Formulation Of Bilayer Tablets Research Articles

Formulation and Evaluation of Immediate Release Bilayer Tablets of Telmisartan and Hydrochlorothiazide

The main goal of this study was to develop a stable formulation of antihypertensive drugs telmisartan and hydrochlorothiazide as an immediate-release bilayer tablet and to evaluate the dissolution profile in comparison with a reference product. The formulation development work was initiated with wet granulation. Telmisartan was converted to its sodium salt by dissolving in aqueous solution of sodium hydroxide to improve solubility and drug release. Lactose monohydrate and microcrystalline cellulose were used as diluents. Starch paste is prepared in purified water and was used as the binder. Sodium starch glycolate is added as a disintegrating agent. Magnesium stearate was used as the lubricant. The prepared granules were compressed into a double-layer compression machine. The tablets thus formulated with higher proportion of sodium starch glycolate showed satisfactory physical parameters, and it was found to be stable and in vitro release studies are showed that formulation (F-T5H5) was 101.11% and 99.89% respectively. The formulation T5H5 is further selected and compared with the release profile of the innovator product, and was found to be similar (f2 factor) to that of the marketed product. The results suggest the feasibility of developing bilayer tablets consisting of telmisartan and hydrochlorothiazide for the convenience of patients with hypertension.

Development and Evaluation of Controlled-Release Bilayer Tablets Containing Microencapsulated Tramadol and Acetaminophen

Purpose: To develop and characterize bilayer tablet formulations of tramadol HCl (TmH) and acetaminophen (AAP) microparticles.Methods: Coacervation via temperature change was the encapsulated method used for the preparation of the microparticles, with ethyl cellulose (EC) of medium viscosity as the polymer for extending drugrelease. The microparticles of the two drugs were prepared separately and then compressed into bilayer tablets. The physicochemical compatibility and stability of the tablets were determined by Fouriertransform infrared spectroscopy (FTIR), x-ray diffractometry (XRD), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) while their mechanism and pattern of drug release wereassessed by applying Higuchi, Zero order, First order and Korsmeyer-Peppas kinetic models. Bilayer tablets were subjected to accelerated stability studies for three months. Results: FTIR, XRD, DSC and TGA data for the formulations indicate good compatibility and stability.Furthermore, accelerated stability studies confirmed the stability of the formulations. Controlled drug release from the microparticles and bilayer tablets was observed for 8 h and 12 h, respectively. TheHiguchi model produced the best fit, with regard to release profile, for both drugs, with correlation coefficient (R2) of 0.966 and 0.960 for AAP and TmH, respectively. Conclusion: Microencapsulated TmH and AAP can be developed into suitable bilayer tablets that are stable and capable of releasing the drugs over 12 h.Keywords: Acetaminophen; Tramadol; Ethyl cellulose; Microparticles; Bilayer tablets; Kinetic models

RP-LC Simultaneous Determination of Nebivolol Hydrochloride and Amlodipine Besilate in Bi-Layer Tablets

A simple and rapid LC method was developed and validated for simultaneous estimation of nebivolol and amlodipine in a bi-layer tablet formulation. Efficient chromatographic separation was achieved on (USP L10) Hypersil BDS cyano, 5 μm, 250 mm × 4.6 mm column with simple mobile phase composition delivered in isocratic mode. The method had requisite accuracy, selectivity, sensitivity, robustness and precision to assay nebivolol and amlodipine in pharmaceutical dosage form. Degradation products resulting from the stress studies did not interfere with the detection of nebivolol and amlodipine, these peaks remained pure and thus proved to be stability indicating. The mass balance of the stressed sample was in the range 99.0–100.2% for amlodipine and 99.3–100.3% for nebivolol.

Formulation and evaluation of bi-layer tablet of metoclopramide hydrochloride and ibuprofen.

The aim of this study was to prepare bi-layer tablet of Metoclopramide Hydrochloride (MTH) and Ibuprofen (IB) for the effective treatment of migraine. MTH and IB were formulated as immediate and sustained release layer respectively. MTH was formulated as immediate release layer by using various disintegrants like Ac-Di-Sol, Polyplasdone XL, Explotab, Agar and Gellan Gum. Treated form of gellan gum and agar was prepared and compared for their disintegrant efficiency with other disintegrants. IB was formulated as sustained release layer using hydrophilic matrix (hydroxypropylmethylcellulose [HPMC K(4)M]). The effect of concentration of hydrophilic matrix (HPMC K(4)M), binder (polyvinylpyrollidone [PVP K(30)]) and buffer (sodium bicarbonate) on IB release was studied. The dissolution study of sustained release layer showed that an increasing amount of HPMC or PVP K(30) results in reduced IB release. The inclusion of buffer (sodium bicarbonate) enhanced the release of IB from sustained release layer. The rational for formulation of bi-layer tablet of these two drugs in combination was (1) MTH increases the absorption of acidic non-steroidal anti-inflammatory drug (NSAID) by increasing gastric motility. So sequential release of MTH (as immediate release) and IB (as sustained release) was suitable for treatment of migraine. (2) MTH was degraded when prolonged contact with acidic NSAID. Bi-layer tablet was suitable for preventing direct contact of these two drugs and thus to maximize the efficacy of combination of two drugs for migraine.

