Flow rate influence of the peristaltic-based pumps on the QCM sensor

The liquid injection is one of the crucial roles in the used of QCM sensors in a liquid application. Liquid sample injection should be controlled. The injection of the liquid sample to the sensor surface must be controlled in term of its volume as well as its flow rate. A syringe pump injection system for a single shot sample injection has been developed. However, the system lacked a continuous sample injection. In this study, a peristaltic-based pump has been developed. A motor stepper and appropriate motor driver allowed the system to works from a micro-step to full step speed. The injection system allowed one to control the volume as well as the flow rate. The developed system was able to feed a liquid sample to the QCM sensor surface with a wide range of flow rate. It was observed that the flow rate injection affected the QCM sensor to respond. Careful selection of the liquid flow rate was required to avoid an unintended effect on the QCM sensor. Using the developed system, we show that a minimum effect on the QCM sensor respond caused by the flow rate of the liquid injection can be achieved.