In Fig. 3b a calibration curve obtained with free HRP in solution is
shown, in which the determined activity rate k [min1
]=(DA414/
Dt) is plotted versus the HRP concentration CHRP. The activity assay
was then applied to the PCs with attached HRP after three times
magnetic purification (HRP/Ab-PCs), as well as to the supernatants
containing the unbound HRP after the three subsequent washing
steps (w1 - w3). The spectroscopic data DA414 (A414(t) A414(0))
are plotted in Fig. 3c. The corresponding activity rates k [min1
]
= (DA414/Dt) are enlisted in Table 1. Note that the initial HRP concentration
in the HRP/Ab-PC mixture, before magnetic separation
was CHRP = 5 lg/mL. According to the calibration curve shown in
Fig. 3b a corresponding concentration of free HRP possesses the
activity rate k = 0.125 ± 0.003 min