A phase II/III clinical trial investigating the treatment of insomnia with a bilayer tablet formulation of adipiplon has been suspended

A phase II/III clinical trial investigating the treatment of insomnia with a bilayer tablet formulation of adipiplon has been suspended

Stability of amlodipine besylate and atenolol in multi-component tablets of mono-layer and bi-layer types

Multi-drug tablets of amlodipine besylate and atenolol were prepared as either mono-layer (mixed matrix) or bilayer tablets containing each drug in a separate layer by using similar excipients and processing. Each tablet batch was packed in strip and blister packs and kept under accelerated temperature and humidity conditions. The stability of two tablet and packaging types was compared by HPLC analysis after 0, 1, 3 and 4.5 months and expressed as the content of intact amlodipine and atenolol. The content of atenolol did not decline regardless of tablet and packaging type. Amlodipine content in bi-layer tablets decreased to about 95 and 88% when packed in strips and blisters, respectively. When prepared as mono-layer tablets, the content decreased to 72 and 32%, respectively.The study revealed that the bi-layer tablet formulation was more stable than the mono-layer type. Further, the stability was increased when the tablets were packed in aluminium strips as compared to PVC blisters.

Mucoadhesive Delivery Systems. II. Formulation and In‐Vitro/In‐Vivo Evaluation of Buccal Mucoadhesive Tablets Containing Water‐Soluble Drugs

From the previous work (Part I), mucoadhesive formulae containing 5% CP/65% HPMC/30% lactose and 2% PC/68% HPMC/30% mannitol as well as formulae based on sodium carboxymethyl cellulose (SCMC) were selected. Medicated tablets were prepared using diltiazem hydrochloride (DZ) and metclopramide hydrochloride (MP) in two different doses (30 and 60 mg). The effect of drug and dose on the mucoadhesive properties and in‐vitro drug release was evaluated. All formulae produced extended drug release (over 8 to 12 h). Polyacrylic acid based matrices (PAA) showed Fickian's diffusion release pattern for both drugs. SCMC ensured zero‐order release for DZ, which deviated to anomalous behavior in case of MP. Doubling the dose significantly reduced the bioadhesion strength (p < 0.05) with a slight improvement in drug release rate. The formulation of bilayer tablets containing drug‐free layer and medicated layer enhanced the drug release without affecting the bioadhesive performance. The bilayer tablet formulated with 2% PC/68% HPMC/30% mannitol (PC2) was selected for studying the in‐vivo metoclopramide release in four healthy volunteers. The tablet ensured controlled drug release for 12 h, in addition, good correlation (r = 0.9398) was observed between in‐vitro and in‐vivo data. The effect of ageing on selected formulae containing DZ and MP, respectively, was studied. Storage at 40°C and 75% relative humidity for 6 months didn't influence the mucoadhesive performance, however, an enhanced released rate was observed.

Studies of Floating Dosage Forms of Furosemide: In Vitro and In Vivo Evaluations of Bilayer Tablet Formulations

For the purpose of enhancement the bioavailability of furosemide (FR), a floating dosage form with controlled release of FR was designed in this study. Because of the lower solubility of active material in the gastric medium, it was first enhanced by preparing an inclusion complex of FR with beta-cyclodextrin (β-CD) in a 1:1 proportion using the kneading method. Following the design of dosage form, bilayer floating tablets were prepared. After dissolution rate studies were performed using the continuous flow-through cell method, the formulation that provided delivery of active material near the target profile was given to six healthy male volunteer subjects, and in vivo tests were performed. It was determined by radiographs that floating tablets prepared by adding BaSO4 stayed in the stomach for 6 hr. Further, values of the area under the plasma concentration-time curve (AUC) obtained with the floating dosage form were about 1.8 times those of the conventional FR tablet in blood analyses; maximum and minimum plasma concentrations were also found to be between the desired limits. In urine analyses, the peak diuretic effect seen in classical preparations was decreased and prolonged in floating dosage forms. Also, a considerably significant correlation was detected between in vivo results and in vitro data of the dissolution rate, and it was concluded that the modified continuous flow-through cell method is usable for in vitro dissolution rate tests of floating dosage forms.

Evaluation of Bilayer Tablet Machines—A Case Study

AbstractFour bilayer tablet compression machines were evaluated for their suitability for compression of a specific bilayer tablet formulation. Tablet machines evaluated were: Manesty (Model No. BB4), Manesty (Model No. Rotappress), Fette (Model No. P3102) and Kilian (Model No. 51AST-ZS) tablet presses. The tablet delamination tendency was the primary acceptance criteria for the evaluation of tablet press performance. The compression force on layer I was found to be the major factor influencing tablet delamination. It was found that the Kilian press was best suited for the compression of the model bilayer tablet formulation. The Kilian press is equipped with a special sampling device for layer I which allows additional compression force to be applied on layer I only at the time of weight sampling. The sampling device then returns to the original set points after sampling is completed. This feature maintains the compression force on layer I to a minimum during routine compression. Data indicated that the c...