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1.
This article reports the exploitation of novel hydrophilic excipient, that is, mucilage from Hibiscus rosasinensis Linn, for the development of sustained release tablet. Swelling ratio and flow properties analyses of dried mucilage powder were carried out. A 3(2) full factorial design was used. In factorial design, amounts of dried mucilage and dibasic calcium phosphate (DCP) were taken as independent factors and percentage drug release in 60 and 300 min and time for 80% drug release as dependent variables. Matrix tablet containing dried mucilage and diclofenac sodium (DS) was prepared through direct compression techniques. DS tablets were evaluated for hardness, friability, weight variation, in vitro drug release and water uptake, and mass loss study. The dried mucilage powder shows superior swelling capacity and excellent flow properties. Prepared tablets have acceptable hardness, friability, and uniformity in weight. It was found that batch HD8 fulfills all selected criteria. Drug release kinetics from these formulations corresponded best to the zero-order kinetics. Water uptake was independent whereas mass loss was dependent on agitation speed. The concept of similarity factor (f(2)) was used to prove similarity of dissolution profile in distilled water and phosphate buffer and was found to be 90.68. It was concluded that mucilage can be used as release-retarding agent for 12 h when the drug-mucilage ratio was 1:1.5. So, matrix tablet containing dried mucilage is most suitable for sustained release of DS.  相似文献   

2.
Context: Conventional sustained dosage form of ranitidine hydrochloride (HCl) does not prevent frequent administration due to its degradation in colonic media and limited absorption in the upper part of GIT.

Objectives: Ranitidine HCl floating tablet was formulated with sublimation method to overcome the stated problem.

Methods: Compatibility study for screening potential excipients was carried out using Fourier transform infrared spectroscopy (FT-IR) and differential scanning chromatography (DSC). Selected excipients were further evaluated for optimizing the formulation. Preliminary screening of binder, polymer and sublimating material was based on hardness and drug release, drug release with release kinetics and floating lag time with total floatation time, respectively. Selected excipients were subjected to 32 factorial design with polymer and sublimating material as independent factors. Matrix tablets were obtained by using 16/32” flat-faced beveled edges punches followed by sublimation.

Results: FT-IR and DSC indicated no significant incompatibility with selected excipients. Klucel-LF, POLYOX WSR N 60?K and l-menthol were selected as binder, polymer and sublimating material, respectively, for factorial design batches after preliminary screening. From the factorial design batches, optimum concentration to release the drug within 12?h was found to be 420?mg of POLYOX and 40?mg of l-menthol. Stability studies indicated the formulation as stable.

Conclusion: Ranitidine HCl matrix floating tablets were formulated to release 90% of drug in stomach within 12?h. Hence, release of the drug could be sustained within narrow absorption site. Moreover, the dosage form was found to be floating within a fraction of second independent of the pH of media ensuring a robust formulation.  相似文献   

3.
Objective: The purpose of this work was to develop and evaluate buccoadhesive tablets of timolol maleate (TM) due to its potential to circumvent the first-pass metabolism and to improve its bioavailability.

Methods: The tablets were prepared by direct compression using two release modifying polymers, Carbopol 974P (Cp-974p) and sodium alginate (SA). A 32 full factorial design was employed to study the effect of independent variables, Cp-974p and SA, in various proportions in percent w/w, which influences the in vitro drug release and bioadhesive strengths. Physicochemical properties of the drug were evaluated by ultraviolet, Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC) and powder X-ray diffraction (P-XRD). Tablets were evaluated for hardness, thickness, weight variation, drug content, surface pH, swelling index, bioadhesive force and in vitro drug release.

Results: The FTIR and DSC studies showed no evidence of interactions between drug, polymers and excipients. The P-XRD study revealed that crystallinity of TM remain unchanged in optimized formulation tablet. Formulation F9 achieves an in vitro drug release of 98.967%?±?0.28 at 8?h and a bioadhesive force of 0.088 N?±?0.01211.

