Propylene glycol solvent

NCO/OH ratio 1.05. DBTDL 0.004203 % Sn on binder solids. Solvent propylene glycol monoethyl ether acetate/xylene... 

Needles from dil ale, mp 193. Mi +28 (ale). Very sparingly sol in water. Soly (g/100 ml of solo) carbon tetrachloride 0.5 petr ether 0.1 ethyl acetate 1.1 acetone 0.6 chloroform 17.0 ethanol 19 benzene 0.9 isopropano] 15 Soly (g/100 ml of solvent) propylene glycol 0.1 dioxane 3.1 benzyl alcohol 8.1, On refluxing with methyl alcohol yields the 17-isopregnenolone, mp 172-173, [a] —140.5 (alcohol). 

Acetate, CaHHOy needles from alcohol, mp 149-151 . Mi +22 (alcohol). Soly (g/100 ml of soln) carbon tetrachloride 50. petr ether l.O, ethyl acetate 7.9 acetone 2.7 chloroform 55.0 ethanol 2.5 benzene 26.0 isopropanol 2.0. Soly (g/100 ml of solvent) propylene glycol 0.1 dioxane 20.2 benzyl alcohol It.] benzyl benzoate 9.1. 

The most significant concern with solvent exchange systems is the use of organic solvents. A study by Kranz et al. showed the PLGA and poly(lactide) dissolved in either NMP, DMSO, or 2-pyrrolidone were all myotoxic when injected intramuscularly (Kranz et al. 2001). Similar studies have produced similar results for candidate solvents propylene glycol and triacetin (Chandrashekar and Udupa 1996 Singh et al. 1997). Another hazard for many solvents used in these systems is the risk of hemolysis (Fu et al. 1987 Medlicott et al. 2000). 

Solvation due to chelate-type hydrogen-bond formation can also be observed in solutions of organic ligands made with non-aqueous solvents. Propylene glycol, for example, forms chelate-type hydrogen-bonds with deprotonated phenolate oxygen atoms in polypeptides, resulting in a decrease in their protonation constants [Bu 79, No 80] compared with those in water. 

The choice between an aqueous or non-aqueous solvent has already been explained in Sect. 9.1. Glycerol, propylene glycol and macrogol 400 are used as non-aqueous solvents. Propylene glycol is the most used. It is less hygroscopic than glycerol and less easily oxidised compared to macrogol 400. It has preservative properties in concentrations >15 %. 

Two vehicles have been proposed for diazepam enemas. Both are mixtures of water and co-solvents propylene glycol - ethanol 96 % - water (4+1+5, parts by volume, pH 4.8) and glycofurol - ethanol 96 % - water (5 + 1+4, parts by volume, pH 3.6). No significant difference in irritation score was observed with healthy volunteers [52]. 

Liquid, clear yellow NaCl content (%) 3.3-3.8 pH-value (30% in water at 25C) 5-7 Flash point C (closed cup) >100 Surface tension at 25C (dynes/cm) 1.00% in H20 Solvent Propylene glycol/water (ratio 60 40) TEGOPREN 7006 ... 

Some interest has been shown in solubilization of diuretics cyclopenthiazide, hydrochlorothiazide, hydroflumethazide and bendrofluazide [217] and fruse-mide [218,219]. The solubilities of the thiazide diuretics in water were not quoted. Micellar partition coefficients and the slopes of solubility-surfactant concentration plots were tabulated. At 35° C in polysorbate 80 the order of Pn, values was hydrochlorothiazide (50) < hydroflumethazide (106) < bendrofluazide (186) < cyclopenthiazide (195). For these and for frusemide, polysorbate 80 was the most efficient solubilizer. The solubility of frusemide in water is 65 xg ml at 35+0.5° C [218].Its normal dose is 10to40mg which must be accommodated in a liquid dose of 5 ml. As 20% w/v of polysorbate 80 solubilizes only 7.2 mg frusemide per ml, attempts were made to reduce the surfactant concentration by using co-solvents propylene glycol, ethyl alcohol and dimethylacetamide (DMA), but DMA at a concentration of 50 % in water can dissolve only 8.3 mg frusemide per ml. Polysorbate 80-DMA mixtures are compared with the co-solvent-water mixtures in Fig. 6.28. If the desired drug concentration is 10 mg ml 10%... 

Properties 200 Hazen max. cl. liq., odorless sol. in 2-propanol, ethanol, low aromatic solvent, propylene glycol, and wh. spirits disp. in water dens. 968 kg/m vise. 64 cs pour pt. -9 C cloud pt. > 47-53 C (1% aq.) flash pt. > 100 C pH 5-8 (1% aq.) HLB 11.6 surf, tension (Du Nouy, 0.1%) 27.0 mN/m 100% cone. Toxicology LD50 (oral, rat) > 500 mg/kg causes severe eye irritation si. irritating to skin may be harmful if swallowed TSCA listed Environmental Environmentally friendly Precaution Wear splash goggles and lab coat Hazardous Decomp. Prods. Heated to decomp., emits CO,... 

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