Pullulan properties

Most frequently, SEC with dextran-, pullulan-, or polystyrene calibration standards has been used to characterize the molecular properties of xylans. However, as for viscometric studies [108], a sufficient solvent ionic strength is a prerequisite for useful SEC measurements of charged polysaccharides, including glucuronoxylans [111-113]. An advantage of the SEC technique is that the presence of protein and phenolic components or oxidative changes can be detected by simultaneous ultraviolet (UV) detection. 

Abstract Carbohydrates have been investigated and developed as delivery vehicles for shuttling nucleic acids into cells. In this review, we present the state of the art in carbohydrate-based polymeric vehicles for nucleic acid delivery, with the focus on the recent successes in preclinical models, both in vitro and in vivo. Polymeric scaffolds based on the natural polysaccharides chitosan, hyaluronan, pullulan, dextran, and schizophyllan each have unique properties and potential for modification, and these results are discussed with the focus on facile synthetic routes and favorable performance in biological systems. Many of these carbohydrates have been used to develop alternative types of biomaterials for nucleic acid delivery to typical polyplexes, and these novel materials are discussed. Also presented are polymeric vehicles that incorporate copolymerized carbohydrates into polymer backbones based on polyethylenimine and polylysine and their effect on transfection and biocompatibility. Unique scaffolds, such as clusters and polymers based on cyclodextrin (CD), are also discussed, with the focus on recent successes in vivo and in the clinic. These results are presented with the emphasis on the role of carbohydrate and charge on transfection. Use of carbohydrates as molecular recognition ligands for cell-type specific dehvery is also briefly... 

Films formed from pullulan have excellent physical properties, are... 

Lazaridou, A., and Biliaderis, C.G. (2002). Thermophysical properties of chitosan, chitosan-starch and chitosan-pullulan films near the glass transition. Carbohydrate Polymers. 48,... 

Properties and Occurrence of Dextrans, Alternan, Mutan, and Pullulan. 74... 

Pullulan is a glucan of (1 6)-a-D-linked maltotriose residues produced by Aureobasidium pullulans from starch or sucrose feedstockJ It is well soluble in aqueous medium and forms films that possess thermal stability and are antistatic and elastic. Pullulan has adhesive properties and is directly compressible under heat with moisture. The polysaccharide is produced on an industrial scale and is used for multiple applications, including food, pharmaceuticals, and cosmetics. It has recently been classified as GRAS by the U.S. FDA. 

One of the Aureobasidium fungi, Aureobasidium pullulans, is recommended by ASTM G 21 (see above) for the determination of the effect of fnngi on the properties of synthetic polymeric materials. 

Purified pullulan is a white, non-hygroscopic powder which dissolves in hot or cold water. Pullulan does not provide high viscosity solutions at low concentration. The most important property of pullulan is the ability to form films. The films are prepared by dissolving pullulan in water at 5-10% concentration and continually drying the solution applied to a smooth surface. The major advantage of pullulan films is the very low oxygen permeability. The oxygen permeability of pullulan films and three films of commerce are shown in Table IV. (3)... 

Pullulan films have several other advantages. The films are colorless, tasteless, odorless, transparent, resistant to oil and grease, and heat sealable. The properties of the films can be modified by chemical modification of pullulan, blending with poly-vinylalcohol, gelatin, or amylose, and by addition of plasticizers. These properties indicate that pullulan can be used as a coating or packaging for foods to prevent their oxidation. This is the only apparent outstanding application for pullulan. 

Kristo, E., Biliaderis, C.G. Physical properties of starch nanocrystal-reinforced pullulan films. Caibohydr. Polym. 68, 146-158 (2007)... 

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