EDR4
| EDR4 | |
|---|---|
 Unit e4-00044 in its 3D-printed bracket above the flow cell | |
| Manufacturer | Elements srl |
| Type | Four-channel patch-clamp amplifier |
| Connectivity | USB |
| Power | USB |
| Serial | e4-00044 |
| Hardware | Version 4.8, firmware 129 |
| Voltage | ±511 mV in steps of 0.0625 mV |
| Sampling | Up to 200 kHz |
The EDR4 is a four-channel patch-clamp amplifier made by the Italian company Elements srl and used by Molecular Reality Corporation to measure the current through the pore on its laboratory bench. One unit, serial number e4-00044, has made every recording of real data on the company's live molecular stream and in its Streams archive. The company's guide calls it "the laboratory's ear".[1]
The amplifier holds a set voltage across a membrane and measures the current that flows through the hole in it, which for a nanopore is a few picoamperes to a few nanoamperes. It is small enough to be powered over USB, and on the company's bench it hangs in a 3D-printed bracket directly above the flow cell. Its first channel is read 200,000 times a second.[1][2]
Name
Strictly, EDR4 is the name of the recording software that Elements supplies with its amplifiers. Nanion Technologies states that its Orbit 16 TC instrument "comes with the EDR4 software developed by our partner Elements S.R.L. (Italy)".[3] Molecular Reality uses the name for the hardware. Its shelf of laboratory provisions lists the unit as "Elements EDR4 (e4-00044)" and the stream page's status line reads "EDR4 e4-00044".[2] The guide explains the second part of the label: "The tag e4 00044 is the serial number of the unit now doing the streaming, so when you see that label on the archive, you know which instrument made that data."[1] Every recording of real data in the archive carries it.[4]
How a patch-clamp amplifier works
The patch clamp was developed to record the current through single ion channels in the membranes of living cells. Erwin Neher and Bert Sakmann published the first such recordings in 1976, from frog muscle fibers, and shared the 1991 Nobel Prize in Physiology or Medicine for the method.[5] A single open channel passes a few picoamperes, about the current through a small nanopore, and the instruments built for one problem suit the other.[6]
The amplifier "clamps" the voltage: it applies a chosen potential between two electrodes, one on each side of the membrane, and feeds back whatever current is needed to keep it there. That current is the measurement. At the input a transimpedance amplifier turns it into a voltage, which is digitized and sent to a computer. The guide describes the arrangement as "the instrument that applies the voltage and hears the current".[1] Any resistor in that input stage adds a thermal noise current of over a bandwidth , so a recording that is fast enough to catch short events is also noisier, and the guide's summary is that "filtering smears the fast events you came to see."[1][a]
The unit at Molecular Reality
The company's records give the unit as hardware version 4.8 with firmware 129. It has four independent current channels and one channel that sets the voltage, over a range of ±511 millivolts in steps of 0.0625 mV, so a sweep from one end of the range to the other passes through about 16,000 settings. The company runs channel 0 "at the device's maximum sampling rate", recording every sample of both the current and the applied voltage as a 16-bit integer, and sends "a 20 Hz feature stream for the live view". The same entry notes that a "Zapper (membrane break-in) and digital offset compensation are available", and calls the amplifier "the first hardcoded device on Epic Quest Bio and the source of kemmishtree's streams."[2]
Elements' library handles the conversation with the hardware. On a laptop at the bench, a short program in C++ written by the company reads the samples through it and forwards them to the company's server, which passes them to the stream page and the archive.[7] A three-position voltage control on the company's side maps to minus 500, zero and plus 500 millivolts, inside the amplifier's range. When no amplifier is connected, a simulator stands in and answers commands in its place.[7]
Before the stream existed the amplifier lived in a shielded box. A caption on the company's site described the box as "from the great folks at elements-ic.com" and "one of the two best Faraday cages we've used", and gave its status: "sitting near Kemmishtree's desk, with a four channel amplifier inside, the first instrument we'll stream here."[7]
Sampling rate
The guide gives the sampling rate as 200 kHz, "a measurement every five microseconds", and every recording in the archive lists 200,000 samples a second.[1][4] At that rate a signal can contain frequencies up to 100 kHz, half the sampling rate, before it is misread. A molecule that blocks the pore for 50 microseconds is caught in ten samples. The live page shows far less than is recorded: each of its twenty updates a second summarizes about 10,000 samples, and the full-rate data can be seen only in the archive's viewer.[2][b]
Place in the company's hardware
It is the first commercial amplifier the company has streamed. Earlier work used other equipment: the first sliding occlusion runs, in 2015 and 2016, were read on a benchtop picoammeter.[7] In 2020 and 2021 the demonpore 64 carried the company's own Teabiscuits electronics, specified for picoampere to nanoampere currents at 125 kHz.[7] Molecular Reality's open design, the MR1 Nanopore Reader, samples at 100 kHz with an amplifier built around an LMP7721 chip, and had not been built when it was released in October 2026.[8] In early 2026 the company's list of provisions also carried an "eONE amplifier", with the note "One of two eONE amplifiers I have on hand".[7]
The DNA barcode recordings published by Bell and Keyser in 2016, which the company has used to train its machine-learning models, were made on an Axopatch, a bench amplifier from Molecular Devices of the kind described in the article Axopatch 200B.[7] The EDR4 runs from a USB cable. Its first end-to-end test with a flow cell was run in Arizona on the evening of May 7, 2026.[9]
See also
Notes
- ^ Keeping the wires between the electrodes and the amplifier short lowers their capacitance and the interference they collect, both of which add noise at high bandwidth. That is one reason the amplifier hangs directly over the flow cell.
- ^ An early technical note on the setup, written while the relay was being built in 2026, recorded the rate actually in use as about 1.25 kHz, with 200 kHz available. By the time the archive opened on June 10, 2026, every recording was made at 200 kHz.[7]
References
- ^ a b c d e f "Keltar's Field Guide to Molecular Reality". Molecular Reality Corporation. August 2026.
- ^ a b c d "Molecular Reality Corporation: live stream and provisions". Molecular Reality Corporation. Retrieved October 25, 2026.
- ^ "Software". Orbit 16 TC. Nanion Technologies. Retrieved October 25, 2026.
- ^ a b "Streams". Epic Quest Bio. Molecular Reality Corporation. Retrieved October 25, 2026.
- ^ Neher, E.; Sakmann, B. (1976). "Single-channel currents recorded from membrane of denervated frog muscle fibres". Nature 260 (5554): 799. doi:10.1038/260799a0.
- ^ Lenora Ashgrove (July 29, 2026). "Nineteen Billion Ions a Second, Live on the Internet". Signal & Noise.
- ^ a b c d e f g h "Company records". Molecular Reality Corporation. October 2026.
- ^ "MR1 Nanopore Reader". GitHub. October 16, 2026.
- ^ Dot Kimberley (May 12, 2026). "Local Bench Streams Salt Water to the World". The Coulter Courier.