. Author manuscript; available in PMC: 2020 Sep 7.

Published in final edited form as: Analyst. 2019 Aug 2;144(17):5108–5116. doi: 10.1039/c9an01093a

Table 2.

Active antibodies/electrode using different immobilization strategies on screen printed carbon electrode using electrochemical assay and OPD enzyme activity assay (n=16 for electrochemical measurements and n=3 for OPD assay).

Immobilization Strategy	No. of Active antibodies/electrode × 10⁹
Immobilization Strategy	Electrochem. estimate	OPD Assay
AuNP/(EDC/NHSS)	2.56±0.20	2.94±0.11
rGO/(EDC/NHSS)	1.28±0.14	1.48±0.13
Chitosan/Glutaraldehyde	1.28±0.09	1.00±0.05
Direct antibody Adsorption	2.56±0.08	2.11±0.11
Protein A (Passive Adsorption)	0.26±0.01	0.23±0.01
Protein A on AuNP electrodes	5.13±0.36	5.86±0.41