Additive effect of chondroitin sulfate and chitosan on drug release from calcium-induced alginate gel beads

Murata, Yoshifumi; Miyamoto, Etsuko; Kawashima, Susumu

doi:10.1016/0168-3659(95)00098-4

Cited by 64 publications

(30 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The release rate is a function of the degree of cross-linking between both polymers. An interaction between chitosan and the drug molecule was also observed (37,38). Other coatings like Eudragit Õ will also modify the release of drugs from alginate beads (39,40).…”

Section: Diffusion Systemsmentioning

confidence: 91%

Alginate in Drug Delivery Systems

Tønnesen

Karlsen

2002

Drug Development and Industrial Pharmacy

1,292

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

Section: Diffusion Systemsmentioning

confidence: 91%

Alginate in Drug Delivery Systems

Tønnesen

Karlsen

2002

Drug Development and Industrial Pharmacy

1,292

613

View full text Add to dashboard Cite

show abstract

“…36 In addition, an interpolymeric complex between chitosan and alginate could be partially formed at low pH. 37,38 Recently, the formation of a polyelectrolyte complex between chitosan and sodium alginate in pellets produced by twin-screw extruder has been confirmed. 16 These changes led to a slower drug release from the pellets containing chitosan and sodium …”

Section: Crushing Forcementioning

confidence: 97%

Influence of chitosan type on the properties of extruded pellets with low amount of microcrystalline cellulose

2007

View full text Add to dashboard Cite

The purpose of this research was to study the influence of type of chitosan with different molecular weights, ie, 190 and 419 kDa, on properties of pellets prepared by extrusion/ spheronization. The formulations, consisting of acetaminophen as model drug, chitosan, microcrystalline cellulose (MCC), and dibasic calcium phosphate dihydrate with/without sodium alginate, were extruded using a twin-screw extruder and water as the granulating liquid. With 30% wt/wt MCC and no added sodium alginate, spherical pellets were produced containing low and high molecular weight chitosan at a maximum amount of 60% and 40% wt/wt, respectively. With sodium alginate (2.5% wt/wt), pellets with either type of chitosan (60% wt/wt), MCC (17.5% wt/wt), and acetaminophen (20% wt/wt) could be produced indicating an improved pelletforming ability. Type and amount of chitosan and added sodium alginate affected physical properties of pellets including size, roundness, crushing force, and drug release. Low molecular weight chitosan produced pellets with higher mean diameter, sphericity, and crushing force. Additionally, the pellets made of low molecular weight chitosan and added sodium alginate showed faster drug release in 0.1 N HCl but had slower drug release in pH 7.4 phosphate buffer. This indicated that drug release from pellets could be modified by the molecular weight of chitosan. In conclusion, the molecular weight of chitosan had a major influence on formation, physical properties, and drug release from the obtained pellets.

show abstract

“…For ALG-CHIT complexes, the asymmetric -C-O-stretching disappeared and a new broad band with strong peak of amine coupled with amide II appeared, indicating that NH + 3 present in chitosan interacts with -COO − of alginate. Electrostatic binding resulted between alginate and chitosan, since at working pH, alginate was an anionic polymer in solution (Murata, Miyamoto, and Kawashima 1996) and chitosan was a cationic polymer, and the resulting complex is well documented (Becherán-Marón, Peniche, and Argüelles-Monal 2004;Gaserod, Smidsrod, and Skjak-Braek 1998;Lee, Park, and Ha 1997;Sankalia et al 2006;Tapia et al 2004).…”

Section: Discussionmentioning

confidence: 99%