Ligand Depletion Mass Balance Residual Tool

Description

Return ligand balance residual from supplied occupancy.

Enzyme and binding models relate supplied rates, concentrations and active-site conventions under specific assumptions. A local apparent parameter, turnover or occupancy term does not identify an inhibition mechanism, fit a kinetic model or establish a validated assay.

Return ligand balance residual from supplied occupancy.

When to use this tool

Use Ligand Depletion Mass Balance Residual when evaluating the stated enzyme, binding, dilution or rate-basis term.

How to use the tool and how it works

Enter totalLigand, freeLigand, totalSites, occupancy. Use the units and conventions below.
Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
Read boundLigand, accountedLigand, residual. Use the output convention below.

Return ligand balance residual from supplied occupancy. Require nonnegative total/free ligand and totalSites, occupancy in [0,1]; bound = sites*occupancy, accounted = free+bound, residual = total-accounted.^[1]

Input field	Meaning and units	Accepted input
totalLigand	Total Ligand	Required. Finite number; minimum 0.
freeLigand	Free Ligand	Required. Finite number; minimum 0.
totalSites	Total Sites	Required. Finite number; minimum 0.
occupancy	Occupancy	Required. Finite number; minimum 0; maximum 1.

Output field	Interpretation	Returned shape
boundLigand	Bound Ligand	Required. Finite number.
accountedLigand	Accounted Ligand	Required. Finite number.
residual	Signed difference in the direction stated above, with matching units.	Required. Finite number.

json

{
  "input": {
    "totalLigand": 10,
    "freeLigand": 4,
    "totalSites": 8,
    "occupancy": 0.75
  },
  "output": {
    "boundLigand": 6,
    "accountedLigand": 10,
    "residual": 0
  }
}

Limitations and assumptions

All quantities share an amount or concentration basis; occupancy, depletion equilibrium and binding stoichiometry are not solved.
Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.

Alternative or Complementary methods

Use calibrated observations and a complete suitable kinetic/assay model, including substrate, active-site and stoichiometric conventions, for biochemical inference.

References

Calculation and input contract: biochemistry/ligand-depletion-mass-balance-residual — tool.io

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