TY  - JOUR
A1  - Mak, Wing Cheung
A1  - Cheung, Kwan Yee
A1  - Trau, Dieter
A1  - Warsinke, Axel
A1  - Scheller, Frieder W.
A1  - Renneberg, Reinhard
T1  - Electrochemical bioassay utilizing encapsulated electrochemical active microcrystal biolabels
N2  - A new approach to perform electrochemical immunoassay based on the utilization of encapsulated microcrystal was developed. The microcrystal labels create a "supernova effect" upon exposure to a desired releasing agent. The microcrystal cores dissolve, and large amounts of signal-generating molecules diffuse across the capsule wall into the outer environment. Layer-by-Layer (LbL) technology was employed for the encapsulation of electrochemical signal- generating microcrystals (ferrocene microcrystals). The encapsulated microcrystals were conjugated with antibody molecules through the adsorption process. The biofunctionalized microcrystals were utilized as a probe for immunoassays. The microcrystal-based label system provided a high-signal molecule to antibody (SIP) ratio of 10(4)-10(5). Microcrystal biolabels with different antibody surface coverage (1.60-5.05 mg m(-2)) were subjected to a solid-phase immunoassay for the detection of mouse immunoglobulin G (M-IgG) molecules. The microcrystal-based immunoassay for the detection of M-IgG performed with microcrystals having antibody surface coverage of 5.05 mg m(-2) showed a sensitivity of 3.93 nA  g(- 1) L-1 with a detection limit of 2.82  g L-1
Y1  - 2005
SN  - 0003-2700
ER  -