for economically viable diffusion-controlled reactions. Drag-reducing polymer (Polyox WSR-301) reduces corrosion rates by up to 23.3%. The study highlights serpentine tubes’ applicability in catalytic continuous reactors and membrane processes, emphasizing their significance in heat exchanger design and corrosion allowance prediction.

Formulation development and characterization of dual drug loaded hot-melt extruded inserts for better ocular therapeutic outcomes: Sulfacetamide/prednisolone

The present investigation was intended to formulate and evaluate a hot-melt extruded (HME) bioadhesive ophthalmic inserts containing a fixed-dose combination of Prednisolone Sodium Phosphate (PSP) and Sulfacetamide Sodium (SA) to improve the treatment outcomes of multiple ocular bacterial infections. The inserts were prepared using FDA-authorised biocompatible polymers, including Polyox WSR N10 LEO NF (polyethylene oxide; PEO), Klucel™ HF (hydroxypropyl cellulose; HPC-HF), and Ethocel™ (Ethylcellulose; EC). The inserts were then assessed for physicochemical characteristics, weight variation, surface pH, uniformity of thickness, drug content, swelling index, thermal analysis, drug–excipient compatibility, moisture uptake and loss, surface morphology, mucoadhesive strength, in vitro release, ex-vivo transcorneal permeation and deposition, and stability. The HPC-HF and EC-containing inserts extended the release of both drugs compared to PEO-N10-based inserts that showed the release of the loaded amount of both drugs immediately (<1 h). All fabricated inserts were stable over 90-day storage at room temperature (25 °C) and accelerated conditions (40 °C) for drug content and thermal behavior. The developed PSP-SA inserts exhibited optimum bioadhesive strength and smooth surface favorable for topical ocular application. Ex vivo transcorneal permeation studies using freshly isolated rabbit corneas demonstrated that the extended-release inserts slowed down the transcorneal flux of the drug in comparison to the immediate-release inserts and the commercial solution eyedrops. Overall, the inserts were fabricated using a solvent-free, scalable, and continuous manufacturing process and could reduce the frequency of administration to once-daily application, affording a new topical delivery vehicle with prolonged antibacterial and anti-inflammatory activity during ocular bacterial infections treatment.

Design and Optimization of a Polyethylene Oxide-Based Matrix Tablet of Metoprolol Succinate Using Design Expert Software

Hypertension is a common lifestyle disorder, the prevalence of which advances with age. In the case of antihypertensive therapy, patient compliance is hampered, especially in geriatric patients, if the dose is b.i.d or more, as it is difficult for the patient to remember and take medicine at a scheduled time. The present study involves the fabrication of a sustained-release matrixdesigned tablet using a combination of polyethylene oxide (PEO) polymers and metoprolol succinate as the model drug. The tablet is optimized and evaluated for its in-vitro release using the Design expert software. Polyethylene oxide is a non-ionic hydrophilic polymer which is directly compressible. Polyox WSR 301 and 303 grades have been used in the study to get the desired sustained release of 12 h. The formulations were analysed for various pre-compression and post-compression characteristics. The polymers Polyox WSR 301 and 303 influence drug release are measured using a 32 factorial design where the concentration of drug released at various time points has been analysed statistically as a response. Response surface plots demonstrate and depict the effect of the variables, thus aiding in optimization. All the formulated batches exhibited acceptable pre and post-compression characteristics. The optimized formulation M05 showed a sustained drug release up to a 12 h period. Thus polyethylene oxide can be used as an excellent sustained-release matrix polymer due to its ability to gel and prolong drug release from a matrix. Due to their molecular weight, a combination of two grades of polyethylene oxide helps reinforce the drug release.

