Felicity and others,

> Does anybody know of a fluorescent dye for demonstrating features of a
> cotton fibre?  I am looking at running a prac subject for biologists whereby
> I get them to stain textile fibres (since these are readily available) with
> fluorescent dye and look to see which structures take up the dye.  Can
> anyone tell me what is a good stain to use for cotton?  Are there any
> pitfalls I should perhaps know about in advance?  I made up a fluorescein
> dye both in water and in ethanol but had minimal luck with these.  The
> literature is quite sparse but I believe the wall of the cotton fibre to be
> made of cellulose.

The most well known stain for cellulose used to be Calcofluor white,
now called Fluorescent Brightener (Sigma # F6259). However, it is a
UV dye, but may excite also in the blue region. Haven't used it
myself, so can't comment further.

Ian.


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Dr Ian Harper
Experimental Biology Programme
Medical Research Council
PO Box 19070              Tel: 027-21-938 0347
Tygerberg 7505            Fax: 027-21-938 0456
South Africa
Internet: [log in to unmask]
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Microscopy Society of Southern Africa
           Web Page at
http://www.uct.ac.za/depts/emu/mssa

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