Since RNA quality is critical in obtaining good microarray data, it¡¯s required that all starting RNA must pass the quality check. Currently we have a Agilent 2100 bioanlayzer instrument using its NanoChips to check the RNA quality, running the 2100 Expert software.
Based on our experience, a RIN number greater than 8.0 should be good enough for microarray experiment.
The starting tissue or cells should be freshly harvested and immediately frozen in liquid nitrogen. Never let it thaw before you send us (on dry ice or liquid nitrogen). Freshly dissected tissues may also be kept in Ambion RNAlater solution at RT or 4C.
Sample requirements:
2ul total RNA in RNase-free water with concentration greater than 50ng/ul
If your sample"\s" concentration is less than 50ng/ul, you can either concentrate the sample (vacuum dry) or use other alternative of checking the quality, i.e. using PicoChips.