Chitosan‐Catechol Conjugates–A Novel Class of Bioadhesive Polymers

Nifedipine is an antihypertensive BCS class II drug which has poor bioavailability when given orally. The objective of the present study was to increase the bioavailability of nifedipine, by formulation and evaluation of a buccoadhesive liquisolid system using magnesium aluminium silicate (Neusilin) as both carrier and coating material and dissolution media were selected based on the solubility studies. A mixture of carboxymethylcellulose sodium and carbomer was used as mucoadhesive polymers. Buccoadhesive tablets were prepared by direct compression. FTIR studies confirmed no interaction between drug and excipients. XRD studies indicated change/reduction in crystallinity of drug. The powder characteristics were evaluated by different flow parameters to comply with pharmacopoeial specifications. The dissolution studies for liquisolid compacts and tablet formulations were carried out and it was found that nifedipine liquisolid tablets formulated from bioadhesive polymers containing 49% liquisolid system, 17.5% carbomer, and 7.5% carboxymethylcellulose sodium showed the best results in terms of dissolution properties. Prepared formulation batches were evaluated for swelling, bioadhesion strength, ex vivo residence time, and permeability studies. The optimized batch was showing promising features of the system. Formulating nifedipine as a buccoadhesive tablet allows reduction in dose and offers better control over the plasma levels.

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Bioadhesive properties of β-limit dextrin

Journal of Pharmacy & Pharmaceutical Sciences ◽

10.18433/j3459b ◽

2011 ◽

Vol 14 (1) ◽

pp. 60 ◽

Cited By ~ 7

Author(s):

XIN QI ◽

Richard F Tester

Keyword(s):

Drug Delivery ◽

Pharmaceutical Industry ◽

Synthetic Polymers ◽

Salivary Amylase ◽

Delivery Methods ◽

Internal Structures ◽

Bioadhesive Polymers ◽

Mouth Feel ◽

Potential Use

Purpose. β-Limit dextrin has been studied for many years as a means to investigate the internal structures of amylose and amylopectin. However its role as an excipient in the pharmaceutical industry has never been reported. This paper is the first one in a series to explore its potential use as an excipient to aid drug delivery. Methods. The bioadhesive properties of β-limit dextrin were studied using a texture analyser and compared with two well-known bioadhesive polymers – carbopol and chitosan (as controls). Results. The β-limit dextrin has significant mucoadhesive properties; similar to carbopol but superior to chitosan. Conclusions. The nature of β-limit dextrin (a starch derivative) makes it safe to consume and provides a natural alternative when compared with synthetic polymers. In addition, the polysaccharide can be digested by salivary amylase and thus provide a clean mouth feel.

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FORMULATION OF RIZATRIPTAN BENZOATE SUBLINGUAL TABLETS PREPARED BY DIRECT COMPRESSION WITH DIFFERENT BIOADHESIVE POLYMER: IN VITRO AND EX VIVO EVALUATION

Asian Journal of Pharmaceutical and Clinical Research ◽

10.22159/ajpcr.2017.v10s4.21334 ◽

2017 ◽

Vol 10 (16) ◽

pp. 36

Author(s):

Harmanpreet Singh ◽

Pooja Jaiswal ◽

Suksham Gupta ◽

Simerjit Singh

Keyword(s):

Ex Vivo ◽

Methyl Cellulose ◽

Systemic Circulation ◽

Direct Compression ◽

Compression Process ◽

Rizatriptan Benzoate ◽

Dissolution Tests ◽

Ex Vivo Permeation ◽

Bioadhesive Polymers

Objective: The current investigation deals with formulation and evaluation of fast disintegrating sublingual tablets of rizatriptan benzoate (RTB) to produce its intended therapeutic effect for acute treatment of migraine. When the drug is given by sublingual route, it overcomes the first pass metabolism and quick entry of drug in systemic circulation is obtained. It would result in fast pharmacological response hence faster relief from migraine which is an important criterion in migraine therapy.Methods: In this study, RTB sublingual tablets were prepared using direct compression process using various bioadhesive polymers such as sodium carboxymethyl cellulose, hydroxyl propyl methyl cellulose-K4M, and chitosan at various concentration ranging 0.5-5% w/w along with sodium starch glycolate (SSG) or cross carmellose sodium (CCS) as super disintegrants at different concentration ranging 2-8% w/w.Results: The tablets disintegrated quickly and dissolution tests conclude that RTB was released from the formulation within the compendial limits. The formulations batches (A8 and B8) containing 2% w/w chitosan along with 2% w/w SSG or CCS which disintegrate rapidly and show high dissolution and ex vivo permeation were selected as optimized formulations.Conclusion: The results obtained from the study showed that the bioavailability problem of the drug has been solved as the drug is given by sublingual route and it directly enters into systemic circulation. Furthermore, the formulation overcomes the problems associated with migraine attack as fast disintegrating technology is used.

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