Assembly of the Test Strip
An absorbent pad was sealed using a sample pad blocking solution (PBS
solution containing 0.5% PVP, 0.5% Tween-20, 2% PEG20000, 1% BSA)
for 0.5–1 h and preserved in a desiccant-containing paper bag. A
conjugate pad was placed in a conjugate pad blocking solution (0.75%
trehalose, 0.5% sucrose, 2% BSA, 0.5% Tween-20, 0.5% TritonX-100 in
PBS); then, the conjugate pad was sprayed with a colloidal gold solution
and placed in an oven at 37 °C for 3 h. After complete drying, tweezers
were used to gently place the coated conjugate pad in a
desiccant-containing paper bag and stored at room temperature.
Subsequently, the conjugate pad was sprayed with a 1:1 mixture of p30
and p72 protein monoclonal antibodies (1 mg/mL) on the control line of
the nitrocellulose membrane. Additionally, p72 (0.5 mg/mL) and p30
proteins (0.1 mg/mL) were sprayed on test lines 1 (T1) and 2 (T2) of the
nitrocellulose membrane, respectively.