Australia's Science Forum

We have been using both bromothymol blue and tes-tape for sugar detection in various foods. Our supply of tes-tape has run out and the previous supplier no longer stocks it, only strips that have a small amount of testing paper on the end and these are expensive. The tes-tape is 400cm of continuous testing paper that can be cut into tiny bits for student use. It is made by a US company called "Lilly". It is easy for the kids to use and doesn't require heating as the bromothymol blue does. Does anyone know where I can get some more Tes-tape from?

Hello,

Look into getting glucose strips from chemists. Not TOO expensive, you can even ask for out of date stock which will identify the presence of glucose, but not accurectly the level.

Regards
Michelle

Hi Jen,
the writing was on the wall for us years ago regarding the supply of rolls of test tape for sugar detection. We had to move to Clinistix for glucose detection from Southern Biological, 03 9877 4597. It comes in packs of 50 strips. Code: G10.39; $14.80/100.
Regards,
~Robyn

Jen

You can also use Benedict's Solution it only looking for the presents (not being quantative) of Glucose. It can be bought or you can make it your self very cheaply:

17.3g Copper Sulphate (hydrated)
100g Sodium Carbonate (anhydrous)
173g Sodium Citrate (hydrated)
1L Distilled Water

Disolve the Sodium Carbonate and Citrate in 750mls warm water and filter.
Disolve Copper Sulphate in approx 100mls cold water.
Pour the Citrate-Carbonate solution into a large beaker and add the Copper Sulphate slowly with constant stirring.
Make up to 1L.

to use:

take 1ml Benedict's soluto to 5 ml test solution and heat.

If Glucose is present the solution turns Orange in colour.

For those who have the "The Laboratory" A Sience Reference & Preparation Manual its on Page 113 in my version.

Kim

Oops!!! Sorry Kim, I did mean Benedicts, not bromothymol blue. Brain hasn't kicked into gear yet, still in holiday mode!!
We do use benedicts but I believe you need to heat it to see colour change, unlike the old tes-tape which is quick and easy.
Thanks for the info.
Jen

From what I understand Tes- tape isn't manufactured anymore. We also use Clinistix or Uristix, also available from Sthn Bio.
Uristix have 2 pads - one for protein & the other for glucose which we use when the students are doing food tests.They work well & it saves having to use Biuret.

Jen

Benedict you must heat for it to work correctly.

Kim

PS Biurets is for detecting Protein

Kim