Formulation and Evaluation of Floating-pulsating Drug Delivery System containing Fixed-dose Combination for Chronotherapy of Hypertension

This project aims to build a floating, pulsatile hypertension therapy. This work examined the 3-factor, 2-level box-behnken design and optimization technique for the floating pulsatile tablet. The quantity of polyox WSR N12K and polyox WSR205 was chosen to be the independent variable. Drug release, lag time, and swelling index are chosen to function in terms of dependent variables. ANOVA was intended to assess the data statistically, and p-value of 0.05 was regarded to have statistical significance. The tablet containing bisoprolol fumarate (BF) and hydrochlorothiazide (HCTZ) was chosen for preparation. The system comprises of 2 parts: an outer layer comprised of an erodible material with a gas-generating agent and a center core tablet holding the active medicinal component. Super disintegrants and active ingredients are to be used to prepare rapid release core tablets (RRCT). The improved formulation’s release kinetics provided the best fit for the zero-order models. The floating-pulsatile release (FPRT) F13 revealed a lag-time of 4 hours with &gt; 90% of the drug being released at level 0 (65 mg) for polyox (WSR-205) and level +1 (65 mg) for polyox (WSR-N12K). After the burst, drug release is restricted. The tablets floated well and released drug for 6 hours. The concept of floating pulsatile is to be applied to improve retention in a gastric environment of dosage forms that have a lag phase after bursts release.

Design and Development of Gastro-retentive Drug Delivery System for Trazodone Hydrochloride: a Promising Alternative to Innovator's Controlled-Release Tablet.

Trazodone hydrochloride (TZN) is a serotonin reuptake inhibitor that treats a major depressive disorder. It exhibits a short plasma half-life of 4.1 h and shows pH-dependent solubility. Above its pKa (6.74), solubility of TZN is very low, affecting its dissolution in the lower part of GIT. Hence, the present work aimed to develop gastro-retentive floating tablet of TZN. Central composite design was employed to optimize the formulation. Formulation variables like the concentration of HPMC-K100M, Polyox WSR 303 Leo, and sodium bicarbonate were evaluated for the responses like floating lag time and drug release. X-ray imaging study was performed on rabbits to determine the in vivo gastric retention of the optimized formulation. The accelerated stability study was conducted on optimized tablets as per ICH guidelines. Floating lag time and f2 value of the optimized formulation were found to be 2.51±0.02 min and 62.79, respectively. X-ray imaging studies in rabbits determined the in vivo gastro retention time. After 12 h of administration, tablet remained in the gastric region, indicating better retentive power. Accelerated stability studies showed sufficient formulation stability even after 3 months of storage. All these studies depict that the floating gastro-retentive system could be used as an alternative to the innovator formulation.

Development of ibuprofen tablet with polyethylene oxide using fused deposition modeling 3D-printing coupled with hot-melt extrusion

Ibuprofen is known to plasticize several polymers used in hot-melt extrusion, and it is considered challenging to achieve immediate release for ibuprofen using fused deposition modeling. Therefore, this study aimed to print ibuprofen tablets with a focus on achieving rapid release. Polyethylene oxide (Polyox WSR N80) was used as the main matrix to form the ibuprofen filament, because of its water-soluble properties and ability to manifest suitable mechanical properties, even with high drug loading (40% w/w). Several release modifiers, such as Kollidon VA64, Kollidon 12PF, Kollicoat IR, Kollidon CL, and mannitol, were added separately to the formulation, following which their effects on enhancing the drug release rate were investigated. Their effects on the mechanical properties of the filaments have also been assessed in this study. It was demonstrated that adding soluble Kollidon grades, such as Kollidon VA64 and Kollidon 12PF, enhanced the drug release rate. In addition, the tablet design with a high surface-to-mass ratio was beneficial for increasing the drug release rate. However, incorporation of the release modifiers discussed above decreased the flexural modulus of the filament. Additionally, it is important to tailor the printing parameters by considering the properties of the filament, to acquire good quality printlets. The tablet consisting of 30% ibuprofen and 20% Kollidon VA64 at the highest dose used in this study (84 mg) released 80% of the drug, in approximately 90 min. To further increase the release rate and drug dose, other additives, such as viscosity-increasing agents and reinforcing additives, can be explored. This study shows the potential of fabricating ibuprofen tablets with rapid release characteristics using Polyox WSR N80, via fused deposition modeling 3D-printing.

