Hydroxypropylmethyl cellulose acetate

FIGURE 18.10 Inhibitory effect of polymers on recrystallization of nifedipine (NP) from a supersaturated solution at pH 6.8. HPMCAS, hydroxypropylmethyl cellulose acetate succinate HPMC, hydroxypropylmethyl cellulose HPMCP, hydroxypropylmethyl pthate PVP, polyvinyl pyrrolidone MAEA, methacrylic acid ethyl acrylate copolymer. (From Tanno, F., Y. Nishiyama, H. Kokubo, S. Obara. ZWMjDev Ind Pharm30 13. 

Cellulose acetate Cellulose acetate butyrate Cellulose acetate phthalate Cellulose acetate propionate Ethyl cellulose Hydroxyethyl cellulose Hydroxypropyl cellulose Hydroxyethylmethyl cellulose Hydroxypropylmethyl cellulose Hydroxypropylmethyl cellulose acetate succinate Hydroxypropylmethyl cellulose phthalate Methyl cellulose Na Carboxymethyl cellulose... 

Hoshi N, Ueno K, Yano H, Hirashima K, Kitagawa H. General pharmacological studies of hydroxypropylmethyl cellulose acetate succinate in experimental animals. / Toxicol Sci 1985 10 129-146. 

Hoshi N, Ueno K, Igarashi T, et al. Effects of offspring induced by oral administration of hydroxypropylmethyl cellulose acetate succinate to the female rats in peri and post natal periods. J Toxicol Sci 1985 10 235-255. 

Hydroxypropylmethyl cellulose acetate succinate ASM, AS-H Shin-Etsu Chemical Co., Japan Ltd. 

The most commonly used polymers are cellulose acetate phthalate [9004-38-0] (CAP), poly(vinyl acetate phthalate) [34481-48-6] (PVAP), hydroxypropylmethyl-ceUulosephthalate [71138-97-1] (HPMCP), and polymethacrylates (111) (see Cellulose esters). Acrylate copolymers are also available (112). Eigure 11 shows the dissolution behavior of some commercially available enteric materials. Some manufacturers supply grades designed to dissolve at specific pH values with increments as small as 0.5 pH unit (113). 

Schulze et al. [135] developed fused-silica chips dynamically coated with hydroxypropylmethyl cellulose and utilized them for the separation of aromatic low molecular weight compounds such as serotonin, propranolol, a diol, and tryptophan. The authors used deep UV laser-induced fluorescence detection for these compounds. Schuchert-Shi et al. [136] identified ethanol, glucose, ethyl acetate, and ethyl butyrate, byproducts obtained in enzymatic conversions using hexokinase, glucose oxidase, alcohol dehydrogenase, and esterase. The authors reported that the quantification for ethyl acetate was possible using contactless conductivity detection. Hu et al. [137] described the separation of reaction products of (3-thalassemia in a multiplex primer-extension reaction using NCE. The method developed was used for patient samples and the results coincided with those of a detection kit. 

Water-soluble hydroxypropylmethyl cellulose and water-insoluble cellulose acetate are further treated with phthalic anhydride or succinic anhydride to yield hydroxypropyl methylcellulose phthalate, cellulose acetate phthalate, and hydroxypropyl-methylcellulose acetate succinate. These polymers are used as enteric materials and are water soluble or insoluble above or below a specific pH, respectively. 

Cellulose, 2-hydroxypropylmethyl ether, acetate hydrogen butanedioate [71138-97-1]... 

Hypromellose acetate succinate is a mixture of acetic acid and monosuccinic acid esters of hydroxypropylmethyl cellulose. It is available in several grades, which vary in extent of substitution, mainly of acetyl and succinoyl groups, and in particle size (fine or granular). When dried at 105°C for one hour, it contains 12.0-28.0% of methoxy groups 4.0-23.0% of hydroxypropoxy groups 2.0-16.0% of acetyl groups and 4.0-28.0% of succinoyl groups. 

Lincomycin hydrochloride and aminoglycoside hydrochloride were determined in pharmaceuticals by Isotachophoresis. In this method, a mixture of 0.02 M potassium acetate and 0.3 % hydroxypropylmethyl cellulose (15,000) was used as an aqueous electrolyte system, whereas a mixture of 20um 1,4-aminobutyric acid in acetic acid (pH 4.72) or 0.02 M glycylglycine or B -alanine was used as the terminator. The analysis was performed at a constant current of 200 jjA at 5°C. it was found that the minimum amount that could be quantitated by this method was 1.6 nmol and the relative standard deviation was 2%. 

Cellulose acetate phthalate (CAP) Hydroxypropylmethyl cellulose (HPMCP) Poly(methacrylates)... 

Ethyl cellulose Hydroxyethyl cellulose Hydroxypropyl cellulose Methyl cellulose Cellulose acetate Hydroxypropylmethyl cellulose Hydroxybutylmethyl cellulose Hydroxyethylmethyl cellulose Ethylhydroxyethyl cellulose Cellulose xanthate... 

Hydroxypr opylm ethyl cellulose acetate succinate By the esterification of hydroxypropylmethyl cellulose with acetic anhydride and succinic anhydride Film coating. Enteric coating... 

PVOH miscibility has been noted with poly(N, N-dimethyl acrylamide) [962] and partial miscibility noted with methyl cellulose [963]. With poly(N, N-dimethyl acrylamide), vinyl alcohol-vinyl acetate copolymers are miscible above 12 mole% vinyl alcohol. Fully hydrolyzed PVOH is not miscible with poly(2-ethyl oxazoline)(PEOx), but ethylene-vinyl alcohol copolymers (68 and 78 mole% vinyl alcohol) are miscible with PEOx [964]. Vinyl acetate-vinyl alcohol copolymers were shown to be miscible with PEOx over a wide range of copolymer compositions [965]. The immiscibility of fully hydrolyzed PVOH was attributed to the hydroxyl self-association dominating the competing hydroxyl-amide association. PVOH blends with sodium polystyrene sulfonate gave flexible, transparent films with good electrical conductivity [966]. Phase separation of PVOH/PEO [967] and PVOH/hydroxypropylmethyl cellulose blends [968] has been reported. PVOH/polyethyleneimine blends have been studied for membrane separations involving isomer separation [969]. PVOH/poly(ethyl oxazoline) blends have noted in a series of patent applications related to proton-conducting membranes [970]. 

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