Drug release from oral mucosal adhesive tablets of chitosan and sodium alginate

Miyazaki, Shôzo; Nakayama, Akihisa; Oda, Masayuki; Takada, Masahiko; Attwood, David

doi:10.1016/0378-5173(94)00396-m

Cited by 76 publications

(34 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The adhesive properties increased with an increase in homogeneity of the beads. Alginate/chitosan tablets have been prepared for adhesion to human cheek mucosa (64,65).…”

Section: Modulation Of Gastrointestinal Transit Timementioning

confidence: 99%

Alginate in Drug Delivery Systems

Tønnesen

Karlsen

2002

Drug Development and Industrial Pharmacy

1,260

613

View full text Add to dashboard Cite

Alginates are established among the most versatile biopolymers, used in a wide range of applications. The conventional use of alginate as an excipient in drug products generally depends on the thickening, gel-forming, and stabilizing properties. A need for prolonged and better control of drug administration has increased the demand for tailor-made polymers. Hydrocolloids like alginate can play a significant role in the design of a controlled-release product. At low pH hydration of alginic acid leads to the formation of a high-viscosity ''acid gel.'' Alginate is also easily gelled in the presence of a divalent cation as the calcium ion. Dried sodium alginate beads reswell, creating a diffusion barrier decreasing the migration of small molecules (e.g., drugs). The ability of alginate to form two types of gel dependent on pH, i.e., an acid gel and an ionotropic gel, gives the polymer unique properties compared to neutral macromolecules. The molecule can be tailor-made for a number of applications. So far more than 200 different alginate grades and a number of alginate salts are manufactured. The potential use of the various qualities as pharmaceutical excipients has not been evaluated fully, but alginate is likely to make an important contribution in the development of polymeric delivery systems. This natural polymer is adopted by Ph.Eur. It can be obtained in an ultrapure form suitable for implants. This review discusses the present use and future possibilities of alginate as a tool in drug formulation.

show abstract

“…The adhesive properties increased with an increase in homogeneity of the beads. Alginate/chitosan tablets have been prepared for adhesion to human cheek mucosa (64,65).…”

Section: Modulation Of Gastrointestinal Transit Timementioning

confidence: 99%

Alginate in Drug Delivery Systems

Tønnesen

Karlsen

2002

Drug Development and Industrial Pharmacy

1,260

613

View full text Add to dashboard Cite

show abstract

“…At a high degree it is highly charged and has an extended confirmation with more flexible chains, whereas at a lower degree of deacetylation the chitosan molecule adopts a rod-or coillike shape because of low charges. [3][4][5][6][7][8][9][10] Chitosan drug complexes, chitosan beads, and polymers have been reported in the literature. [9][10][11][12][13][14][15][16][17] Carrageenans are naturally occurring high molecular weight polysaccharides extracted from seaweeds and are made up of the repeating units of galactose and 3,6 anhydrogalactose.…”

Section: Introductionmentioning

confidence: 99%

Effect of oppositely charged polymer and dissolution medium on swelling, erosion, and drug release from chitosan matrices

et al. 2007

View full text Add to dashboard Cite

The purpose of this research was to investigate the potential use of anionic κ-carrageenan and nonionic hydroxypropylmethylcellulose (HPMC, K4) to improve the matrix integrity of directly compressed chitosan tablets containing naproxen sodium, an anionic drug. The influence of buffer pH and drug:polymer ratio on the water uptake, matrix erosion, and drug release were studied. The rapid release of naproxen sodium was seen from matrices containing 100% chitosan due to loss in the matrix cohesiveness; whereas, it was relatively slow for matrices containing optimum concentration of κ-carrageenan. In-situ interaction between oppositely charged moieties resulted in the formation of polyelectrolyte complexes with stoichiometric charge ratios of unity. Fourier transform infrared (FTIR) spectroscopy and powder x-ray diffraction (PXRD) data confirmed the importance of ionic bonds in polyelectrolyte complexation. The ionic interactions between polymers were absent in matrices containing HPMC and the integrity of tablets was improved owing to the presence of viscous gel barrier.The reasons for retarded release of naproxen sodium from the chitosan matrices at different pH include poor aqueous solubility of drug, the formation of a rate-limiting polymer gel barrier along the periphery of matrices, the interaction of naproxen sodium with protonated amino groups of chitosan, and the interaction of ionized amino groups of chitosan with ionized sulfate groups of κ-carrageenan.

show abstract

“…Examples of earlier studies include an illustration of the directly compressible nature of chitosan [16], and mucoadhesion, rapid drug release rates from the dosage forms, and good bioavailability [17]. The latter study used a combination of chitosan and sodium alginate with diltiazem as the drug.…”

Section: Chitosanmentioning

confidence: 98%