Table 3.

Effects of protein concentration and use of slurry vs. on-column entrapment for Con A^a

Entrapment method and Con A concentration	Specific retention factor, MUM	Protein content (mg/g silica)	Protein content (μmol dimer/g silica)
Slurry method lOmg/mLCon A	13.4 (±1.2)	17.6 (±2.3)	0.33 (±0.04)
On-column method 1.0 mg/mLCon A	16.0 (±1.2)	21.0 (±2.6)	0.40 (±0.05)
On-column method 10 mg/mLCon A	34.7 (±2.9)	45.6 (±5.7)	0.86 (±0.11)

^aThe numbers in parentheses represent a range of ± 1 S.D., as obtained for a set of three injections. The specific retention factors were measured at 0.5 mL/min and 20 °C and have been corrected for any binding by MUM with the support in the absence of MUM. The protein content of each support was calculated from the specific retention factor for MUM by using a molar mass for the monomer of Con A of 26.5 kDa, the measured void volume of the column, the known packing density for the support (0.45 g/cm³), and an association equilibrium constant of 4.5 × 10⁵ M⁻¹ for MUM with Con A at pH 5.0 and 25 °C [28].