Table 1 Sample preparation and processing of LFAs
|  | Streptavidin assay | Sandwich assay 0–20 nM | Clinical range assay |
|---|---|---|---|
QD-antibody conjugate | 10 µL CANdot-530-anti-CRP; 10 µL CANdot-610-anti-IL-6, both undiluted | 10 µL Qdot-525-anti-CRP; 10 µL Qdot-605-anti-IL-6, both undiluted | 10 µL Qdot-525-anti-CRP, diluted 1:1 with 0.3 µg/mL anti-CRP (mouse); 5 µL Qdot-605-anti-IL-6, undiluted |
LFA-test strips | Test line, polystreptavidin; control line, anti-mouse secondary antibody | Test line, anti CRP (rabbit)/anti IL-6 (goat); control line, anti-mouse- secondary antibody; membrane CN95 | Test line, anti CRP (rabbit)/anti IL-6 (goat); control line, anti-mouse- secondary antibody; membrane CN150 |
Sample composition | 20 µL QD-conjugate 10 µL CRP/IL-6 (biotinylated), 0–20 nM in 1× PBS (pH 7.4) 70 µL running buffer | 20 µL QD conjugate 10 µL CRP/IL-6, 0–20 nM in 1× PBS (1% serum, pH 7.4) 70 µL running buffer | 15 µL QD conjugate 50 µL CRP (0–1000 nM)/IL-6, (0–60 pM) in 1× PBS (10% serum, pH 7.4) 55 µL running buffer |
Assay time | 1 min incubation of sample mix 10 min run time 10 min drying Imaging ≤ 2 min | 1 min incubation of sample mix 10 min run time 10 min drying Imaging ≤ 2 min | 1 min incubation of sample mix 20 min run time 10 min drying Imaging ≤ 2 min |