Single Use Pressure Sensors: For Single Use And Glass Bioreactor Monitoring And Control

In bioreactors, gases are introduced to the sterile vessel to both the liquid phase of the media and the gas phase in the head space to both supply the cells with the required oxygen and to control process conditions. The exhausted gas exits via a vent filter from the head space and it is important to use a filter of adequate size and construction to prevent it from clogging or becoming occluded with water. Also, pressure is used as a means of influencing mass transfer and mitigating contamination. However, an over pressure situation in a glass or single use bioreactor can occur at rather low pressures and a clogged vent filter on a bioreactor can cause a vessel to rupture, particularly on a single use bioreactor
bag, spilling the contents of the reactor and exposing the operators to unprocessed bulk creating a potentially hazardous situation. Classic stainless steel bioreactors typically have pressure monitoring and also a pressure relief function to prevent accidents. For single use bioreactors, PendoTECH single use pressure sensors are an ideal solution in this application for monitoring the pressure in the range of 1 psi and less.They are compatible with gamma irradiation up to 50 KGy so they can be placed on the bioreactor before it is gamma sterilized. Also, they are available pre-sterile so they can be aseptically installed after a glass bioreactor has been autoclaved. The sensors connect to the PendoTECH PressureMAT, which in addition to reading the sensors has 4-20 mA signal outputs, an RS-232 output, and alarm relay outputs. The relay can be tied directly to a tubing pinch valve to relieve an overpressure situation and even direct the air flow to a back-up filter so the process can continue.