Figure 4.
Immobilization of oxidative coupling-modified pro-sfGFP. (a) Alkoxyamine-PEGA resin was synthesized using an NHS-activated Boc-aminooxyacetic acid. Subsequent deprotection using 50% TFA:DCM afforded the desired alkoxyamine functionalized resin. (b) Alkoxyamine-PEGA resin was incubated with pro-sfGFP and o-quinone-pro-sfGFP (OQP-sfGFP). Successful conjugation of the sfGFP to the alkoxyamine resin only occurred when the sfGFP had previously been modified through oxidative coupling. As an additional control, unmodified primary amine PEGA resin was incubated with OQP-sfGFP. No conjugation was observed. Bars denote 200 μm.