We have fabricated and tested GaN nanowire bioFETs utilizing amine-reactive surface chemistry, and taken electrical measurements at various stages throughout the functionalization process. Test structures were fabricated with nanowires grown on Si with MBE. GaN nanowires were released into a suspension via ultrasonic agitation, pipetted onto pre-deposited Ti pads and aligned with dieletrophoresis, forming a two-terminal bridge structure. A capping layer of Ti/Al pins the wires to the substrate and forms two conformal electrical contacts. From this point, the most critical requirements for nanowire-based bioFET fabrication are electrical stability and effective surface functionalization. We have demonstrated the electrical stability of these two-terminal GaN nanowire bridge structures when submerged in solutions of pH 1, 4, 7 and 10. We attribute this stability to the inert, chemically robust GaN crystal structure. In addition, leakage current through the solutions was found to be approximately 1nA which is on average 10^5 times less than the current through the nanowire device. We demonstrate via fluorescence microscopy the amine-reactive surface functionalization of GaN nanowires. The preparation scheme utilizes successive wet chemical treatments, allowing on-chip functionalization of pre-fabricated bridge-type nanowire structures. We present strong evidence that piranha etch increases the concentration of reactive hydroxyl groups on the nanowire surface, increasing conjugation of methyl-terminated silane molecules (aminopropyltrimethoxysilane [APTMS]). We have collected I-V data from devices before and after silanization which indicate a 1.5x resistance increase with the deposition of silane. An amine-reactive rhodamine-derivative fluorescent dye is then reacted with the silane molecule, allowing for fluorescence imaging using a confocal scanning laser microscope (CSLM). The degree of functionalization is quantified by the intensity of fluorescence, calculated using selective area image processing and reported as pixel counts above background. We have thus demonstrated an electrically stable, amine-reactive, GaN nanowire-based device structure suitable for bioFET development. The photolithography process allows for integration into massively arrayed IC devices, and on-chip, post-processing functionalization provides flexibility of choice between other functionalization schemes yet to be developed.