The RnaBio RNA Isolation Reagent (RIR) is a quick, economical, and ready-to-use reagent for the isolation of total RNA using the classical acid guanidinium thiocyanate-phenol-chloroform (AGPC) method of RNA extraction. The classical AGPC method is one of the most widely used RNA isolation methods for the last two decades. The RnaBio RIR is an improved version of TRIzol that can be used for the lysis of cells and liquid samples. The addition of chloroform followed by centrifugation leads to the phase separation where the aqueous layer on the top contains the RNA. The precipitation of the aqueous layer with isopropanol followed by ethanol wash leads to the isolation of high-quality total RNA. This can also be used in place of TRIzol to isolate DNA, RNA, and proteins simultaneously from samples, including animal cells, tissues, plants, yeast, and other samples.