Fluorescence Anisotropy Calculator

Calculate fluorescence anisotropy and polarization for molecular dynamics studies

Intensity Measurements

Correction for instrument polarization bias

Physical Parameters

Anisotropy (r)

0.1818

Polarization (P)

0.2500

Calculated Parameters

Total Intensity110,000
Rotational Corr. Time (θ)3.434 ns
Theoretical Anisotropy0.1848
Depolarization Factor2.16

Equations

r = (I∥ - GI⊥) / (I∥ + 2GI⊥)

P = (I∥ - GI⊥) / (I∥ + GI⊥)

r = r₀ / (1 + τ/θ)

Interpretation

Intermediate anisotropy - partial binding or medium-sized complex

About Fluorescence Anisotropy

Fluorescence anisotropy measures the rotational diffusion of fluorescent molecules, which is related to molecular size and binding state.

  • Free ligand: Fast rotation, low anisotropy (r ~ 0.02-0.05)
  • Bound to protein: Slow rotation, high anisotropy (r ~ 0.15-0.35)
  • Applications: Binding assays, drug screening, protein-protein interactions
  • Limiting anisotropy (r₀): Typically 0.3-0.4 for most fluorophores
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Editorial Note

MyCalcBuddy Editorial Team

This page is maintained as an educational calculator reference.

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Formula Source: Standard Mathematical References

by Various

🔄Last reviewed: May 2026
✓Formula checks are based on standard references and internal QA review.