Potencial Goldman-GHK (simplif)
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The simplified Goldman-GHK potential calculator estimates the cell membrane potential (Vm) by considering the weighted influence of potassium (K⁺) and sodium (Na⁺) ions. It is a streamlined version of the Goldman-Hodgkin-Katz equation, accounting for relative membrane permeability to these ions and their intracellular and extracellular concentrations.
The formula uses a weighted average, where weights correspond to the relative permeability of K⁺ and Na⁺. Potassium permeability typically has a stronger impact on resting potential, while sodium plays a secondary role. The calculator ignores other ions (like Cl⁻) and assumes fixed permeability ratios in specific scenarios.
This tool is useful in cellular biophysics studies, particularly for estimating membrane potential under standardized conditions. It can aid in understanding processes like depolarization and repolarization in neurons, though results are approximate. Validation with more detailed methods is recommended for critical analyses.
Note that simplifications may underestimate or overestimate the actual potential if permeability or ionic concentrations vary significantly. Proper use requires prior knowledge of the physiological or experimental context of the cell being studied.
Frequently asked questions
Which ions are considered in this calculator?
The calculator focuses on potassium (K⁺) and sodium (Na⁺). Other ions like chloride (Cl⁻) are ignored for simplification.
How does the simplified version compare to the full equation?
The simplified version assumes fixed permeability ratios and ignores additional ions, while the full equation accounts for individual permeabilities of multiple ion species.
When should I use this tool instead of a more detailed model?
Use it for quick estimates under standard conditions, such as basic biophysics studies. Detailed models are required for critical analyses or complex variations.
Can I ignore other ions when using this calculator?
Yes, but results may be inaccurate if other ions have significant permeability in the studied cell.
Why might my results differ from lab measurements?
The tool is an approximation. Differences may arise from actual variations in ion permeability or concentrations outside the assumed context.