Sanjana Skumar

6 Questions 18 Answers 0 Followers

Questions related from Sanjana Skumar

NMR for buffered solutions?

I wanted to study structural /functional group changes of a compound at alkaline buffer (pH 12). But for buffers, salts and NaOH used will have hydrogen in them. So the solvent peak will mask all...

22 January 2020 9,233 5 View

When I run a crude extract in reverse phase (C18) HPLC column, all the compounds are eluted out as a large peak along with the solvent peak. How?

The sample (ethyl acetate plant extract (1mg/ml)) was prepared in methanol and the injection volume is 20ul. I have tried three different mobile phases: gradient 0-100% acetonitrile in water,...

14 November 2017 9,105 12 View

How to purify thin needle shaped crystals?

I have a mixture of compounds from which one is forming crystals. From fractional crystallization, I found that the impurities and the crystals dissolve in the same solvents. Also, the crystals...

17 August 2017 2,856 13 View

In silica gel column, when eluting a compound, I obtain much previous compounds (which were previously eluted out) along with the new compound. How?

I am running ethyl acetate extract on silica gel column using hexane and ethyl acetate as mobile phase ( by stepwise-gradient increase of polarity). When the compound elutes, I run in the same...

28 July 2017 1,107 7 View

I am trying to purify flavonoids using activated charcoal. What is the best method to recover those flavonoids?

The flavonoid of interest is polar in nature. The flavonoids were adsorbed onto acid pre-treated activated charcoal (packed in column) from ethyl acetate solution. I tried recovering with...

13 August 2016 2,069 8 View

How reliable are biochemical tests for quantification of unknown compound?

I want to determine the concentration of a flavonoid molecule. The error due to weighing is quite high as the amount of sample is less. So, I thought of trying biochemical tests like Aluminium...

01 January 1970 2,336 4 View