Page 56 - Instrumental Analysis - Pharm D Clinical- 07-PA403
P. 56

Prof. Omayma Abdelrazak Amin             21

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    Chromatographic measurements of
          migration rates of solutes

    • Capacity Factor (k')

    • k'= (tR – tm)/tm = tR' /tm

    • The Selectivity Factor (α)

    • α = k'B/k'A = (tR')B/(tR')A  α>1

    • k'Bis the capacity factor of the more retained solute k'A is
    that for the more rapidly eluted solute

    ↑ α means more selective column &
                   more easier separation

    Prof. Omayma Abdelrazak Amin             22

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