Microarrays are a completely different beast as they just refer to dense printing on a surface. They do not need to be antibody based (as opposed to ELISA). In fact, it is more commonly refering to nucleic acid-based arrays. Analytical they offer different advantages due to the technical aspects of an array. For example, the dynamic range tends to be less than in ELISA and the quantification requires is not trivial as variance in the printing process or even the way they are printed will alter the process. As such it is more often used in explaratory rather than in quantiative studies, though with proper normalization they can also be used as such. I.e. there are a lot of techical differences that affect outcome making them very differnt tools.
The overall issue is that upscaling and method transfer are not trivial things. even if the methodology appears to be roughly similar. As an analogy, one could argue that all chromatography is basically the same (using a stationary and a mobile phase) but obviously the actual execution matters a lot.
Edited by CharonY, 4 January 2017 - 09:28 AM.