Noise-free patch clamping
No noise caused by pulsatile flow
Easily control flow rates below 1µL/min
Switch between vacuum and flow
Patch clamp: a short introduction
Patch clamp is an electrophysiology technique used to measure the ionic currents of isolated cells. It is especially useful to measure the activity of excitable cells, such neurons, cardiac cells and muscle fibers.
Briefly, a glass electrode containing the appropriate medium is placed at the cell membrane. Applying suction to the electrode will form a seal with the membrane. If the membrane remains intact, it is possible to record the activity of ion channels present in the patch of membrane that is in contact with the electrode. If the membrane is intentionally broken, whole-cell readings become possible, with the electrode acting as part of the cell. It is also possible to control the voltage or the current applied to the cell and record its responses, or detach a particular patch of membrane and study different interactions with the electrode.
Current patch clamping setups
Patch clamp is usually performed using peristaltic pumps. Researchers connect the glass electrode to the closed loop of the pump and fill it with a reading solution, using the motion of the rollers to create suction at the tip of the electrode and attach the cell membrane to it, which forms a GigaOhm seal.
This single-cell interaction is extremely sensitive to fluctuations in flow, and the seal can be lost due to the pulsatile nature of the peristaltic pump motion.
An improved protocol for patch clamping
Our mini pump can easily replace a peristaltic pump for patch clamping, while improving measurement accuracy by providing a much more stable and noise-free flow. Its simple design, with only one inlet, one outlet, and a screen that controls everything through a handle, takes care of all the fluidics and allows you to focus on biology. It is also easily adapted to different reservoir volumes, from Eppendorfs to 1 L bottles. Moreover, it is much more compact, being more convenient to place near the microscope.
Flow rates are easily controlled through its screen, going below 1ul/min, for localized measurements, or higher, for whole cell experiments. It is also possible to reverse the flow if the goal is to release the cell without breaking the membrane.
Setup
- Mini pump
- Reservoirs
- Glass electrode
The main aim of our setup is to change as little as possible from the conventional technique, with few adjustments to be done, while benefitting from considerable improvements. Thus, the mini pump was designed to simply replace the peristaltic pump, without the need to change or adapt anything else.
Patch clamping with the mini pump
Considering that the setup remains mostly the same as a conventional patch clamping experiment, here we focus on the the technical specifications of the mini pump:
Technical Specifications | |
Flow Rates | down to 1 µL/min |
Wetted material | Polyphenylsulfone (PPSU) or stainless steel |
Operating Temperature | 5-50 °C |
Maximum pressure | up to 500 mbar |
Mini pump applications
Some biological applications of our mini pump also include:
What is the working principle of the mini pump?
The mini pump has a piezoelectric mechanism.
Can the mini pump be used near/on top of a microscope stage?
Yes, the mini pump was designed to withstand high temperatures and humidity. It could be placed inside an incubator if needed.
What is the maximum flow rate that can be applied?
The system works well with the range of 0-5ml/min.
Funding and Support
The BIOPROS project results helped develop this instrument pack, with funding from the European Union’s Horizon research and innovation program under HORIZON-CL4-2021-DIGITAL-EMERGING-01-27, grant agreement no. 101070120.