Formulation and evaluation of gastroretentive drug delivery system of eprosartanmesylate

It had became a challenging experience and effort for a formulator to develop and innovate a drug with maximum bioavailability. Objective: In the present study the focus of research is in the treatment of Hypertension, which is one of the most prevalent cardiovascular diseases in the world, affecting a big proportion of the adult and old age population. Eprosartan mesylate(EPM) is angiotensin-II receptor antagonist used for the treatment of high blood pressure. The drug has poor bioavailability due to limited oral absorption and maximum absorption at proximal intestine. This warrants and offers the use of Gastro Retentive Drug Delivery System (GRDDS) for sustained release formulation in order to achieve prolonged action and to improve patients compliance. Method: Wet granulation technique was selected for preparation of tablets and the drug is formulated with hydroxyl propyl methyl cellulose K100m, hydroxyl propyl methyl cellulose K15m, polyox WSR coagulant, polyox WSR301,polyox WSR N80, Lactose Monohydrate, Micro crystalline cellulose(Avicel), magnesium sterate, ethylcellulose, sodium bicarbonate, tromethamine, etc. Results: For around twenty formulations were made and evaluated for General appearance, Thickness, Hardness or Crushing strength Test, Friability Test, Estimation of drug content.

Influence of Print Settings on the Critical Quality Attributes of Extrusion-Based 3D-Printed Caplets: A Quality-by-Design Approach.

Extrusion-based 3D-printing is an easy-to-use, cheap manufacturing technique that could be used to produce tailored precision medicines. The technique has an almost unlimited versatility since a multitude of print parameters can easily be adapted. Unfortunately, little is known of the effect of these print parameters on the critical quality attributes of the resulting printlets. In this study, practical guidelines and means to adapt certain parameters in order to achieve the desired outcome (e.g., acceptable visual quality and flexible dosing) are stipulated for medical 3D-printing using a design-of-experiments approach. The current study aims at elucidating the effect of five print parameters (infill, overlap, number of shells, layer height and layer pattern) on the mechanical properties, dimensions, weight, porosity and dissolution characteristics of a fixed-size caplet consisting of Eudragit EPO (69.3%), Polyox WSR N10 (29.7%) and zolpidem hemitartrate (1%). In terms of the mechanical properties, 3D-printed caplets possessed anisotropy where the vertical compression strength and Brinell hardness exceeded the diametral strength. In general, all 3D-printed caplets possessed acceptable mechanical strength except for a small region of the knowledge space. Dimensional analysis revealed small, statistical significant differences between different runs, although the clinical relevance of this variation is likely negligible. The weight or dose of a caplet can be varied mainly using the infill and overlap and, to a lesser extent, via the layer height and number of shells. The impact on porosity was complicated as this was influenced by many factors and their interactions. Infill was the only statistically relevant factor influencing the dissolution rate of the current formulation. This study unravels the importance of the print parameter overlap, which is a regularly neglected parameter. We also discovered that small dose variations while maintaining the same dissolution profile were possible via modifying the overlap or number of shells. However, large dose variations without affecting the dissolution behaviour could only be accomplished by size modifications of the printlet.

