11/20/97

I have a vial of copper TEM grids that are very hydrophobic. Does anyone

know how I can make them wettable? Acid rinse? Alcohol rinse? Detergent

rinse? Buy new grids?



TIA



Bob



Dr. Robert R. Wise

Department of Biology and Microbiology

University of Wisconsin-Oshkosh

Oshkosh, WI 54901



(920) 424-3404 tel

(920) 424-1101 fax

wise@uwosh.edu

www.uwosh.edu/departments/biology/wise/wise.html

I barbecue my grids just before I pick up sections.

Pass them several times quickly over the flame from an alcohol lamp or

disposable lighter. With a little practice, you'll have clean,

hydrophilic grids with no melted bars! Even with slim bar grids.



Aloha,

Tina



http://www.pbrc.hawaii.edu/bemf/microangela/

****************************************************************************

* Tina (Weatherby) Carvalho * tina@pbrc.hawaii.edu *

* Biological Electron Microscope Facility * (808) 956-6251 *

* University of Hawaii at Manoa * http://www.pbrc.hawaii.edu/bemf*

Holding each grid in tweezers, dip it into the mouth of a bottle

containing concentrated nitric acid, for about 1 second. The fumes will

render the grid hydrophilic without tarnishing the copper.



Ray Egerton, Physics Dept, University of Alberta, Edmonton, Canada T6G 2J1

Phone: 403-492-5095, FAX: 403-492-0714, e-mail: egerton@phys.ualberta.ca

If using uncoated grids, when ready to pick up sections, simply pass the

grid through an alcohol (not gas) flame to cherry color (almost

instantaneously). This may slightly discolor the grid but it is now

extremely hydrophilic. This takes some practice since most people tend to

overheat and damage the grids but it is very convenient.



Individual grids may also be cleaned as needed by dipping (5-10x) into 4%

nitric acid and then dipping several times in distilled water.



Groups of grids may be cleaned by swirling in 4% nitric acid for several

minutes and rinsing in distilled water. Then rinse in ethanol and dry in an

oven.

John J. Bozzola, Ph.D., Director

Center for Electron Microscopy

Neckers Building, Room 146 - B Wing

Southern Illinois University

Carbondale, IL 62901

U.S.A.

Phone: 618-453-3730

Fax: 618-453-2665

Email: bozzola@siu.edu

Web: http://www.siu.edu/departments/shops/cem.html

Dear Bob,

I put the grids in a plasma cleaner for ~1 min; this may be more

difficult than the other methods suggested.

Yours,

Bill Tivol

tivol@wadsworth.org

I was interested to see the various responses to this question, as my own

solution has been to wash the grids in fairly concentrated NaOH for a few

seconds, followed by several distilled water rinses.

Anthony J. Garratt-Reed

MIT Room 13-1027

77 Massachusetts Avenue

Cambridge, MA 02139-4307

United States of America



Ph: 617-253-4622

Fax: 617-258-6478

Bob,

A lot of good suggestions, but I keep a stock of 3% HCl in 95% Et-OH

on hand for this purpose. In bulk, I swirl them in a small amount of the

cleaning solution for ~30 sec., rinse several times with DH2O and dry

them using a Buchner funnel with a piece of filter in the bottom. They

remain hydrophylic for quite a while (days,weeks?) before they need to

be treated again. Individually, they may be dipped 2-3 times in the

cleaning solution, dipped several times in DH2O, dried on filter paper

and used.

Bill Chissoe III

Electron Microscopist,University of Oklahoma

E-mail: wchiss@ou.edu Ph. (405)325-4391

Bob, a real easy way to make them hydrophilic is to use a small flame from

e.g. an ethanol spirit lamp. Whisk each grid through the flame so it

flashes red. Too long and its oxide! Makes them quite hydrophilic.

Melvyn Dickson <M.Dickson@unsw.edu.au

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