From:"J. A. Kiernan" <>

On Tue, 31 Jul 2001 wrote:
>> Frank Manconi (where?) asks:
>>>I was wondering if there was anyone in the group that has used SLIDE BRITE, 
>>> a xylene substitute, and what they thought of it.<<
> There are two classes of xylene substitutes in common use, limonene and 
> aliphatics. If it's fairly new, it's probably an aliphatic. These are 
> synthetic hydrocarbons similar to the petroleum cut called naphtha. They have 
> different flash points and different distillation characteristics, and are 
> not interchangeable with each other in distillation routines, no matter what 
> the MBA in the corner office says.

Spot on! Slide Brite is odourless, so it's probably an aliphatic 
hydrocarbon solvent such as a mixture of hexanes. octanes etc.
It didn't mix transparently with alcohol and xylene when I tested
it. The label on the bottle gave no indication of what it might
contain. What is the reason to use it?

It's very easy to test miscibility of solvents. Mix and look.
If there's cloudiness that doesn't quickly disappear with
shaking, they are not miscible. If you are approached by a
salesperson of a secret solvent, ask him/her to demonstrate
that the product is miscible with 98% alcohol and with
melted wax and with the mounting medium that you routinely
use. Miscibility with 100% alcohol is not good enough,
especially when blocks or slides are dehydrated by machines.

John A. Kiernan
Department of Anatomy & Cell Biology
The University of Western Ontario
London,  Canada   N6A 5C1

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