acid washing glassware assures that all potentially contaminating metallic
ions are removed from the surfaces of the glass. this is particularly
important when performing redox stains like silver stains or iron stains.
acid washing can be as simple as rinsing the soap and water cleaned
glassware with 1 N nitric acid(aq)followed by three rinses of distilled
water or by flooding the soap and water cleaned glassware with chromic acid
(concentrated sulphuric acid saturated with potassium dichromate) followed
thorough running tap water rinse followed by three rinses with distilled
water. The chromic acid method, although the best chemically, is frowned
upon today due to the toxicity of the chromates and the waste disposal
problems arising from its use. For our histology lab purposes; soap and
water>>nitric acid>>distilled water is more than sufficient.  Hope this
helps, Donna Montague, UAMS Orthopaedic Research

-----Original Message-----
From: MacDonald, Jennifer [mailto:jmacdonald@sach.org]
Sent: Wednesday, August 11, 1999 10:38 AM
To: 'histonet@pathology.swmed.edu'
Subject: acid washed glassware


Is anyone out there acid washing their glassware?  If so what type of acid
are you using?  Do you acid wash all glassware or just after certain
staining procedures (ie silver stains)?

On another note:  I would be interested in any feedback on the BioGenex
Optimas Plus (reliability, quality of stains, service problems etc).


Jennifer MacDonald
San Antonio Community Hospital
Upland, CA  (909)985-2811 ext.4148
jmacdonald@sach.org