A comparative study between the effect of swirl flow and axial flow on the rate of diffusion controlled corrosion in a double tube heat exchanger

ABSTRACT The rate of diffusion-controlled corrosion of an annulus under swirl flow was studied by measuring the limiting current of the cathodic reduction of potassium ferricyanide depolarizer in the presence and absence of polyox WSR-301 drag-reducing polymer. It was found that the rate of diffusion-controlled corrosion of the inner cylinder of the annulus increases with increasing swirl flow solution velocity and decreases with increasing the active height of the cylinder. The data in the absence of polymer (blank solution) under swirl flow were fitted by a dimensionless equation. The importance of this equation in predicting the rate of diffusion-controlled corrosion and the corrosion allowance during the design of the swirl flow equipment was highlighted. For a given set of conditions, the rate of accelerated swirl flow corrosion was much higher than that of axial flow. Drag reducing polymer was found to inhibit the rate of diffusion-controlled corrosion by a maximum of 23%, if other benefits of the polymer are considered such as the decrease in the shear stress and the associated decrease in the erosion-corrosion tendency besides the decrease in pressure drop and pumping power requirement it may be concluded that the use of drag-reducing polymers in industry is worthwhile.

Development of a 3D-Printed Dosing Platform to Aid in Zolpidem Withdrawal Therapy.

The long-term use of benzodiazepine receptor agonists (BZRAs) is associated with multiple side effects, such as increased sedation, hangover or an elevated risk of dependency and abuse. Unfortunately, the long-term use of BZRAs is reaching worrying intake rates, and therefore, the need for action is high. It was demonstrated already that the overall willingness of patients for deprescription increased when a slow dose reduction scheme with the possibility for dose increase, if needed, is employed. The current study aims to develop a flexible dosing platform of zolpidem hemitartrate (ZHT) to facilitate such withdrawal therapy. As this is the first report on the extrusion and 3D printing of ZHT, its thermal behaviour and sensitivity towards photolytic degradation was characterised. It was shown that ZHT possesses multiple polymorphs and was especially prone to oxidative photolysis. Next, a variety of immediate release polymers (Eudragit EPO, Kollidon VA64, Kollidon 12PF and Soluplus) were blended and extruded with Polyox WSR N10 to investigate their feedability and printability by mechanical and rheological analysis. The addition of PEO was shown to enable printing of these brittle pharmaceutical polymers, although the processing temperature was deemed critical to avoid surface defects on the resulting filaments. An EPO(70)PEO(30) system was selected based on its suitable mechanical properties and low hygroscopicity favoring ZHT stability. The matrix was blended with 1% or 10% API. The effect of certain printing parameters (caplet size, nozzle diameter, % overlap) on dissolution behaviour and caplet weight/dimensions/quality was assessed. A flexible dosing platform capable of delivering <1 mg and up to 10 mg of ZHT was created. Either caplet modification (incorporation of channels) or disintegrant addition (Primojel, Explotab, Ac-Di-Sol, Primellose and Polyplasdone-XL) failed to achieve an immediate release profile. This study provides the first report of a 3D-printed flexible dosing platform containing ZHT to aid in withdrawal therapy.

FORMULATION AND EVALUATION OF METFORMIN HYDROCHLORIDE AND GLICLAZIDE SUSTAINED RELEASE BILAYER TABLETS: A COMBINATION THERAPY IN MANAGEMENT OF DIABETES

Objective: The main objective of the present investigation is to develop a sustained-release (SR) formulation to optimize the postprandial elevation of glucose level in type 2 Diabetic subjects using combination therapy. In the present research work, bilayer sustained release formulation of metformin hydrochloride (MFH) and gliclazide (GLZ), based on monolithic-matrix technology was developed and evaluated. Methods: The formulations of metformin hydrochloride layer and gliclazide layer that contain polyox WSR coagulant and different viscosity grades of hydroxyl propyl methylcellulose (HPMC) as sustained-release matrix were prepared by direct compression and wet granulation method respectively. The bilayer tablets were prepared after carrying out the optimization of metformin layer and evaluated for various pre-compression and post-compression parameters. For the best formulation selected on basis of in vitro evaluation of tablets, Fourier-transform infrared spectroscopy (FT-IR) studies and comparison of in vitro dissolution profile of developed formulation with the innovator were performed. Results: Metformin hydrochloride and gliclazide showed sustained release of drug by diffusion mechanism and followed first-order kinetics. The best formulation of metformin hydrochloride (M7) and gliclazide (G8) show 99.93% and 99.65% of drug release in 24 h respectively. The similarity factor (f2) was 79.95 for metformin hydrochloride and 73.62 for gliclazide when compared with the innovator. Conclusion: The monolith diffusion-controlled bilayer tablets of metformin hydrochloride and gliclazide offer improved patient compliance and convenience with better postprandial hyperglycemic control with once-a-day dosing. The sustained release of the drug up to 24 h regulate antidiabetic activity round the clock with minimal side effects.

