Formulation and in vitro evaluation of ibuprofen-carbopol® 974P-NF controlled release matrix tablets III: influence of co-excipients on release rate of the drug

Khan, Gul Majid; Zhu, Jin

doi:10.1016/s0168-3659(97)00225-3

Cited by 85 publications

(50 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Carbopol is a cross-linked polymer, which results in a remarkable increase in the molecular volume and reduces the free volume. It is more difficult for a drug molecule to move through a tightly cross-linked network (strong entanglement) [19] than it is to pass through a linear structure like sodium alginate. Furthermore, due to extended swelling and limited erosion, the drug molecule has to follow a longer diffusional path.…”

Section: Drug-release Studiesmentioning

confidence: 99%

Development and Evaluation of oral multiple-unit and single-unit hydrophilic controlled-release systems

2000

View full text Add to dashboard Cite

This study compared the release behavior of single-unit (tablets, capsules) and multipleunit (minitablets in capsules) controlled-release systems of furosemide. The swelling and erosion behaviors of these systems, which contained the swellable hydrophilic polymers sodium alginate (high viscosity) and Carbopol 974P, were compared. Swelling and erosion experiments showed a high degree of swelling and limited erosion for the Carbopol preparations, whereas less swelling but greater erosion was observed for the sodium alginate preparations. The sodium alginate preparations were eroded in 6 hours, while Carbopol preparations exhibited limited erosion within this period of time. These results appear to be attributed to the physicochemical characteristics of the polymers used in this study. Polymer characteristics greatly influenced the release of furosemide (model drug) from the formulations prepared and tested. Sodium alginate had a less pronounced sustained release effect compared with Carbopol (ie, in 8 hours all 3 sodium alginate dosage forms displayed complete release of furosemide, while only 30% of the drug was released from Carbopol dosage forms). Finally, all 3 Carbopol dosage forms (single-and multiple-unit) displayed similar release behavior while sodium alginate dosage forms displayed a different and more distinctive behavior. Minitablets and tablets showed a greater sustained release effect compared with capsules. Evaluation of the release data indicates that the release mechanism for sodium alginate formulations may be attributed to erosion/dissolution, while for Carbopol it may be attributed mainly to polymer relaxation and diffusion of the drug from the polymer surface.

show abstract

Section: Drug-release Studiesmentioning

confidence: 99%

Development and Evaluation of oral multiple-unit and single-unit hydrophilic controlled-release systems

2000

View full text Add to dashboard Cite

show abstract

“…This may be due to hydration of the polymer matrix as it it swells on contact with water and thus closes up the microspores in the swollen tablet, causing a decrease in drug release from the tablet [5]. Furthermore, increase in the amount of the carbomer resulted not only in a reduction of drug release rate but linearization of the drug release curve, leading to a shift towards a swellingcontrolled mechanism.…”

Section: Discussionmentioning

confidence: 99%

“…Carbopols or carbomers (hydrophilic polymer) compress very well and have strong binding characteristics which make them ideal for direct compression process. They show compatibility with various active ingredients and other excipients [4,5]. Carbopol 974P and Carbapol 934 are oral pharmaceutical grades of carbomers.…”

Section: Introductionmentioning

confidence: 99%

Formulation and Evaluation of Tramadol HCl Matrix Tablets Using Carbopol 974P and 934 as Rate-Controlling Agents

Rehman¹,

Khan²,

Shah³

et al. 2013

Trop. J. Pharm Res

View full text Add to dashboard Cite

“…Thus, since water is used as a solvent in this study unlike conventional solid dispersion method, this solid dispersion method has several advantages over other methods in an industry scale, such as the relatively lower ratio of carriers to drug, no necessity to remove organic solvent and no toxicity or explosion of organic solvent. 39,40) Effects of Aqueous Solubility of Sibutramine Base in the Solid Dispersions To select an optimal formula of sibutramine base-loaded solid dispersion which increased the drug solubility with the minimum amount of carriers, the effect of the ratio of HPMC/poloxamer ( Table 1, formula I-III) on the aqueous solubility of sibutramine was shown in Fig. 1A.…”

