RT Journal Article SR Electronic T1 Physiochemical Stability of Pharmaceutical Phosphate Buffer Solutions IV. Prevention of Precipitation in Parenteral Phosphate Solutions JF PDA Journal of Pharmaceutical Science and Technology JO PDA J Pharm Sci Technol FD Parenteral Drug Association (PDA) SP 210 OP 215 VO 36 IS 5 A1 Hasegawa, Kazue A1 Hashi, Kunio A1 Okada, Ryuzo YR 1982 UL http://journal.pda.org/content/36/5/210.abstract AB Complexing agents showing strong complexation for Ca(II) and Al(HI) were formulated for preparing physicochemically stable parenteral phosphate solutions. From results of a model experiment, a correlation was confirmed between precipitation in the phosphate buffer solutions and the amount of Ca(II) and/or Al(III) remaining in the solution. To prevent precipitation in parenteral phosphate solutions, EDTA was found to be effective in the range pH 5 to pH 9, carboxylic acids such as citric acid and maleic acid in acidic to neutral solutions, and pyrophosphate and lysine HCl in alkaline solutions. Further, elimination of the metals causing the precipitation from phosphate buffer was studied using ion-exchange resin treatment, and the phosphate buffer treated under the proposed conditions was found to be satisfactorily applicable to parenteral buffer solutions.