Tablet pharmaceutical dosage form

As a therapeutic agent, ch oline is adininistered orally in the form of symps or elixers containing the chloride, citrates or bitartrate, or in the form of compressed tablets or capsules of the dihydrogen citrate. Choline is also given in small doses as a nutritional supplement in combination with a variety of other materials. In dry pharmaceutical-dosage forms, the dihydrogen citrate is usually preferred because of its lower tendency to absorb atmospheric moisture. Both salts have been used parenteraHy. 

Latices and pseudolatices are widely used for the coating of solid pharmaceutical dosage forms such as tablets, capsules, and pellets. The major advantage compared to conventional coating techniques is the avoidance of organic solvents. 

Rao et al. [45] determined primaquine phosphate, in pharmaceutical dosage forms, by using a colorimetric method. Powdered tablets containing the equivalent of 100 mg of primaquine phosphate were heated with 25 mL of water for 10 min, the solution was cooled and filtered, and 10 mL portion of the filtrate was diluted 10-fold with water. A 5-mL portion of this solution was mixed with 5 mL of pH 5 buffer solution, 1 mL of 0.08%. amidopyrine solution in aqueous 95% alcohol and 2 mL of aqueous 0.1% sodium periodate. After 10 min, 0.5 mL of aqueous sodium metabisulfite solution was added and the absorbance was measured at 580 nm. Beer s law was obeyed between 4 and 43 pg/mL of primaquine phosphate. Recoveries were quantitative. 

Lieberman, H.A., Lachman, L., and Schwartz, J.B., Eds., Pharmaceutical Dosage Forms Tablets, Vols. I—III, Marcel Dekker, New York, 1990. 

The inclusion of the a routine microbial limit test in a marketed product stability protocol depends on the pharmaceutical dosage form. Typically, the test would be used only for nonsterile products, especially oral liquids, nasal sprays, and topical liquids, lotions, and creams that have sufficient water activity to support the growth of microorganisms. In contrast, tablets, powder- and liquid-filled capsules, topical ointments, vaginal and rectal suppositories, nonaqueous liquids and inhalation aerosols with a water activity too low to allow for the product to support the growth of microorganisms would not be routinely tested. 

J.D. Kirsch and J.K. Drennen, Near-infrared spectroscopy applications in the analysis of tablets and solid pharmaceutical dosage forms, Appl Spectrosc. Rev., 30(3), 139-174 (1995). 

Lieberman HA, Lachman L. Pharmaceutical Dosage Forms Tablets, 2nd edn. New York Marcel Dekker, 1992. 

Sadana and Gaonkar have simultaneously determined diloxanide furoate and tinidazole in pharmaceutical dosage form by gas liquid chromatography [37]. Powdered tablets or suspension formulations were dissolved in chloroform, the solution filtered, and then diluted to 25 mL with chloroform. The solution also contained metronidazole as an internal standard. A 600 nL aliquot was analyzed on a stainless steel column (1 m X 3.2 mm) containing 3% of OV-17 on Chlorosorb W-UP (100-120 mesh). The GC system was operated at 200°C, using nitrogen as the carrier gas (45 mL/min). Flame ionization detection was used to observe the analytes. 

Porter SC, Bruno CH. In Lieberman HA, Lachman L, Schwartz JB, eds. Pharmaceutical Dosage Forms Tablets. Vol. 3. 2nd ed. New York Marcel Dekker, f990 77-i60. 

Nash, R. A. (1990), The essential of process validation, in Pharmaceutical Dosage Forms, Tablets, Marcel Dekker Inc, New York. 

Dhumal et al. [26] described an individual UV spectrophotometric assay method for the analysis of omeprazole from separate pharmaceutical dosage forms. Powdered tablets, equivalent to 50 mg of the drug, were sonicated with 35 ml of 0.1 M sodium hydroxide for 5 min and diluted to 50 ml with 0.1 M sodium hydroxide. The solution was filtered and a 2-ml portion of the filtrate was diluted to 200 ml with 0.1 M sodium hydroxide before the absorbance of the solution was measured at 305 nm versus 0.1 M sodium hydroxide. Beer s law was obeyed for 6-25 /[Pg.205]

