DEVELOPMENT OF AN UPSET EARLY WARNING DEVICE (UEWD)TO PREDICT DEFLOCULATION EVENTS

摘要

This paper summarizes ongoing research leading to the development of an Upset Early WarningrnDevice (UEWD) designed to predict activated sludge deflocculation or biofilm detachmentrncaused by electrophilic chemicals into wastewaters. This biosensor concept is based on arnpreviously demonstrated response which shows that potassium is effluxed within seconds fromrnelectrophile-stressed bacterial cells, and that this potassium efflux correlates with activatedrnsludge deflocculation and biofilm detachment. The UEWD is a microfluidic device constructedrnof a polyethylene terephthalate glycol substratum and polyester lid, and incorporates in-channelrnposts to enhance bacterial immobilization in the channels. Escherichia coli K-12 is immobilizedrninto the channel, and changes in potassium levels in the wastewater flowing through the channelrnare detected using an ionophore/chromoionophore coupled optode. Preliminary results from anrnearly prototype of the device are presented.