Dynamic behavior analysis of drug delivery devices using a dynamic gravimetric method

The calibration of drug delivery devices is essential for accurate dose control. In this study, drug delivery devices, namely infusion and syringe pumps, were assessed using a dynamic gravimetric method. The flow rates caused by the syringe pump, infusion pump, and pressure-based pump were measured at various flow rates (0.5-60 mL/h) by simultaneously using a dynamic gravimetric method and flow meter. The measurement error uncertainty of the pumps were obtained using the dynamic gravimetric calibration method. The pulsation period and amplitude were obtained with respect to the flow rate to analyze the pulsating flow of the syringe pump and infusion pump. The pump error increased in the following order: the pressure-based pump, syringe pump, and infusion pump based on the flow rate. The measurement error uncertainty of the syringe pump increased slightly when the flow rate decreased, whereas the infusion pump exhibited significant increases in the error and uncertainty when the flow rate decreased. The flow stability of the pulsating flow from each pump was analyzed according to the flow rate. Thus, we discussed the characteristics of the pulsating flow from each drug delivery device. We confirmed that the pumps had different flow stability, error, and measurement uncertainty because of their different working principles.