Conclusion: We successfully developed buccal tablet formulations of TM and describe a non-Fickian-type anomalous transport as the release mechanism.  相似文献   

4.
A sustained-release (SR) formulation of phenobarbital (PB) microcapsule tablet was prepared using low molecular weight (MW) DL- and high MW L-poly(lactic acid) (PLA) polymer. Microencapsulation of PB showed a unimodal size distribution (375 to 550 microns) of the microcapsules with high loading capacity (> 84%). Drug release from the microcapsule was influenced by the polymer ratios and increased with an increase in L-PLA amount. Microcapsules and physical mixtures of PB and the PLA were directly compressed independently to form microcapsule and matrix tablets, respectively. Drug release from the microcapsule tablets was significantly lowered (p < .001) compared to matrix tablets or free microcapsule (free microcapsule > matrices > microcapsule tablets). We also investigated the effect of tablet adjuvants, compression pressures, and microcapsule loading on the tablet performance in terms of friability, hardness, porosity, tensile strength, and the release kinetics of PB. The drug release rate increased with increasing compression pressure in the case of Emcompress or lactose, but not Avicel. The drug release rate was three- to fivefold increased with sodium starch glycolate compared to tablets without a disintegrant. With an increase in microcapsule loading, a decrease in the drug release rate was observed; however, the tablet performance remained satisfactory. The morphology of the microcapsules was monitored microscopically after the dissolution and the disintegration of tablets. The drug release accelerated with compression pressures and microcapsule loading from the tablets due to mechanical destruction of the microcapsule wall, which was more clearly seen after disintegration and dissolution of the tablets. Our data suggest that the PLA microcapsule can be tableted to make a SR product without significantly affecting its release kinetics.  相似文献   

5.
The dry binding activity of copolyvidone (Kollidon® VA 64), povidone (Kollidon® 30), microcrystalline cellulose (Avicel® PH-101), hydroxypropylmethylcellulose (HPMC) 2910 (Pharmacoat® 606), and maltodextrin (Maldex® 18) was investigated using a variety of formulations and methods. The effect of the dry binders in direct tableting and compaction was studied using a dicalcium phosphate formulation (water-insoluble ingredients) and a vitamin C formulation (water-soluble ingredients) applying three compression forces. The binder content was varied between 5% and 15% in both formulations, and the tablet properties were determined. All the tablets showed an improvement in mechanical properties (hardness, friability) with increasing dry binder concentration, with Kollidon VA 64 showing by far the greatest binding efficacy. A significant influence (prolongation) on drug release was observed only with HPMC 2910. The drying binding properties were analyzed for correlations with various powder and material properties. Especially, particle size, surface/surface structure, and plasticity were found to influence binding activity. The ideal dry binder should have small particles, high plasticity, and a large surface area.  相似文献   

6.
Abstract

The objective of this study was to evaluate powdered lipids as both granulating agents and retardants in formulated sustained-release acetaminophen tablets. Castor Wax or Durkee 07 powders were premixed with acetaminophen and granulated with boiling water. After cooling, the mass was screened to obtain a 10/20 mesh fraction which was used for tablet production and evaluation. Friability, hardness, dissolution and compression profiles were monitored. As lipid content increased from 5-15% w/w, friability and hardness also increased. Dissolution showed an inverse relationship between level of lipid and release rate. Compression profiles demonstrated good transmission when Castor Wax was employed. This study demonstrated that a high milligram potency tablet could be fabricated with low levels of lipid, to retard drug release, without significantly increasing tablet weight and size.  相似文献   

7.
Context: Hydrophilic and hydrophobic polymer-based nicorandil (10 mg)-loaded peroral tablets were prepared using the wet granulation technique. The influence of varying amounts of hydroxypropyl methylcellulose (HPMC) (30–50 mg), ethylcellulose (2–4 mg), microcrystalline cellulose (5–20 mg) and Aerosil® (5–12 mg) in conjunction with the constant amounts (3 mg) of glidant and lubricant (magnesium stearate and talc) on the in vitro performances of the tablets (hardness, friability, weight variation, thickness uniformity, drug content, and drug release behavior) were investigated. Objective: The objectives of this study were (i) to select a nicorandil-loaded peroral tablet that matched the in vitro dissolution profile of once-daily commercial sustained-release tablet, and (ii) to compare the in vivo sustaining/controlling efficacy of the selected peroral tablet with that of its commercial counterparts. Results and Discussion: Because the nicorandil (10 mg)-loaded tablet prepared based on F-IX composition (50 mg HPMC, 4 mg ethylcellulose, 10 mg MCC and 3 mg glidant and lubricant) showed a release profile comparable to that of the Nikoran® OD SR tablet release profile, the tablet with this composition was considered to be the optimized/selected formulation and, therefore, was subjected to stability study and in vivo study in rabbits. Despite of the higher Cmax and AUC values obtained with the optimized tablet, there was no sign of difference between the optimized- and Nikoran® OD SR- tablets following a single-dose crossover oral administration into rabbit. Conclusion: The optimized tablet could be used as an alternative to the commercial once-daily tablet.  相似文献   