Experimental analysis of the influence of polymer solutions on performances and cavitation of small size pumps for professional appliances

Pumps used in professional appliances process a solution of water, soils residues and detergents. These affect vapor tension, viscosity and rheology of the solution, mainly due to the presence of surfactants and polymers. Only a few studies have been found on how these substances can influence pump performances. Therefore, an experimental analysis has been carried out with aqueous solutions of a detergent component, the Polyox WSR 301, in the concentration range of 100–7000 ppm, to evaluate their influence on pump performances and cavitation. Some properties of the solutions have been preliminary characterized with a rheometer. Then, each solution has been tested in a dedicated test rig, to compare the performance curves of a centrifugal pump used in professional warewashing machines with those obtained with pure water. A non-intrusive method, based on the investigation of high frequency vibrations and noise signals, has been developed to detect cavitation at its early stage of inception. It was observed that polymer mitigates cavitating pump vibrations, with a reduction of the acceleration to less than one g. The analysis has provided the data necessary for the successive development of a control strategy for pump operation in professional appliances.

SYNERGISTIC EFFECT OF POLYMER-POLYMER MIXTURES AS DRAG REDUCING AGENTS ON OIL-WATER FLOWS

The synergistic effect of natural and synthetic polymers as drag reducing agents in water phase during horizontal oil-water flows was studied in 12 mm internal diameter (ID) unplasticised polyvinylchloride (uPVC) pipe. Partially hydrolyzed polyacrylamide (HPAM; trade name as magnafloc 1011 or Separan), polyethylene oxide (PEO; trade name as Polyox WSR 310), Aloe Vera mucilage (AVM; as Aloe barbadensis miller), mixture of partially hydrolyzed polyacrylamide and Aloe Vera mucilage and polyethylene oxide and Aloe Vera mucilage (HPAM-AVM and PEO-AVM) were used. Mixture Reynolds number of 62923, master solution of 2000 ppm and 20000 ppm, and total concentration (TC) of 30 ppm and 400 ppm were investigated using diesel oil (ρ = 832 kg/m3, µ = 1.66 cP) and water (ρ = 1000 kg/m3, µ = 0.89 cP) as test fluids. The results show that the drag reduction (DR) of 65.39 and 69.23%, and 69.23 and 70.77% were obtained for HPAM-AVM and PEO-AVM mixtures respectively, at mixing ratios of 3:1 and 1:19, for 25% oil input fraction and water phase Reynolds number (Rew) of 47192. These values were found to be higher than the DR obtained by individual polymer alone at the same conditions. Drag reduction decreased with increase in the oil input fraction due to the decrease in the water phase Reynolds number. The result implies drag reduction efficiency can be enhanced by combining natural and synthetic polymers.

