You're probably having some difficulties because of the nature of microchannels, which I'm not well versed in. However:
1). That is more alcohol in the phenolphthalein than is needed, 30-50% alcohol in water is adequate to dissolve a tiny amount of phenolphthalein.
2). I don't see why you're using alcohol to dissolve NaOH, your microchanel application may need it, but you should expect solubility problems
3). Outside of the microchannel, I don't mix more than a few drops (approx < 1 ml) of phenolphthalein per 100 mL of solution to be titrated, so you may want to dilute the phenolphthalein even further.
You need less alcohol and phenolphthalein in your system, dependent on your needs, surface tension, and your ability to detect a color change in a very small volume.