8.
Context: The bitter taste of drug is masked by the exchange of ionized drugs with counter ions of ion exchange resin, forming “resinate”. Cyclodextrin reduces the unpleasant taste and enhances the drug solubility by encapsulating drug molecules into its central cavity.

Objective: Oral disintegrating tablets (ODTs) using the combination of ion exchange resin and cyclodextrin was developed, to mask the bitter taste and enhance drug dissolution.

Methods: Meloxicam (MX) was selected as a model drug. Formulations containing various forms of MX (free drug, MX-loaded resin or resinate, complexes of MX and 2-hydroxypropyl-β-cyclodextrin (HPβCD) or MX/HPβCD complexes, and a mixture of resinate and MX/HPβCD complexes) were made by direct compression. The ODTs were evaluated for weight variation, thickness, diameter, hardness, friability, disintegration time, wetting time, MX content, MX release, degree of bitter taste and stability.

Results and discussion: The tablet hardness was ~3?kg/in2, and the friability was <1%. Tablets formulated with resinate and the mixture of resinate and MX/HPβCD complexes disintegrated rapidly within 60?s, which is the acceptable limit for ODTs. These results were corresponded to the in vivo disintegration and wetting times. However, only tablets containing the mixture of resinate and MX/HPβCD complexes provided complete MX dissolution and successfully masked the bitter taste. In addition, this tablet was stable at least 6 months.

Conclusions: The combination of ion exchange resin and cyclodextrin could be used in ODTs to mask the bitter taste and enhance the dissolution of drugs that are weakly soluble in water.  相似文献   

9.
Objective: Venlafaxine is freely soluble In water and administered orally as hydrochloride salt In two to three divided doses. In the present investigation different release retarding matrices have been evaluated for sustained release of venlafaxine hydrochloride (VH) from the formulated tablets.

Materials and methods: Sustained release matrix tablets were formulated using different hydrophilic, hydrophobic and waxy materials as matrix formers. Tableting was done by pre-compression, direct compression and hot melt granulation depending on the type of matrix material used and evaluated for different tests. The formulated tablets were compared with commercial venlafaxine products. In vitro drug dissolution profiles were fitted In different mathematical models to elucidate the release mechanism.

Results: Dissolution data showed that commercial formulations Venlor XR® and Venfax PR® released the entire drug withIn 8?h where as the formulated tablets with hydroxypropylmethylcellulose (HPMC) and cetyl alcohol as matrix formers provided sustained release of drug for 14–15?h. The release was found to follow Hixson Crowel and Higuchi kinetics for HPMC and cetyl alcohol tablets, respectively.

Conclusion: The developed matrix tablet formulations with HPMC and cetyl alcohol provided sustained release profiles for prolonged periods than commercial formulations.  相似文献   

10.
Abstract

Cissus root gum was processed and evaluated as a binder in lactose-based tablets each containing 100 mg of sodium salicylate as the active ingredient. Acacia binder was used as basis for comparison. Tablet hardness, friability, disintegration time and dissolution rate were the parameters investigated. The cissus gum gave hard and non-friable tablets at 1 - 3% w/w concentration of the tablet formula. Tablets containing above 2% w/w of the cissus gum gave high disintegration time values and the pattern of dissolution of the incorporated drug suggests that the gum may be useful in prolonged release tablet formulations. No significant changes in the tablet properties was observed after storage at 30°C for 16 weeks.  相似文献   

11.
Abstract

The properties of tablets prepared from different size fractions of chloroquine phosphate granules using different lubricants were evaluated. Lubricants used were magnesium stearate, stearic acid and talc, tablet properties studied include weight variation, crushing strength, friability and disintegration time

The effects obtained were largely dependent on the type and concentration of lubricant. Generally, as granule size increased, tablets were found to show increased weight variation, decreased hardness and increased friability. With tablets containing talc as lubricant, disintegration time was shown to decrease with increase in granule size.

