I prepare my own Lugol,s iodine solution ( concentrate):

ACID ONE: 100g KI 50g I2 1in 1l distilled water + 100g glacial acetic for samples with pH=7 (Utermöhl 1958)

i add 0,5-1 ml Lugol /100ml sample

best regards

And preserve in Amber Glass, store protected from light

best regards

Tincture of iodine can be and used to be used in preserving phytoplankton specimens similar to Lugol's iodine solution but I believe the presence of 1:1 alcohol is not always desirable as preservative when you need to view certain intracellular features under the microscope to identify the species and the alcohol as coagulant of protein structures does not always help. Moreover, the same property of alcohol may hinder the permeability of the tri-iodide ions in the cells by modifying the water channel ultra structures and the purpose of using iodine as a preservative may get nullified by that. You can always prepare your own Lugol's iodine solution on the basis of your need as mentioned by Maria.

Best regards,

Dr. Abhishek Mukherjee

@Abhiskek

I was hoping to buy these in store. Tincture of iodine is much more easier to obtain so I was wondering if I could use that instead. My goal is to get phytoplankton concentrations, that's it.

@Adam

In your case you can use either or both of them on separate phytoplankton concentrates. It will be good for you to get a comparative measure on which one you thought better.

Yes, I used but only in emergency case (the Lugol's bottle was broken in the filed, so we went to the nearest chemist shop and bought iodine tincture). I did not experience any problem, but we were keen to count those samples as soon as possible.

It can be used if we preserve for shorter time. It can used drop by drop till brownish color appears. you can also use 4% formaldehyde sol. for preserving water samples.

I had used it. As for me, there's no difference with lugol formulations. And, like with lugol, you should add formaline for prolonged storage, because iodine evaporates with time.

As far as I remember, @Maria Verdugo Althöfer and me used iodine tincture in some samples from Guadiana river. It was used because we have not enough Lugol or something similar. Moreover, we use a higher concentration (just in case) because the iodine tincture was not pure (maybe 5%, but I do not remember it). After that Maria told me that we had no problems with the samples and they were perfectly preserved, but, it is also true that we did feel conformtable/sure about that and you analysed them as soon as possible. To sum up, it works, at least in case of emergency. Trust on @Maria Verdugo Althöfer!!

Jorge, exactly what I did once. See above.

Can I use Lugol's iodine solution to preserve my algae samples for the estimation of live and dead algae cells through Promega Glomax Explorer?