Fig. 8

Detection of as-APF in spiked urine. Control urine was mixed 1:1 with as-APF stock (200 μM) solution. Various dilutions of this mixture in SPR running buffer were prepared and injected over a CM5 chip surface immobilized with CKAP4_127–360 by amine-coupling on the Fc2 channel. Fc1 channel was similarly treated but without CKAP4, as the reference. Final concentrations of as-APF were 40 μM (a), 20 μM (b), 5 μM (c), and 1.25 μM (d). Sensorgrams were corrected for background interference from urinary constituents by subtracting the RU traces resulting from unspiked urine injections from the RU traces resulting from the corresponding urine dilutions with spiked as-APF, and re-plotted after subtracting the RU trace from the reference (Fc1) channel