There appears to be an optimum lubricant concentration for the compression of different granule size fractions.  相似文献   

12.
ABSTRACT

This study investigates the effects of three factors: (1) use of a mixture of two different grades of hydroxypropyl methylcellulose (HPMC), (2) apparent viscosity, and (3) tablet hardness on drug release profiles of extended-release matrix tablets. The lot-to-lot apparent viscosity difference of HPMC K15M on in vitro dissolution was also investigated. Four test formulations were made, each containing 10% of a very water-soluble active pharmaceutical ingredient (API), 32% HPMC K15M, or a mixture of HPMC K100LV and HPMC K100M, 56% diluents, and 2% lubricants. Each formulation was made at two hardness levels. A 23 full factorial design was used to study various combinations of the three factors using eight experiments conducted in a randomized order. Dissolution studies were performed in USP apparatus I. The values of t50% (time in which 50% drug is released) and tlag (lag time, the time taken by the matrix tablet edges to get hydrated and achieve a state of quasi-equilibrium before erosion and the advance of solvent front through the matrix occur) were calculated from each dissolution profile. The similarity factor (f2) was also calculated for each dissolution profile against the target dissolution profile. A simple Higuchi-type equation was used to analyze the drug release profiles. Statistical analysis using analysis of variance (ANOVA) and similarity factor (f2) values calculated from the data indicated no significant difference among the t50% values and dissolution profiles respectively for all formulations. Within the 3.3–6 kp hardness range investigated, dissolution rates were found to be independent of tablet hardness for all the formulations. Although significantly shorter lag times were observed for the tablets formulated with low- and high-viscosity HPMC mixtures in comparison to those containing a single grade of HPMC, this change had no significant impact on the overall dissolution profiles indicated by the similarity factor f2 values. From this study it can be concluded that lot-to-lot variability in apparent viscosity of HPMC should not be a concern in achieving similar dissolution profiles. Also, results indicated that within the viscosity range studied (12,000–19,500 cps) an HPMC mixture of two viscosity grades can be substituted for another HPMC grade if the apparent viscosity is comparable. Also, the drug release is diffusion-controlled and depends mostly on the viscosity of the gel layer formed.  相似文献   

13.
Pyridostigmine bromide (PB), a highly hygroscopic drug was selected as the model drug. A sustained-release (SR) tablet prepared by direct compression of wet-extruded and spheronized core pellets with HPMC excipients and exhibited a zero-order sustained release (SR) profile. The 23 full factorial design was utilized to search an optimal SR tablet formulation. This optimal formulation was followed zero-order mechanism and had specific release rate at different time intervals (released % of 1, 6, and 12 hr were 15.84, 58.56, and 93.10%). The results of moisture absorption by Karl Fischer meter showed the optimum SR tablet could improve the hygroscopic defect of the pure drug (PB). In the in vivo study, the results of the bioavailability data showed the Tmax was prolonged (from 0.65 ± 0.082 hr to 4.83 ± 1.60 hr) and AUC0–t (from 734.88 ± 230.68 ng/ml.hr to 1153.34 ± 488.08 ng/ml.hr) and was increased respectively for optimum PB-SR tablets when compared with commercial immediate release (IR) tablets. Furthermore, the percentages of in vitro dissolution and in vivo absorption in the rabbits have good correlation. We believe that PB-SR tablets designed in our study would improve defects of PB, decrease the frequency of administration and enhance the retention period of drug efficacy in vivo for personnel exposed to contamination situations in war or terrorist attacks in the future.  相似文献   

