Sample Requirements

For the full service cDNA microarray analysis, at least 15ug of high quality total RNA is preferred at an optimal concentration between 0.5ug/ul to 1.0ug/ul while the Affymetrix protocol typically requires 2-5ug (contact facility regarding low sample amounts).  Upon request, we can return any unused sample amount to the researcher.  We have found that the greatest overall factor affecting microarray data quality is the quality of the starting total RNA.  High purity RNA is essential for obtaining good results. Therefore, spending extra time on sample cleanup is critical. For best results, our facility recommends extracting RNA from cells using the RNeasy Mini Kit from Qiagen. If using mammalian tissue as the source, we recommend isolating total RNA using TRIzol, followed by cleanup using RNeasy Mini Kit. Although the DNAse treatment step in this protocol is optional, we have found this step to be important if genomic DNA contamination is a factor. Finally, the RNA should be quality controlled through RNA quantitation and gel electrophoresis. Please submit these results along with your sample. We will also perform an RNA quality check using our new Agilent 2100 Bioanalyzer. Experimental samples are usually submitted along with a control sample for comparison.