Water toxicity detection through perfusion and monitoring of living cells on a microfluidic chip Fang Li, Ph.D. Department of Mechanical Engineering New York Institute of Technology 1

Introduction The needs for fast, rapid, accurate, portable and low- cost toxicity detection method to provide affordable water security –Climate change, rapid urbanization, increasing population extensive agriculture, etc. –Periodic and extensive testing at key points of the water infrastructure –Current method: long processing times and high cost Solution: Cell – based biosensors (CBB) –Be able to detect a broad range of analytes in a single assay –Relate the measurement data to cell pathology and physiology –Fast and low cost 12/18/20152 Highly sensitive, robust CBB system to fast detect a broad range of toxicants are needed!

Introduction Performance (sensitivity, response time, reliability) of CBB to toxicants dependent on –Cell layer (cell type, cell seeding density) –Sensing techniques (sensing methods, data analysis) –Fluidic delivery method 12/18/20153

Our Method: Electrical cell- substrate impedance sensing 12/18/20154

5 Results: BAECs v.s. RFPECs

6 Our method: microfluidic device integrated on ECIS sensor

7 Results: microfluidic device integrated on ECIS sensor

8 Results: microfluidic closed chamber v.s. open well

9 Results: toxicity testing- closed chambers v.s. open wells Phenol Aldicarb

10 Results: toxicity testing- closed chambers v.s. open wells Ammonia Nicotine

11 Results: toxicity testing- closed chambers v.s. open wells

12 Discussion BAEC line is suitable for impedance measurements and toxicity testing –Firm attachment, quickly to form a monolayer, high impedance value Closed cell culture chambers over the open culturing wells –Barriers in microfluidic device significantly decrease the shear stress and creates more uniform flow velocity –Significantly shorten the response time of the ECIS sensors, especially for low concentration of toxicant short diffusion distances Uniform medium perfusion volatile nature of the toxicants

On-going work to improve sensor sensitivity 13 Develop a mathematical model to describe the relation between measured impedance spectrum and cell electrical properties and morphology –extract cellular parameters: cell membrane capacitance, cell-cell junction, cell-substrate distance, etc. –Improve sensor sensitivity to a broad range of toxic chemicals –Correlate cellular parameters to toxicants level and type Combine multiple sensing techniques: impendence and acoustic wave sensor Apply nanomaterials on top surface of sensors to improve sensor’s sensitivity

CBB toxicity sensors for FEW system Provide water safety data every 3-4 hours. –integrated to the water quality WSNs and provide information on water safety and toxicity in drinking water infrastructures –serve as an early warning system for FEW management. –evaluate and optimize the sensor network design –evaluate the effectiveness of FEW management system in terms of drinking water safety. 14

Questions? 15