Preformulation Studies of Rapid Dissolving Films Containing Granisetron Hydrochloride

Rapid-dissolving solid drug dosage forms for application onto the oral cavity for the pediatric population seem to be very appropriate, especially in preterm and term infants. The delivery of drugs via the oral mucosa offers easy application, prevents drug degradation by gastrointestinal fluids, avoids first-pass metabolism and potentially improves bioavailability. Granisetron hydrochloride (GSH) drug is used as antiemetic agent. Proposed work comprise of preformulation studies of Granisetron hydrochloride. For that, physicochemical parameters were determined; like melting point of GSH was determined using melting point apparatus, Granisetron hydrochloride was scanned in the distilled water, Acid buffer, pH 1.2 and Phosphate buffer, pH 6.8. The IR spectrum of pure drug (GSH), Pullulan, METHO K3P, METHO E3P, METHO E15P and POLYOX WSR N10 were recorded in potassium bromide using Shimadzu FTIR – 8400S(CE). Solubility of Granisetron hydrochloride was determined using shake flask method. Standard Plot of Granisetron hydrochloride in distilled water, Acid buffer, pH 1.2 and Phosphate buffer, pH 6.8 were taken, all the parameter obtained were satisfactory, which will be used further for formulation of rapid dissolving film. Keywords: Rapid dissolving film, Granisetron hydrochloride (GSH), Preformulation.

Gastroretentive Floating-Bioadhesive Drug Delivery System for Rebamipide: Design, In vitro and In vivo Evaluation

Rebamipide is an amino acid analog of 2-(1H)-quinolinone used in the treatment of peptic ulcer. Here we sought to formulate and evaluate gastroretentive floating-bioadhesive tablets of rebamipide to increase the gastric residence time and further compare their pharmacokinetics with conventional immediate release tablets. Floating-bioadhesive tablets of rebamipide were prepared with combination of Polyox WSR 303 and CP 971P/HPMC K4M and Sodium CMC by direct compression method. The prepared formulations were evaluated for hardness, thickness, weight variation, friability, drug content, in vitro buoyancy and drug release. The optimized formulation (RBF12) floated with a lag time of 28.3 ± 3.2 sec, duration of floating 12 h and released about 99.91 ± 1.84% of drug in 12 h, and then followed non-Fickian diffusion release mechanism with n value of 0.635. The RBF12 tablets with BaSO4 remained in stomach for 5.13 ± 0.64 h (n=3) in radiological studies. The formulation, RBF12 exhibited maximum bioadhesive strength (1.346 ± 0.110 N) than other formulations. The bioavailability studies were carried out for the optimized formulation (RBF12) and compared with that of reference IR tablets “Rebagen” in nine healthy human volunteers. Based on in vivo performance significant difference was observed between Cmax, tmax, t1/2, AUC0–∞, and MRT of RBF12 and IR tablets. The increase in relative bioavailability of RBF12 was 1.7-fold when compared to reference IR tablets. The increased relative oral bioavailability may be due to the floating-bioadhesive mechanism of dosage form, which is desirable for drugs absorbed from the upper part of gastrointestinal tract.

DEVELOPMENT AND IN VITRO–IN VIVO EVALUATION OF GASTRORETENTIVE FLOATING TABLETS OF AN ANTIRETROVIRAL AGENT RITONAVIR

Objective: The present research work concerns the development of the extended release of Ritonavir floating matrix tablets, designed to prolong the gastric residence time, increase the drug bioavailability, and diminish the side effects of irritating drugs.&#x0D; Methods: The floating tablets of Ritonavir were prepared by direct compression method using different grades of hydroxypropyl methylcellulose (HPMC), crospovidone, Polyox WSR 303, and sodium bicarbonate, as gas generating agent. Evaluation parameters and in vivo radiographic studies were conducted in suitable model.&#x0D; Results: Among all formulations, F21 was chosen as optimized formulation based on evaluation parameters such as floating lag time (33 s), total floating time (&gt;24 h), and in vitro dissolution studies. From in vitro dissolution studies, the optimized formulation F21 and marketed product were shown 98.67% and 91.46±5.02% of drug release, respectively. The main appliance of medication discharge follows zero-order kinetics and non- Fickian transport by coupled diffusion and erosion. In vivo experiments maintained the potentials in extending the gastric residence time in the fasted state in beagle dogs. The mean gastric residence time of the optimized formulation found to be 330 min±40 in the stomach, where longer gastric residence time is an important condition for prolonged or controlled drug release and also for enhanced bioavailability.&#x0D; Conclusion: From in vitro and in vivo radiographic studies, Ritonavir floating tablets estimated to provide novel choice for harmless, inexpensive, and extended release for the effective management of AIDS.

