Cellulose derivatives gelatine

Polysorbates or sorbitan esters, acacia, and tragacanth Aluminum magnesium silicate, bentonite, carbomers, cellulose derivatives, gelatin, pectin, polyvinyl alcohol, alginates, starch, and xanthan gum Borates, citrates, acetates, and phosphates... 

These stabilizers are added to the formulation in order to stabilize the emulsion formed during particle preparation. These stabilizers, however, can also influence the properties of the particles formed. The type and concentration of the stabilizer selected may affect the particle size. Being present at the boundary layer between the water phase and the organic phase during particle formation, the stabilizer can also be incorporated on the particle surface, modifying particle properties such as particle zeta potential and mucoadhesion (203). Other polymers have also been evaluated as stabilizers in earlier studies such as cellulosic derivatives methylcellu-lose (MC), hydroxyethylcellulose ( ), hydroxypropylcellulose (HPC), and hydroxypropylmethylcellulose (HPMC), as well as gelatin type A and B, carbomer and poloxamer (203). 

Mucoadhesives are generally macromolecular organic polymers made from natural (gelatin, agarose, chitosan, hyaluronic acid) or synthetic polymers (polyvinylpyrrolidone (PVP), polyacrylates, polyvinyl alcohol, cellulose derivates). They possess hydrophilic groups that can... 

In addition to synthetic biodegradable polymers discussed so far, naturally occurring biopolymers have also been used for fabricating implantable dmg delivery systems. Examples of natural biopolymers are proteins (e.g. albumin, casein, collagen, and gelatin) and polysaccharides (e.g. cellulose derivatives, chitin derivatives, dextran, hyaluronic acids, inulin, and starch). 

Binders Polyvinyl pyrrolidone, starch, gelatin, cellulose derivatives... 

Cellulose derivatives Chitosans Gelatin Sodium carboxymethylcellulose (NaCMC) Methylcellulose (MC) Hydroxypropyl methylcellulose (HPMC) Hydroxypropyl cellulose (HPC) Hydroxyethyl cellulose (HEC)... 

Gelatin and cellulose derivatives are probably the most widely used polymers in simple coacervation... 

A protective colloid, such as gelatin, gum, or a cellulosic derivative, is used to form a film barrier around the particles, inhibiting dissolution and subsequent crystal growth. 

Povidone can also be used as a hydrophilic component or pore former in preparations that contain sustained-release auxiliaries like polyvinyl acetate, cellulose derivatives like HPMC [490, 509, 660], alginate [461], cetylacohol [600], polylactic acid [5o6],Gelucire [510],polyvinyl alcohol [522],ceresine wax [523], stearic acid [606] or methacrylate copolymers [491] to control or regulate the release of active substances, as binders and/or sometimes as plasticizers. They can also be extruded together with the active substance in melted stearyl alcohol and filled into hard gelatin capsules to achieve the same effect [471]. Ocular delivery systems are also described [598]. 

Suitable protective colloids for the preparation of acrylic suspension polymers include cellulose derivatives, polyacrylate salts, starch, poly(vinyl alcohol), gelatin, talc, clay, and clay derivatives (95). These materials are added to prevent the monomer droplets from coalescing during polymerization (110). Thickeners such as glycerol, glycols, polyglycols, and inorganic salts are also often added to improve the quality of acrylic suspension polymers (95). 

Natural polymers have also been used as thermo-sensitive hydrogels, either on their own or in combination with other synthetic polymers. Popular natural polymers include chitosan, cellulose derivatives, dextran, xyloglucan and gelatin (Klouda and Mikos 2008). Chitosan is a polysaccharide derived from the shells of crustaceans and is produced by deacetylation of chitin, basically through the removal of the acetyl group using a concentrated NaOH solution (Fig. 11.5). The main advantage of chitosan for medical and pharmaceutical applications is its biocompatibility and inertness when in contact with human cells (Kumar et al. 

Preparations of azide derivatives from styrene-maleic anhydride copolymers, cellulose, and gelatin by attaching aromatic azide compounds are described in the literature. Most of the resultant polymers crosslink rapidly when exposed to light of 260 wavelength. Also, as much as 90% of the hydroxy groups of poly(vinyl alcohol) can be esterified withp-azido-benzoyl chloride. These reactions must be carried out in mixtures of chloroform and aqueous sodium hydroxide. Based on infrared spectroscopy, the following crosslinking mechanism was proposed ... 

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