14.
Background: Oxycellulose (OC) is biodegradable and bioabsorbable cellulose derivative used in medicine to support hemostasis and tissue healing. Recently, its antimicrobial and immunomodulating properties, as well as its potential in modern therapeutic systems as release modifying excipient, drug carrier, and/or mucoadhesive polymer, are widely discussed. Method: To study its last-mentioned characteristics, directly compressed tablets containing 5 mg of cetylpyridinium chloride (CPC) as a model drug and 90 mg of mucoadhesive polymer [oxycellulose sodium (NaOC) alone or in a combination with one of five widely used mucoadhesive polymers] were prepared to ensure 8 hours prolonged release of CPC. Physicochemical and mucoadhesive properties of prepared tablets were evaluated. Results: Based on obtained results, tablets containing OC in combination with hydroxypropylmethylcellulose (Methocel® K100LV) or carboxymethylcellulose sodium showed the best quality parameters (friability < 0.04%, tablet thickness < 2.17 mm, tablet hardness > 85 N, residence time > 256 minutes, mucoadhesive strength > 3.45 mN/mm) and dissolution profiles (more than 81% of CPC released within 8 hours). Conclusion: NaOC embodies excellent compressing, mechanical, and mucoadhesive properties; however, formulation with higher content of NaOC only showed shorter adhesion time (107 ± 7 minutes) and faster drug release (93.66% of CPC released within 2 hours), because of its good solubility in aqueous media.  相似文献   

15.
Context: Continuous processing is becoming popular in the pharmaceutical industry for its cost and quality advantages.

Objective: This study evaluated the mechanical properties, uniformity of dosage units and drug release from the tablets prepared by continuous direct compression process.

Materials and methods: The tablet formulations consisted of acetaminophen (3–30% (w/w)) pre-blended with 0.25% (w/w) colloidal silicon dioxide, microcrystalline cellulose (69–96% (w/w)) and magnesium stearate (1% (w/w)). The continuous tableting line consisted of three loss-in-weight feeders and a convective continuous mixer and a rotary tablet press. The process continued for 8?min and steady state was reached within 5?min. The effects of acetaminophen content, impeller rotation rate (39–254?rpm) and total feed rate (15 and 20?kg/h) on tablet properties were examined.

Results and discussion: All the tablets complied with the friability requirements of European Pharmacopoeia and rapidly released acetaminophen. However, the relative standard deviation of acetaminophen content (10% (w/w)) increased with an increase in impeller rotation rate at a constant total feed rate (20?kg/h). A compression force of 12?kN tended to result in greater tablet hardness and subsequently a slower initial acetaminophen release from tablets when compared with those made with the compression force of about 8?kN.

Conclusions: In conclusion, tablets could be successfully prepared by a continuous direct compression process and process conditions affected to some extent tablet properties.  相似文献   

16.
Dyphylline tablets were prepared by direct compression of mixtures of the drug, emcompress and different ratios of hydroxypropyl methylcellulose (HPMC) or cellulose acetate phthalate (CAP). Physical properties of the prepared tablets and the drug release in 0.1 N HC1 and phosphate buffer, pH 7.4 were investigated.

All tablets were found to satisfy the USP requirements regarding content, weight uniformity and friability. Hardness was greatly enhanced and thickness was slightly increased by increasing the polymer ratio in tablet formulations. Disintegration time of the dyphylline tablets was delayed by the presence of either HPMC or CAP and there was a direct relationship between the polymer ratio and the disintegration time. Considerable retardation in the rate and extent of drug release from the prepared tablets in both dissolution liquids was observed. As the polymer ratio increased in the tablet formulations, the drug release was significantly inhibited.  相似文献   

17.
The aim of this study was to develop a high-dose tablet formulation of the poorly soluble carbamazepine (CBZ) with sufficient tablet hardness and immediate drug release. A further aim was to investigate the influence of various commercial CBZ raw materials on the optimized tablet formulation.

Materials and methods: Hydroxypropyl cellulose (HPC-SL) was selected as a dry binder and crospovidone (CrosPVP) as a superdisintegrant. A direct compacted tablet formulation of 70% CBZ was optimized by a 32 full factorial design with two input variables, HPC (0–10%) and CrosPVP (0–5%). Response variables included disintegration time, amount of drug released at 15 and 60?min, and tablet hardness, all analyzed according to USP 31.

