Practice question

In size exclusion chromatography, column volume is partitioned into distinct regions. Void volume Vo represents interstitial space between gel beads, inaccessible interior but traversed by excluded large molecules. Internal pore volume Vi is space within beads accessible to small molecules. Total bed volume Vt equals Vo + Vi + matrix volume. Exclusion volume is often synonymous with void volume, marking elution volume of completely excluded species. Gel volume refers to matrix itself. Distinguishing Vo clarifies early eluting peaks, allows calculation of Kd, and provides reference for determining molecular weight distribution and packing quality through calibration.