Highly Sensitive Biosensor for Protein Analysis based on Amplification Strategy
Calmodulin (CaM) is an essential protein that participates in many intracellular activities, and it has been found
to intimately associate with cancer diagnosis and treatment. In this paper, we report a highly sensitive electrochemical
immunosensor for the detection of CaM with based multifunctional biolabel. Reduced grapheme oxide (rGO)/gold popcorn
nanoparticles (GPCs) with high conductivity and large surface area were employed as the sensing matrix of the
immunosensor to immobilize CaM. Multifunctional biolabel (HRP-GMC-Ab1) was introduced not only to specifically
recognize the captured CaM, but also to provide a large amount of HRP for the catalytic current output. Attributed to this
strategy, enhanced attached amount of HRP could be obtained and resulted in amplified electrochemical signals. Analytical
results show that this immune sensor exhibited good performance with high sensitivity and stability, and could be extend to
other important protein analysis schemes.
Index Terms - Biosensor, Cancer, electrochemical, Protein Biomarker.