How many antibody molecules per agarose bead?

How many antibody molecules per agarose bead?

By Douglas Hayworth

Quick! Guess how many molecules of antibody (IgG) can be bound per bead of Protein A/G agarose resin:

  • 100
  • 10,000
  • 1,000,000
  • 1,000,000,000

How many agarose beads are in a 1-milliliter affinity purification column?

  • 150
  • 15,000
  • 1,500,000
  • 1,500,000,000

At one time or another, most life scientists have used beaded agarose affinity resins to immunoprecipitate, enrich or purify proteins or nucleic acids for detection in polyacrylamide gels, Western blots and the like. Because we are concerned primarily with purification yield in terms of micromolar concentration or total micrograms, we seldom stop to conceptualize the relative sizes and numbers of molecules involved in these affinity purification methods.

In a new article, Douglas Hayworth and Greg Hermanson use simple calculations to estimate the average relative sizes, volumes and numbers of molecules involved in typical affinity purification procedures with beaded agarose supports. Read the article to check your guesses.


Read the Article:

Calculate the number of immobilized proteins per bead of agarose affinity supports

Calculate the number of immobilized proteins per bead of agarose affinity supports