Hygroscopicity amorphous solids

A slight excess of a 10% sodium hydroxide solution was added to a solution of 23 grams of silver nitrate in 300 cc of water. The precipitated silver oxide was washed free of silver ion with distilled water. To a suspension of the silver oxide in 200 cc of water, a solution of 25 grams of (3-hydroxyphenyl)ethyl dimethylammonium iodide in 300 cc of water was added. The precipitate of silver iodide was removed by filtration and the filtrate concentrated to a volume of about 100 cc In vacuo. The remainder of the water was removed by lyophilization. (3-hydroxyphenyl)ethyl dimethylammonium hydroxide was obtained as a hygroscopic, amorphous solid,... 

Sodium salt, CggH N NaOgS, cilastatin sodium. Off-white to yellowish-white hygroscopic, amorphous solid. pKa, 2.0 pKa2 4.4 pKa, 9.2. Very sol in water, methanol. Combination with imipenem Primaxin, Zienam. 

H3C =CHCH2CH2C(SG1c) =N0S03H C11H19NO9S2 373.404 Isol. from rape seeds and many other Brassica spp. Highly hygroscopic, amorph. solid (as K salt). 

Dihydrostreptomycin sesquisulfate [5490-27-7] M 461.4, m 250 (dec), 255-265 (dec), [a]p -92.4 (c 1, H2O), pKgsJd)-- 9.5 (NMe), pKes,(2,3) 13.4 (guanidino). It crystallises from H2O with MeOH, -BuOH or methyl ethyl ketone. The crystals are not hygroscopic like the amorphous powder, however both forms are soluble in H2O but the amorphous solid is about 10 times more soluble than the crystals. The free base also crystallises from H20-Me2C0 and has [a]p -92° (aqueous solution pH 7.0). [Solomons and Regina Science 109 515 7949 Wolf et al. Science 109 515 7949 McGilveray and Rinehart J Am Chem Soc 87 4003 1956]. 

The dried product is a reddish brown, amorphous solid presenting a glistening surface upon fracture. The dry product is somewhat hygroscopic and is freely soluble in water to give a stable solution. The following paragraph gives an alternative preparation. 

The effect of relative humidity and temperature on the physical and structural properties of the 1 1 isopropanol solvatomorph of warfarin has been studied [58], Below the critical relative humidity of 60-68% the solid is not hygroscopic, but becomes deliquescent at higher values of relative humidity without exchange of water for isopropanol. Storage of the solvate-morph at elevated temperatures causes formation of an amorphous solid owing to loss of isopropanol, which may proceed through an intermediate crystalline phase. 

Drug molecules exist in various physical states, e.g. amorphous solid, crystalline solid, hygroscopic solid, liquid or gas. The physical state of drug molecules is an important factor in the formulation and delivery of drugs. 

A white, hygroscopic, crystalline powder or amorphous solid. M.p. 169° to 171°. 

PROP Very hygroscopic white when pure usually a gray-black or brownish amorphous solid. Light sensitive. D 4.7, mp 690°. IDLH 10 mg/m (as Ag). 

Nitroindene polymer was obtained by the nitration of polyindene (31- It is an amorphous solid of m.p. 230 0, and is insoluble in most solvents. Decomposition (explosion) temperature is above 360 C. It is sliglitly hygroscopic, taking 1.61% w ater from the atmosphere of 100% relative humidity. The Inler-nationaJ heat test at 75 C showed 1.1% loss of weight. A sample of 5 g evolved in vacuo 2 cm of gas in 48 hours. It was considered for use in U.S.. Army as a time fuse but was found to be too sensitive to impact. 

Properties White, amorphous solid tasteless odorless. D 1.25-1.31, hygroscopic. Stable when kept dry but deteriorates rapidly when damp. Soluble in dilute alkalies and concentrated acids almost insoluble in water precipitates from weak acid solutions. 

Cefazolin sodium is capable of existing in a number of crystalline modifications, but the amorphous state is produced by the lyophilization process [38]. The amorphous form retained its nature at relative humidities less than 56% but converted completely to the pentahydrate above 75% RH. Interestingly, the hygroscopicity of the amorphous form was essentially similar to that exhibited by the dehydrated monohydrate or dehydrated a-form. Lamotrigine mesylate was also found to exhibit a moisture-dependent amorphous-to-crystalline transition [39]. The transition was found to be independent of the presence of mannitol, whether the amorphous solid was produced by lyophilization or by spray-drying. 

Silver(II) fluoride is a gray-black, amorphous solid frequently showing a yellow bloom. It reacts very vigorously with water and is very hygroscopic, being converted to a greasy black mass by exposure to atmospheric moisture. 

Roy SD, Flyim GL (1989) SolubUity behavior of narcotic analgesics in aqueous media solubilities and dissociation constants of morphine, fentanyl and sufentanil. Pharm Res 6(2) 147-151 Rubinstein M, Colby RH (2003) Polymer physics. Oxford University Press, New York Rumondor ACF, Taylor LS (2010) Effect of polymer hygroscopicity on the phase behavior of amorphous solid dispersions in the presence of moisture. Mol Pharm 7(2) 477-490 Rumondor ACF, Marsac PJ, Stanford LA, Taylor LS (2009) Phase behavior of poly(vinylpyrrolidone) containing amorphous solid dispersions in the presence of moisture. Mol Pharm 6(5) 1492-1505... 

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