In article <199402220409.UAA01431 at net.bio.net> GOVINDJEE at C.SCS.UIUC.EDU ("GOVINDJEE") writes:
>From: GOVINDJEE at C.SCS.UIUC.EDU ("GOVINDJEE")
>Subject: Help needed/urgent
>Date: 22 Feb 1994 04:09:17 -0000
>I would appreciate it very much if someone can provide me with a
>reference of a simple method in which photosynthesis of a Elodea branch
>is measured by the oxygen bubbles released upon illumination.I need
>except that the name Winkler method has stuck in my mind. I also
You would be much better off with a dissolved oxygen electrode. Almost any
environmental lab would have one such as a YSI probe. I used one in a 300 ml
BOD bottle or an erlynmeyer flask (classroom expt. in 1973) to measure
respiration of a crab. You could watch changes 'real-time' with variations in
The Winkler method (US EPA Methods for Chem. Analysis of Water and Wastes, (my
copy is 1973)) in a nutshell takes some skill ), 300 ml BOD bottles, sodium
azide MnOH, KI, sulphuric acid and a titration. Basicly, the Mn(OH)2 reacts
with O2 to MnO(OH)2 ppt, dissolve with acid, react with KI to I2, titrate. I
would skip the titration and use a DPD chlorine test kit for drinking water.
>glassware used ? the Winkler apparatus? Where is it available?
Any lab supply house.
>We can either purchase it or build it with full details. This is needed
>Professor of Plant Biology
>Thanks for your help.
DISCLAIMER: I'm not in this business anymore.