Section: Preparation Of Sibutramine-loaded Solid Dispersionmentioning

confidence: 99%

Enhanced Solubility and Bioavailability of Sibutramine Base by Solid Dispersion System with Aqueous Medium

Jang

Kang

et al. 2010

Biological & Pharmaceutical Bulletin

View full text Add to dashboard Cite

Sibutramine [1-(4-chlorophynyl)-N,N-dimethyl-a-(2-methylpropyl)cyclobutane methane amine] is a newer antiobesity drug with a novel mechanism of action.1) It contains a potent inhibitor of the reuptake of noradrenaline (NA), serotonin (5-HT) and may stimulate thermogenesis by its activation of b 3 -adrenoceptors in brown adipose tissue. [2][3][4] In human subjects, sibutramine is rapidly metabolized to an Nmono-desmethyl metabolite (desmethylsibutramine [Metabolite I]) and an N,N-didesmethyl metabolite (didesmethylsibutramine [Metabolite II]). The in vivo effects of sibutramine are predominantly the results of the action of the above 2 metabolites. 4-7)Sibutramine hydrochloride monohydrate is the commercially available formulation of sibutramine with the relatively high solubility of 2.9 mg/ml at pH 5.2 and melting point of 190°C. 4,8) However, sibutramine base with low solubility has not been used in commercial formulation. Various oral formulations of sibutramine such as another salt form such as sibutramine mesylate 9,10) and sibutramine tartrate, 11) solid dispersions with poloxamer [12][13][14] and inclusion complex. 15)One of the well established method for increasing the solubility and bioavailability of poorly water-soluble drugs is solid dispersion.16) Several conventional methods such as melting, solvent evaporation and solvent wetting were reported to prepare solid dispersions. 17,18) However, the solid dispersion prepared by melting method with high temperature might chemically decompose the drugs. 19,20) In the case of solvent evaporation and solvent wetting method, the drug in the solid dispersions changed to amorphous form, resulting that the drug might be unstable. 18) Furthermore, a large amount of hydrophilic carriers against drug in these conventional solid dispersions must be needed to improve the solubility of poorly water-soluble drugs. 21,22) In this study, to improve the bioavailability of poorly water-soluble sibutramine base, various sibutramine baseloaded solid dispersions were prepared with water, hydroxypropylmethyl cellulose (HPMC), poloxamer and citric acid using spray-drying technique. The effect of HPMC, poloxamer and citric acid on the aqueous solubility of sibutramine was then investigated. The physicochemical properties of solid dispersion were investigated using scanning electron microscope (SEM), differential scanning calorimetry (DSC) and X-ray powder diffraction. The dissolution and pharmacokinetics in rats of solid dispersion were evaluated compared to the sibutramine hydrochloride monohydrate-loaded commercial product (Reductil ® ). This commercial product is a conventional capsule which contains 100 mg sibutramine hydrochloride monohydrate and is usually taken multiple times a day. Poloxamer has been employed to enhance the solubility and bioavailability of poorly water-soluble drugs. 19,23) HPMC is frequently used in the preparation of conventional pharmaceutical oral dosage form due to its hydrophilic and soft property. 24,25) To develop a novel sibutramine base-...

show abstract

Formulation and in vitro evaluation of ibuprofen-carbopol® 974P-NF controlled release matrix tablets III: influence of co-excipients on release rate of the drug

Cited by 85 publications

References 6 publications

Development and Evaluation of oral multiple-unit and single-unit hydrophilic controlled-release systems

Development and Evaluation of oral multiple-unit and single-unit hydrophilic controlled-release systems

Formulation and Evaluation of Tramadol HCl Matrix Tablets Using Carbopol 974P and 934 as Rate-Controlling Agents

Enhanced Solubility and Bioavailability of Sibutramine Base by Solid Dispersion System with Aqueous Medium

Contact Info

Product

Resources

About