Apparatus and methods for controlling insertion of a membrane channel into a membrane

Abstract

Apparatus and methods for controlling the insertion of a membrane channel into a membrane are disclosed. In one arrangement a first bath holds a first liquid in contact with a first surface of a membrane. A second bath holds a second liquid in contact with a second surface of the membrane. The membrane separates the first and second liquids. A first electrode contacts the first liquid. A second electrode contacts the second liquid. A driving unit applies a potential difference across the membrane via the first and second electrodes to promote insertion of a membrane channel into the membrane from the first liquid or the second liquid. A membrane voltage reduction unit is connected in series with the membrane. The driving unit applies a driving voltage across the membrane voltage reductionunit and the membrane, the driving voltage providing the potential difference across the membrane. The membrane voltage reduction unit is configured such that a reduction in resistance through the membrane caused by insertion of a membrane channel intrinsically increases a potential difference across the membrane voltage reduction unit thereby lowering the potential difference across the membrane.The lowering of the potential difference across the membrane is sufficient to prevent or reduce promotion of insertion of a further membrane channel.

Description

technical field [0001] The present invention relates to devices and methods for controlling the insertion of membrane channels into membranes. Background technique [0002] Channels formed across membranes can be used to sense molecular entities. Interactions between molecular entities and channels can result in characteristic modulations of the signal. By monitoring this signal, characteristic modulations can be detected, and thus molecular entities sensed. Various technologies have been proposed based on this principle, such as those disclosed in WO2008102120, WO2009035647, WO200079257, WO200142782 and WO2007057668. An example of this technique is the measurement of the electrical current signal due to the flow of ions through membrane channels. The membrane separates the two solutions, with membrane channels providing transport paths through the membrane between the solutions. The membranes are highly resistive such that the only route of transport between solutions i...

AI Technical Summary

Problems solved by technology

The downside of this approach is that it requires the user to observe the channel's current (or similar observable parameter like resistance) and manually react to changes in said parameter

While this is practical for single-channel recording, it is impractical when dealing with large arrays

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