RNA Kit v.s. Trizol Method

[c1bl]

I'm wondering if anyone could tell me what the difference is I am seeing between my total RNA samples. The difference is seen between the Sample I extracted using a kit (Lanes 2, 4 and 5) and the samples I extract using the Trizol method (Lane 3 and 6). The kit sample shows a large band in every case (Lane 2, 4 and 5) which is not seen in the Trizol method (Lane 3 and 6). Is this DNA contamination? Also the Trizol method shows more faint bands towards the end of the gel. The kit uses glass fiber matrix columns to filter out the RNA. It says it effectively isolates RNA >200bps. Would the Trizol mehtod be more sensitive at getting lower MolecularWeight RNA than the kit (Lane 3 and 6)?
1% agarose gel of total RNA extracted from young aquatic plant leaf tissue. Lanes 2,4,5 used RNA extraction kit. Lanes 3,6 used the Trizol method. Lanes 1 and 7 are 1kb DNA ladder. Gel was visulized by staining with Ethidium Bromide.

[admin]

Gel reposted here:

[katherine_ft]

It seems that the RNA extract by the kits is more concentratied then that by Trizol method. If what your tried to extract is total RNA, I think the band(lane 2, 4, 5) in the front may be the ribosomal 5s rRNA.

[MARGARITA MARTINEZ]

i am agree whit katherine the kit of extract for ARN is more concentratied
then by trizol.
i have similar kit of glass fiber matrix column and too have other metodo whit
tiozinato of guanidinio for extract ARN and see similar situation.

thank you for share you experiencie.

Margarita

[aquaplasmid]

I can say for >99% sure that lane 2,4,5 had gDNA contamination but lost all tRNA. The band that is closest to well is gDNA.

[xenik]

i'm agree with aquaplasmid - it's genomic DNA near the well. If you want to get rid of it - you must try some DNase I digestion on column method (is there any notion in manual for the kit? some companies provide it as an additional kit). As for small RNAs (especially miRNAs) use Trisol.