Polysaccharide drug delivery systems based on pectin and chitosan

Abstract

Chitosans and pectins are natural polysaccharides which show great potential in drug delivery systems.Chitosans are a family of strongly polycationic derivatives of poly-N-acetyl-Dglucosamine. This positive charge is very important in chitosan drug delivery systems as it plays a very important role in mucoadhesion (adhesion to the mucosal surface). other chitosan based drug delivery systems involve complexation with ligands to form chitosan nanoparticles with can be used to encapsulate active compounds.Pectins are made of several structural elements the most important of which are the homogalacturonan (HG) and type I rhamnogalacturonan (RG-I) regions often described in simplified terms as the "smooth" and "hairy" regions respectively. Pectin HG regions consist of poly-glacturonic acid residues which can be partially methyl esterified. Pectins with a degree of methyl esterification (DM) > 50% are known as high methoxyl (HM) pectins and consequently low methoxyl (lM) pectins have a DM < 50%. low methoxyl pectins are of particular interest in drug delivery as they can form gels with calcium ion (Ca 2+ ) which has potential applications especially in nasal formulations.Biotechnology and Genetic Engineering Reviews -Vol. 27, 257-284 (2010) Polysaccharide drug delivery systems based on pectin and chitosan Chitosans are a family of strongly polycationic derivatives of poly-N-acetyl-Dglucosamine. This positive charge is very important in chitosan drug delivery systems as it plays a very important role in mucoadhesion (adhesion to the mucosal surface). Other chitosan based drug delivery systems involve complexation with ligands to form chitosan nanoparticles with can be used to encapsulate active compounds.Pectins are made of several structural elements the most important of which are the homogalacturonan (HG) and type I rhamnogalacturonan (RG-I) regions often described in simplified terms as the "smooth" and "hairy" regions respectively. Pectin HG regions consist of poly-glacturonic acid residues which can be partially methyl esterified. Pectins with a degree of methyl esterification (DM) > 50% are known as high methoxyl (HM) pectins and consequently low methoxyl (LM) pectins have a DM <50%. Low methoxyl pectins are of particular interest in drug delivery as they can form gels with calcium ion (Ca') which has potential applications especially in nasal formulations.

Biopolímeros: aplicações farmacêutica e biomédica

“…Nas pectinas de baixo grau de metoxilação, a formação Nos últimos anos, a pectina tem sido amplamente empregada pela indústria de alimentos como agente espessante, geleificante e estabilizante 46,59 . Dentro da área farmacêutica vem sendo explorada para o desenvolvimento de novos sistemas de liberação de fármacos, devido às propriedades promissoras desse material como baixa toxicidade, biocompatibilidade, degradabilidade e baixo custo 60,61 . Outra vertente muito explorada é a utilização da pectina como excipiente na obtenção de sistemas de liberação cólon-específica de fármacos, uma vez que em meio ácido permanece como agregados de macromoléculas, além de ser resistente às proteases e às amilases presentes nas porções superiores do trato gastrintestinal (TGI), sendo degradada por enzimas produzidas pela microbiota colônica 44,50,57 .…”

Microbial Pectic Enzymes in the Food and Wine Industry

“…The pharmaceutical industry offers them as preparations to reduce cholesterol or to act as a lubricant in the intestines thus promoting normal peristaltic movement without causing irritation. In addition, these polysaccharides are used as drug delivery systems, which can also reduce the toxicity of these and make their activity longer lasting without altering their therapeutic effects (Morris et al, 2010;Pilnik & Voragen, 1970;Schols et al, 2009;Thakur et al, 1997 …”

Complexes of Polysaccharides and Glycyrrhizic Acid with Drug Molecules − Mechanochemical Synthesis and Pharmacological Activity

“…An important relevant issue is to enhance the efficacy and safety of pharmaceutical compounds by correcting their solubility [1][2][3]. Polysaccharides (e.g., derivatives of cellulose, chitosan, and alginic and hyaluronic acids) make part of compositions with controlled or retarded drug release [4][5][6], while oligosaccharides (alpha-, beta-, and gamma-cyclodextrins and their derivatives) are broadly used to increase solubility and dissolution rates as they can form guest-host supramolecular complexes with poorly soluble drugs [7,8]. Until recently little was known whether complexes of this kind may result from the activity of natural plantderived or synthetic water-soluble polysaccharides though these are common elements in dietary supplements or drugs.…”