During my reaction of extracting flavonoids I use hexane in a aqueous methanol crude extract to fractionate hexane and aqueous layer but surprisingly I don't get any layers. The hexane is completely dissolved in the aqueous layer ... is this possible?
after that i took some haxane and water in equal amount only, then check its layer no any layer is present ...is it is not haxane or its too old chemical.?
Hi,
try changing the solvent from hexane to ethyl acetate, better separates substances and is often used in flavanols.
OK..THANX .im using haxane to remove fatty substance then i use ethyl acetate and n-butanol.
I understand you are using aqueous methanol so methanol is soluble in haxane so you are getting soluble part
Dear Riaz Hexane is insolble in water sometiimes we donot recognize the clear separation of layers due to dark colour. You take aqueous methanol suppose 200 ml and extract it with 50 ml of Hexane. Then after standing some time take out methanolic layer 100 ml approx. Again add 100 ml aq methanol. Then solution will be diluted or other wise you can see the layer in the light when it comes near stop cock Or take diluted solution for extraction. Instead of aqueous methanol you can also take plant material in water suppose 160 ml and add 40 ml methanol for solubility.
that is possible if you have surface active agents in your extract which incorporate hexane in water as oil/water emulsion or you did mixing in the wrong way as vigorous shaking cause emulsion try to increase the hexane and shake gently in separator funnel how ever we extract flavonoid by aqueous ethanol not by water
Hexane is diossolved in aqueous methanol and you will not find aqueous layer. Use dry methanol and no hexane. dissolve your crude extract. now add hexane you will get a separate hexane or aqueous layer.
There is some thing wrong with your chemicals either I just now did with methanol and hexane.
Yup brijesh my hexane is too old....i change it and fortunately i got my result...
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