Porod invariant
The Porod invariant, is the integral of the area of the Kratky curve:
- Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle I_{\mathrm{total}}= \int_0^{\infty} I(q) q^2 \mathrm{d}q }
This quantity is independent of concentration, and is proportional to molecular mass. In principle, one can use this method to measure MW. However, the MWs determined in this way are often inaccurate (incorrect background subtraction, voids, intrinsic flexibility, etc.).
