What is the exclusion limit of Sephadex G-50?
Sephadex is cross-linked dextran gel classified by G-value indicating degree of cross-linking and porosity. G-50 denotes moderate cross-linking with fractionation range for globular proteins approximately 1,500 to 30,000 daltons. Molecules larger than 30,000 daltons are excluded, eluting at void volume; smaller molecules penetrate and are retarded. Exclusion limit defines upper molecular weight threshold. Different grades like G-25, G-75, G-100 offer varying ranges. Knowledge of exclusion limits guides selection for desalting, buffer exchange, or separation of peptides from proteins, ensuring
Ref: NCERT Biology Class XII Principles on Klenow fill-in labeling, Lehninger Chapter 9 DNA cloning techniques, and Molecular Cloning by Sambrook Chapter 10 documenting end-labeling of cohesive termini.