Parallel recording of neurotransmitters release from chromaffin cells using a 10×10 CMOS IC potentiostat array with on-chip working electrodes

Abstract

Neurotransmitter release is modulated by many drugs and molecular manipulations. We present an active CMOS-based electrochemical biosensor array with high throughput capability (100 electrodes) for on-chip amperometric measurement of neurotransmitter release. The high-throughput of the biosensor array will accelerate the data collection needed to determine statistical significance of changes produced under varying conditions, from several weeks to a few hours. The biosensor is designed and fabricated using a combination of CMOS integrated circuit (IC) technology and a photolithography process to incorporate platinum working electrodes on-chip. We demonstrate the operation of an electrode array with integrated high-gain potentiostats and output time-division multiplexing with minimum dead time for readout. The on-chip working electrodes are patterned by conformal deposition of Pt and lift-off photolithography. The conformal deposition method protects the underlying electronic circuits from contact with the electrolyte that covers the electrode array during measurement. The biosensor was validated by simultaneous measurement of amperometric currents from 100 electrodes in response to dopamine injection, which revealed the time course of dopamine diffusion along the surface of the biosensor array. The biosensor simultaneously recorded neurotransmitter release successfully from multiple individual living chromaffin cells. The biosensor was capable of resolving small and fast amperometric spikes reporting release from individual vesicle secretions. We anticipate that this device will accelerate the characterization of the modulation of neurotransmitter secretion from neuronal and endocrine cells by pharmacological and molecular manipulations of the cells.

A Bidirectional-Current CMOS Potentiostat for Fast-Scan Cyclic Voltammetry Detector Arrays

“…The tip of the carbon fiber was entirely coated with wax and then cut such that only the circular area at the end of the cut fiber was exposed as the working electrode. The area of such a CFM is similar to that of onchip electrodes after post-fabrication [11], [13], which also will be fabricated in the future on the FSCV chip described here. The CFM was immersed into a petri dish filled with a buffer solution containing 140 mM NaCl, 5 mM KCl, 5 mM CaCl 2 , 1 mM MgCl 2 , and 10 mM HEPES/NaOH pH 7.3.…”

“…The detector array provides a five-fold increase in temporal resolution over the unidirectional-current detector array we reported previously in [11], [13]. …”

Microchemistry- and MEMS-based Integrated Electrochemical Devices for Bioassay Applications

“…To overcome this problem and incorporate more sensors into a chip-based device, semiconductor technology has been employed. [59][60][61][62][63][64][65][66][67][68] For instance, Lindau and colleagues reported the development of a complementary metal oxide semiconductor (CMOS)-based chip containing 10 © 10 microelectrodes for use in the detection of dopamine. 68 We developed an LSI-based amperometric sensor for electrochemical imaging, [69][70][71][72] designated the Bio-LSI system, first reported by Inoue et al 69 The Bio-LSI system is based on CMOS technology and provides higher temporal resolution for the detection of electrochemical species at different locations on the chip.…”

Electrochemical Imaging for Single-cell Analysis of Cell Adhesion Using a Collagen-coated Large-scale Integration (LSI)-based Amperometric Device

“…7 Kim et al recently reported a complementary metal oxide semiconductor (CMOS)-based electrode array containing 100 electrodes for the simultaneous recording of exocytotic events from cells. 8 We previously developed a Bio-LSI (large-scale integration) device for the characterization of biomaterials that comprises 400 electrochemical sensors with a pitch of 250 µm arranged to form a LSI-based amperometric device. [9][10][11][12][13][14] The device is based on CMOS technology and an operational amplifier is incorporated into each sensor.…”