title: A Low-Noise Transimpedance Amplifier for BLM-Based Ion Channel Recording.
abstract: High-throughput screening (HTS) using ion channel recording is a powerful drug discovery technique in pharmacology. Ion channel recording with planar bilayer lipid membranes (BLM) is scalable and has very high sensitivity. A HTS system based on BLM ion channel recording faces three main challenges: (i) design of scalable microfluidic devices; (ii) design of compact ultra-low-noise transimpedance amplifiers able to detect currents in the pA range with bandwidth >10 kHz; (iii) design of compact, robust and scalable systems that integrate these two elements. This paper presents a low-noise transimpedance amplifier with integrated A/D conversion realized in CMOS 0.35 μm technology. The CMOS amplifier acquires currents in the range ±200 pA and ±20 nA, with 100 kHz bandwidth while dissipating 41 mW. An integrated digital offset compensation loop balances any voltage offsets from Ag/AgCl electrodes. The measured open-input input-referred noise current is as low as 4 fA/√Hz at ±200 pA range. The current amplifier is embedded in an integrated platform, together with a microfluidic device, for current recording from ion channels. Gramicidin-A, α-haemolysin and KcsA potassium channels have been used to prove both the platform and the current-to-digital converter.
authors.affiliation: Department of Electrical Electronic and Information Engineering G. Marconi, University of Bologna, Cesena Campus, Via Venezia 52, IT-47521 Cesena, Italy. marco.crescentini3@unibo.it.|Advanced Research Center on Electronic Systems (ARCES), University of Bologna, Cesena Campus, Via Venezia 52, IT-47521 Cesena, Italy. marco.crescentini3@unibo.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Crescentini
authors.affiliation: Center for Industrial Research (CIRI-ICT), University of Bologna, Via Venezia 52, IT-47521 Cesena, Italy. marco.bennati@unibo.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Bennati
authors.affiliation: Department of Electronic and Computer Science &amp; Institute for Life Science, University of Southampton, University Road, SO17 1BJ Southampton, UK. shimul.saha@mediwise.co.uk.
authors.forename: Shimul Chandra
authors.initials: SC
authors.lastname: Saha
authors.affiliation: Department of Electronic and Computer Science &amp; Institute for Life Science, University of Southampton, University Road, SO17 1BJ Southampton, UK. josip.ivica87@gmail.com.
authors.forename: Josip
authors.initials: J
authors.lastname: Ivica
authors.affiliation: Department of Electronic and Computer Science &amp; Institute for Life Science, University of Southampton, University Road, SO17 1BJ Southampton, UK. mdp@ecs.soton.ac.uk.
authors.forename: Maurits
authors.initials: M
authors.lastname: de Planque
authors.affiliation: Department of Electronic and Computer Science &amp; Institute for Life Science, University of Southampton, University Road, SO17 1BJ Southampton, UK. hm@ecs.soton.ac.uk.
authors.forename: Hywel
authors.initials: H
authors.lastname: Morgan
authors.affiliation: Department of Electrical Electronic and Information Engineering G. Marconi, University of Bologna, Cesena Campus, Via Venezia 52, IT-47521 Cesena, Italy. marco.tartagni@unibo.it.|Advanced Research Center on Electronic Systems (ARCES), University of Bologna, Cesena Campus, Via Venezia 52, IT-47521 Cesena, Italy. marco.tartagni@unibo.it.
authors.forename: Marco
authors.initials: M
authors.lastname: Tartagni
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D055808:Drug Discovery / Q000379:methods; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans; D007473:Ion Channels / Q000737:chemistry / Q000302:isolation & purification*; D056656:Lab-On-A-Chip Devices; D008051:Lipid Bilayers / Q000737:chemistry*
chemical_list: D007473:Ion Channels; D008051:Lipid Bilayers
keywords: bilayer lipid membranes; current sensing circuit; electrophysiology; ion channel recording; low-noise amplifier; low-noise current sensor; noise; transimpedance amplifier