Novel Rapid Protein Coating Technique for Silicon Photonic Biosensor to Improve Surface Morphology and Increase Bioreceptor Density

Tags

Top Highlights

• were coupled with

• 2.1. Conventional APTES-GA and EDC-NHS Coating Techniques

• hydrolysis of ethoxy (–C 2H 5) groups from APTES, leading to the formation of silanols (Si–OH)

• both aldehydes of some GA molecules may bind with APTES,

• This produced Caro’s acid (H2SO5), which can cause dissociation and generate a hydroxyl radical (OH*) to produce hydroxyl groups (–OH) by a hydroxylation process

• the hydroxylated silicon surface was immersed in APTES solution (2% APTES in 95% ethanol) for 1 h at 68 °C

• Each protein was conjugated with 0.7 mg/mL of EDC and 0.6 mg/mL of NHS in the activation buffer (0.1 M MES, 0.5 M NaCl, pH 6.0) for 15 min at room temperature (premixing)

• Element composition after each step of GOx coating using (a) APTES-GA technique and (b) APTES-(EDC/NHS) technique.