Stability Studies of Amoxicillin and Gentamicin Injection in Intravenous Infusions

Context: Amoxicillinsodium and gentamicin sulfate are commonly antibiotics which used for infection treatment. In Indonesia, injection of antibiotics can be administered concurrently with intravenous infusion. Injection is mixed into the infusion bottle or directly injected into infusion tubing. Before use, mixed of antibiotics and intravenous infusion is usually stored in a refrigerator to maintain stability. Aims: The study was designed to examine the stability of amoxicillin sodium and gentamicin sulfate in intravenous infusions. Methods and Material: Each of Amoxicillin sodium and Gentamicin sulfate was mixed into the ringer’s dextrose infusion and ringer's lactate infusion at room temperature (270C) and cold temperature (40C) for 24 hours. The concentration of antibiotics were measured with Reversed-Phase High Performance Liquid Chromatography for 0, 1, 2, 3, 4, 5, 6, and 24 hours after antibiotics mixed to intravenous infusions. Results: Quantitative analysis was conducted by RP-HPLC, because this instrument give good separation of antibiotics from other components of intravenous infusion. The values of linearity, accuracy, precision, limit of detection and limit of quantification are fullfilled the criteria for HPLC validation. The stability of Amocixillin sodium influenced by the infusion type, temperature and time, while the stability of Gentamicin sulfate is only influenced by the infusion type. Conclusion: Amoxicillin sodium is more stable in ringer's lactate infusion, whereas Gentamicin sulfate is more stable in ringer's dextrose infusion.