I have an issue. I isolated RNA from cortex a few days ago. For isolation of RNA i used this procedure:
I homogenizised my sample (mouse cortex) with Trizol. Then to the sample add chloroform, shooke and centrifugate it. After this part i took away the aquatic phase with RNA from mixture and add it to the eppendorf tube with beforehead prepared isopropyl alcohol with glykogen. Again i shook and centrifugate it. In this part i removed isopropyl and let only RNA pelet. Afterwards i did same thing with 75% ethanole. Last but not least i dissolved the pellet with DEPC, checked its concentration on nanodrop.
From nanodrop i saw that one of the sample had been contaminate with guanidine isothiocyanete. So i just desided to repeat steps od my isolation from isopropyl alcohol. To increase precipitation of RNA and increase chance od decontamination i decided to let RNA in isopropyl alcohol precipitate in -80 °C freezer for a night. Unfortunately i fail to remember it untill now.
My question is: Will it affect any integrity of my RNA sample?