Pipette Resistance
Pipette Resistance - Related Videos
06:35
Introduction to Serological Pipettes and Pipettors
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The serological pipette is frequently used in the laboratory for transferring milliliter volumes of liquid, from less than 1 ml to up to 50 ml. The pipettes can be sterile, plastic, and disposable or sterilizable, glass and reusable. Both kinds of pipettes use a pipet-aid, for the aspiration and dispensation of liquids. Different sizes of pipettes can be used with the same pipet-aid for a variety of experimental assays. For example, serological pipettes are useful for mixing chemical solutions...
05:30
Making Patch-pipettes and Sharp Electrodes with a Programmable Puller
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This video shows how to use a programmable puller to make patch pipettes and sharp electrodes for electrophysiology. The same procedure can be used to make a variety of glass tools, including injection needles.
05:12
Pressure-polishing Pipettes for Improved Patch-clamp Recording
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Cited by 13 •
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This is a guide to modifying the shape of glass micropipettes. Specifically, by using heat and air pressure the taper is widened without increasing the tip opening, leading to lower pipette resistance. This is critical to obtain low noise recordings of small cells but is useful in many applications.
08:46
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Drug resistance to targeted therapeutics is widespread and the need to identify mechanisms of resistance--prior to or following clinical onset--is critical for guiding alternative clinical management strategies. Here, we present a protocol to couple derivation of drug-resistant lines in vitro with sequencing to expedite discovery of these mechanisms.
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This manuscript demonstrates and discusses techniques used to survey pesticide susceptibility and detect resistance to contact and systemic pesticides in arthropod pests.
FAQs
Tip diameter and tip geometry strongly shape pipette resistance: smaller openings generally create narrower paths for current, so resistance rises. This makes tip dimensions a practical control variable during pipette selection. The resulting value helps determine whether a recording favors stability and low electrical noise or provides easier access to the cell.
The filling solution contributes to resistance through its ionic composition and concentration. Because current flows through the solution inside the glass pipette, changing these properties changes how readily current passes through the pipette. Researchers therefore treat solution composition and concentration as important experimental variables when establishing a resistance appropriate for neuronal recording.
Pipette resistance represents a compromise among several recording priorities. A selected value must support stable measurements while preserving suitable access to the neuron, limiting electrical noise, and allowing rapid membrane-potential or synaptic-current changes to be measured. The best choice consequently depends on the demands of the recording rather than on resistance alone.
The distance that current travels through the glass pipette contributes to the measured resistance, alongside the opening and filling solution. A longer current path can therefore alter the resistance even when other features appear similar. Accounting for this geometric factor improves consistency when comparing pipettes or interpreting differences between recording configurations.
Selection begins by matching resistance to the recording objective and the cell-access requirements. Researchers consider the tip dimensions, pipette geometry, filling solution, and glass path length, then choose a combination that balances stability, electrical noise, access, and response speed. This approach supports measurements suited to neuronal excitability, ion-channel activity, or synaptic transmission.
Researchers control the parameter by adjusting the physical and solution-related features that determine current flow. Relevant choices include the pipette tip opening and geometry, the filling solution's ionic composition and concentration, and the path length through the glass. Controlling these features helps establish a reproducible resistance before interpreting electrical recordings from neurons.
An appropriate value supports reliable measurements of neuronal excitability, ion-channel activity, and synaptic transmission. It also affects the ability to capture rapid changes in membrane potential or synaptic currents while maintaining recording stability and manageable noise. For this reason, pipette resistance is relevant across both patch-clamp and intracellular approaches to studying neuronal electrical behavior.