Formulation and Pharmacokinetic Evaluation of Ritonavir Floating Tablets in the Management of AIDS

In the current study, gastro-retentive tablets of Ritonavir was developed to increase its oral bioavailability using hydrophilic polymers HPMC K 4M, K 15M, and K 100M as release retarding agents. Polyox WSR 303 was chosen as resin, sodium bicarbonate was used as effervescent agents. The tablets were prepared by direct compression method and FTIR studies revealed that there is no interaction between the drug and polymers used for the formulation. Among all the formulations F21 containing HPMC K 100M, Crospovidone, Polyox WSR 303 and sodium bicarbonate, as gas generating agent was choosen as optimized formulation based on the evaluation parameters, floating lag time (33 sec) and total floating time (&gt;24 h) and in vitro dissolution studies. From in vitro dissolution studies, the optimized formulation F21 and marketed product was shown 98.67% and 95.09 ± 5.01% of drug release respectively. From in vivo bioavailability studies, after oral administration of floating tablet containing 100 mg Ritonavir, the Cmax, Tmax, and AUC0–∞ of optimized gastroretentive formulation were found to be 30.11 ± 1.16μg/mL, 8.00±1.23 h and 173 ± 26.34μg*h/ml, respectively. Cmax and AUC values of optimized formulation were found to be significantly higher than of marketed product, where longer gastric residence time is an important condition for prolonged or controlled drug release and also for improved bioavailability.

GASTRO-FLOATING TABLETS OF REPAGLINIDE: PREPARATION AND IN VIVO EVALUATION

Objective: Current research concerns the expansion of repaglinide matrix floating tablets, which are designed to prolong the gastric residence time, increase the drug bioavailability, and diminish the side effects.Methods: Different formulations of repaglinide floating tablets were prepared with different grades of hydroxypropyl methylcellulose (HPMC) and other agents. Evaluation parameters and in vivo bioavailability studies were conducted in the suitable model.Results: Among all the formulations, F21 containing HPMC K1500 PH PRM, Polyox WSR 303, and sodium bicarbonate, as gas generating agent was selected as optimized formulation based on physicochemical properties, floating lag time (36 s), and total floating time (&gt;24 h). From in vitro dissolution studies, the optimized formulation F21 showed drug release of 98.92±5.19% within 24 h whereas 95.09±5.01% of the drug was released from the marketed product within 1 h.Conclusion: From in vitro and in vivo bioavailability studies repaglinide floating tablets expected to give a new choice for safe, economical, and increased bioavailability for effective management of diabetes mellitus.

DEVELOPMENT AND IN VIVO EVALUATION OF NELFINAVIR EXTENDED RELEASE TRILAYER MATRIX TABLETS IN THE MANAGEMENT OF AIDS

The purpose of this investigation was to design and develop trilayer matrix tablets of Nelfinavir prepared by direct compression method and consisted of middle active layer with different grades of hydroxypropyl methylcellulose (HPMC), PVK K 30 and MCC. Barrier layers are prepared with Polyox WSR 303, Xanthan gum, microcrystalline cellulose and magnesium stearate. Based on the evaluation parameters, drug dissolution profile and release drug kinetics DF8 was found to be optimized formulation. The developed drug delivery system provided prolonged drug release rates over a period of 24 h. The release profile of the optimized formulation (DF8) was described by the Zero-order and best fitted to Higuchi model. From in vivo bioavailability studies the extended release of Nelfinavir from trilayer matrix tablets also provides for higher plasma drug content and improved bioavailability. The results indicate that the approach used could lead to a successful development of low biological half life Nelfinavir with controlled drug release in the effective management of AIDS.