CMOS Imaging of Pin-Printed Xerogel-Based Luminescent Sensor Microarrays.
We present the design and implementation of a luminescence-based miniaturized multisensor system using pin-printed xerogel materials which act as host media for chemical recognition elements. We developed a CMOS imager integrated circuit (IC) to image the luminescence response of the xerogel-based sensor array. The imager IC uses a 26 × 20 (520 elements) array of active pixel sensors and each active pixel includes a high-gain phototransistor to convert the detected optical signals into electrical currents. The imager includes a correlated double sampling circuit and pixel address/digital control circuit; the image data is read-out as coded serial signal. The sensor system uses a light-emitting diode (LED) to excite the target analyte responsive luminophores doped within discrete xerogel-based sensor elements. As a prototype, we developed a 4 × 4 (16 elements) array of oxygen (O2) sensors. Each group of 4 sensor elements in the array (arranged in a row) is designed to provide a different and specific sensitivity to the target gaseous O2concentration. This property of multiple sensitivities is achieved by using a strategic mix of two oxygen sensitive luminophores ([Ru(dpp)3]2+and ([Ru(bpy)3]2+) in each pin-printed xerogel sensor element. The CMOS imager consumes an average power of 8 mW operating at 1 kHz sampling frequency driven at 5 V. The developed prototype system demonstrates a low cost and miniaturized luminescence multisensor system.
Department of Electrical and Computer Engineering, McGill University, Montreal, QB, H3A2A7 Canada.
Lei
L
Yao
Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260 USA.
Ka Yi
KY
Yung
Department of Electrical and Computer Engineering, McGill University, Montreal, QB, H3A2A7 Canada.
Rifat
R
Khan
Department of Electrical and Computer Engineering, McGill University, Montreal, QB, H3A2A7 Canada.
Vamsy P
VP
Chodavarapu
Department of Chemistry, University at Buffalo, The State University of New York, Buffalo, NY 14260 USA.
Frank V
FV
Bright
CMOS imager; luminescence; multi sensor system; optical sensors; oxygen sensors; pin-printing; sensor microarrays; xerogel