Microcrystalline Cellulose. Microcrystalline cellulose is a purified, partially depolymerized cellulose that occurs as a white, odorless, tasteless, crystalline powder composed of porous particles. It is widely used in pharmaceutical dosage forms, primarily as a filler-binder in oral tablets and capsules with both wet granulation and direct compression processes. Microcrystalline cellulose was marketed first in 1964 by the FMC Corporation under name Avicel PH in four different particle size grades, each with different properties.37 Addition of Avicel into a spray-dried lactose-based formulation overcame compressibility problems. At the same time, the lactose enhanced the flowability of the Avicel products available at that time. The direct compression tableting process became a reality, rather than a concept, partially because of the availability of Avicel. As of 2007, Avicel PH is commercially available in 10 types with different particle size, density, and moisture grades that have different properties and applications (Table 7.6).38 Other brands of microcrystalline cellulose are also available on the pharmaceutical market, including Pharmacel 101 and 102 from DMV International and Emcocel 50 M and 90 M from JRS Pharma. 

Lantz RJ Jr, Schwartz JB. 1990. Mixing. In Lieberman HL, Lachman L, Schwarts JB, editors. Pharmaceutical dosage forms Tablets vol. 2, 2nd ed. New York Marcel Dekker 1-71. 

For a very long time, scientists generally underestimated the importance of excipients in pharmaceutical dosage forms. Excipients were cheap ingredients viewed solely as inert supports for medicaments. Today, with modern pharmaceutical excipients on the shelf, development of various novel drug delivery systems, and production with high-speed tablet/capsule machines, excipients are rather more than the sugar in the pill.9,10... 

Panderi and Parissi-Poulou developed a microbore liquid chromatographic method for the simultaneous determination of benazepril hydrochloride and hydrochlorothiazide in pharmaceutical dosage forms [30]. The use of a BDS C-18 microbore analytical column was found to result in substantial reduction in solvent consumption and in increased sensitivity. The mobile phase consisted of a mixture of 25 mM sodium dihydrogen phosphate buffer (pH 4.8) and acetonitrile (11 9 v/v), pumped at a flow rate of 0.4 mL/min. Detection was effected at 250 nm using an ultraviolet absorbance detector. The intra- and inter-day relative standard deviation values were less than 1.25% (n = 5), while the relative percentage error was less than 0.9% (n = 5). The detection limits obtained according to the IUPAC definition were 0.88 and 0.58 pg/mL for benazepril hydrochloride and hydrochlorothiazide, respectively. The method was applied to the quality control of commercial tablets and content uniformity test, and proved to be suitable for rapid and reliable analysis. 

Hassib et al. developed two chromatographic procedures for the simultaneous determination of benazepril hydrochloride and hydrochlorothiazide in laboratory made mixtures, and in pharmaceutical dosage forms (Cibadrex tablets) using reversed phase HPLC and TLC methods [24]. For reversed phase HPLC, a very sensitive, rapid, and selective method was developed. The linearity ranges were 32-448 ng/ 20 pL and 40-560 ng/20 pL for benazepril hydrochloride and hydrochlorothiazide, respectively. The corresponding recoveries were 99.38 1.526 and 99.2 1.123. The minimum detection limits were 7 ng/20 pL for benazepril and 14 ng/20 pL for hydrochlorothiazide. The method could be successfully applied for the determination of laboratory made mixtures and for pharmaceutical dosage forms. The results obtained were compared with those obtained by a spectrophotometric method. 

Davis SS, Hardy JG, Fara JW (1986) Transit of pharmaceutical dosage forms through the small intestine. Gut 27 886-892 Hardy JG, Wilson CG, Wood E (1985) Drug delivery to the proximal colon. J Pharm Pharmacol 37 874-877 Hardy JG, Healy JNC, Lee SW, Reynolds JR (1987) Gastrointestinal transit of an enteric coated delayed release 5-aminosalicylic acid tablet. Aliment Pharmacol Ther 1 209-216... 

Study of Ternary Tablets Percolation theory has been developed for binary systems, however, drug delivery systems usually contain more than two components. The existence and behavior of the percolation thresholds in ternary pharmaceutical dosage forms have been studied [39] employing mixtures of three substances with very different hydrophilicity and aqueous solubility (Polyvinylpyrrolidone (PVP) cross-linked, Eudragit RS-PM, and potassium chloride). 

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