Results and discussion: Increasing HPC-SL together with CrosPVP not only increased tablet hardness but also reduced disintegration time. Optimal condition was achieved in the range of 5–9% HPC and 3–5% CrosPVP, where tablet properties were at least 70 N tablet hardness, less than 1?min disintegration, and within the USP requirements for drug release. Testing the optimized formulation with four different commercial CBZ samples, their variability was still observed. Nonetheless, all formulations conformed to the USP specifications.

Conclusions: With the excipients CrosPVP and HPC-SL an immediate release tablet formulation was successfully formulated for high-dose CBZ of various commercial sources.  相似文献   

18.
A quality-by-design approach was adopted to develop telmisartan potassium (TP) tablets, which were bioequivalent with the commercially available Micardis® (telmisartan free base) tablets. The dissolution pattern and impurity profile of TP tablets differed from those of Micardis® tablets because telmisartan free base is poorly soluble in water. After identifying the quality target product profile and critical quality attributes (CQAs), drug dissolution, and impurities were predicted to be risky CQAs. To determine the exact range and cause of risks, we used the risk assessment (RA) tools, preliminary hazard analysis and failure mode and effect analysis to determine the parameters affecting drug dissolution, impurities, and formulation. The range of the design space was optimized using the face-centered central composite design among the design of experiment (DOE) methods. The binder, disintegrant, and kneading time in the wet granulation were identified as X values affecting Y values (disintegration, hardness, friability, dissolution, and impurities). After determining the design space with the desired Y values, the TP tablets were formulated and their dissolution pattern was compared with that of the reference tablet. The selected TP tablet formulated using design space showed a similar dissolution to that of Micardis® tablets at pH 7.5. The QbD approach TP tablet was bioequivalent to Micardis® tablets in beagle dogs.  相似文献   

19.
The objective of this study was to formulate directly compressible rapidly disintegrating tablets of fenoverine with sufficient mechanical integrity, content uniformity, and acceptable palatability to assist patients of any age group for easy administration. Effect of varying concentrations of different superdisintegrants such as crospovidone, croscarmellose sodium, and sodium starch glycolate on disintegration time was studied. Tablets were evaluated for weight variation, thickness, hardness, friability, taste, drug content, in vitro and in vivo disintegration time, and in vitro drug release. Other parameters such as wetting time, water absorption ratio (‘R’), and drug-excipient compatibility were also evaluated. The disintegration time of the best rapidly disintegrating tablet formulation among those tested was observed to be 15.9 sec in vitro and 37.16 sec in vivo. Good correlation was observed between disintegration time and ‘R’ for each of the three superdisintegrants at the concentrations studied. Considering the ‘R’ values and disintegration time, crospovidone was significantly superior (p < 0.05) compared to the other superdisintegrants tested. Release of drug was faster from formulations containing 6% crospovidone (CP 6) compared to the marketed fenoverine (Spasmopriv®) capsules. Similarity factor ‘f2’ (51.5) between dissolution profiles of the rapidly disintegrating tablet formulation CP 6 and the marketed formulation indicated that the two dissolution profiles were similar. Differential scanning calorimetric studies did not indicate any excipient incompatibility, either during mixing or after compression. In conclusion, directly compressible rapidly disintegrating tablets of fenoverine with lower friability, acceptable taste, and shorter disintegration times were obtained using crospovidone and other excipients at optimum concentrations.  相似文献   

20.
Abstract

Compactrol as a newly introduced direct compressible vehicle was used for the preparation of Diazepam and phenobarbitone sodium tablets. Spray dried lactose and wet granulation technique were also employed to prepare these tablets for comparison. The effect of storage at 75% RH, at two temperature levels (25° and 45°) on the physical properties of these tablets was studied for 6 weeks. It was found that, there were an increase in tablet weight, thickness and friability per cent, while a significant decrease in hardness was observed. Tablets prepared with compactrol showed no significant changes in both disintegration and dissolution times, while tablets prepared with spray dried lactose showed a marked decrease in disintegration and dissolution times. On the other hand, tablets prepared by wet granulation showed a pronounced in crease in both disintegration and dissolution times.  相似文献   

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