Rotenone 1964 Volume

The spectrum of pesticides examined contained all different types of pesticides. So, besides the biogenic pesticide rotenone in water after SPE [73] acidic pesticides in water [74, 75] or soil [76] as well as non-acidic compounds were under research. Cappiello et al. identified and quantified [77] 13 acidic and 32 basic-neutral pesticides in water samples. With the application of large-volume injections for the analyses of these compounds [75, 78] an improvement in sensitivity was observed which made trace analysis possible. The variation of the ionisation mode, El,... 

Estimation of Rotenone Content. Dilute the sample with acetone so that the final solution contains about 0 02 per cent of extract. Pipette 1 ml of this solution into a dry 25-ml Erlenmeyer flask and add 1 ml of acetone. Add 2 ml of freshly prepared alkaline sodium nitrite solution, (one volume of 40 per cent w/v potassium hydroxide solution and seven volumes of 0 1 per cent sodium nitrite in 95 per cent ethanol), and place the flask in a water-bath at 20°. After seven minutes, add 5 ml of 25 per cent v/v sulphuric acid solution, stopper, shake sufficiently to mix, and return the flask at once to the water-bath. The bluish-red colour which develops reaches a maximum after fifteen minutes and is then stable for about one hour. 

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