Formulation development of Sodium citrate and Citric acid oral solution

Abstract

Introduction: Since the reconstituted powders for solution of sodium citrate and citric acid having an undesirable flavor caused the drawback of patient compliance for the treatment. However, powder dosage form is more stable than solutions and have a longer beyond used date. Thus, the formulations of reconstituted powder have been developed regarding the flavoring improvement and study their physical and chemical stability. In addition, the beyond used date and storage conditions have been performed. Materials and Methods: Various sweetening agents were used for improving the flavor of solution. Aspartame was used as a sweetening agent for further stability study. Powder of sodium citrate, citric acid and aspartame were separating contained in plastic bags and kept at 25°C/75% RH, 45°C/75% RH, and room temperature/75% RH for 4 months. The change in physical characters such as color and moisture content were determined. The remained contents of the citric acid and sodium citrate were carried out using acid-base titration and atomic absorption spectroscopy, respectively. Results: It was found that the appearance of sodium citrate powder was unchanged, but the moisture content and the percentage of sodium remained content were increased in all conditions for 4 months storage. The appearance of citric acid powder was slightly moist when keeping at 45°C/75% RH for 30 days. Aspartame powder was a pale yellow after keeping for 60 days. Conclusion: The desirable storage condition of reconstituted powders for solution of sodium citrate and citric acid was room temperature or 25°C with the humidity control. However, the beyond used date of the formulation could not be purposed. It was due to the overestimation of sodium content in reconstituted solution caused from the supersaturating solution of sodium chloride in which originates the 75% relative humidity condition. Therefore, the reconstituted powders for solution of sodium citrate and citric acid should be filling in the humidity control container. In addition, the microbiological test of reconstituted solution should be further study in order to verify the safety of the formulation.