This is a general reaction for pentose and depends on the formation of furfural.
When pentose is heated with concentration HCl, orcinol reacts in presence of
furfural in presence of ferric chloride as a catalyst purine to produce green color
only the purine nucleotide.
- RNA commercial sample: 10 mg
- RNA solution (0.2 mg/mL): Dissolve 10 mg of commercially available RNA
in 50 mL of buffer saline and use the sample for standard preparation.
- Orcinol reagent: Dissolve 10 gm of ferric chloride (FeCl3)6 H2O in 1 liter
of 1 gm of ferric chloride (FeCl)6 H2O in 1 liter of concentrated HCl and
add 35 mL of 6% w/v orcinol in alcohol.
- Buffered saline.
- Boiling water bath.
Pipette out standard RNA solution in arrange of 0–2 mL into a series of test
tube and make up the volume of each tube 2 mL with distilled water. Add 3
mL of orcinol reagent to each tube for standard solution.
For test solution : Take 2 mL of nucleic acid sodium (isolated from tissue
source.) Add 3 mL of orcinol reagent to each tube, and heat the tube on boiling
water bath for 20 minutes. Cool and take the optical density at 665 nm against
the orcinol blank.
Result: Concentration of RNA present in the given sample is ..............