[Histonet] Chemicals with no expiration

[Morken, Timothy]

Kathy, I actually posed that question to Fisher Scientific and got a letter back saying that if the chemical is known to be unstable then they will give it an expiration date (shown below). Chemicals that are very stable are considered to have indefinite shelf life. 

Here we label liquids at 3 years and solids at 5 years. Note that anhydrous powdered chemicals are less stable than their hydrated versions so could have a shorter shelf life depending on humidity in your lab. 

In general I try to order chemicals in quantities that will be used up within a year so we maintain a reasonable turnover. That is not possible with some things for which a little goes a long way so we just re-validate those when needed.


Tim Morken
Supervisor, Electron Microscopy/Neuromuscular Special Studies
Department of Pathology
UC San Francisco Medical Center



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The letter from Fisher:

Chemical Services Group
Technical Helpline (800) 227-6701, opt, #1
Cert. of Analysis and MSDS (201) 703-3165
Fax (201) 703-3159

August 16, 2010

Re: Acetic Acid (A35), Ammonium Hydroxide (A665), Hydrochloric Acid Cat (A144)	
		
Dear Tim Morken: 

This is in reply to your request for information pertaining to shelf life.  Some of the chemicals from Fisher may not have an expiration date, simply because those materials should not decompose under normal storage conditions.   They should have an indefinite shelf life if they are not contaminated or adulterated.  If you are buying a product from Fisher Scientific Company and the product has a known instability, an expiration date will be noted on the label.  The stability/shelf life was established by testing sealed and previously opened bottles over the duration of the shelf life period.

Unless otherwise specified, the expiration date will be the last day of the month indicated on the label. 


It is good Chemical Practice, however, not to keep chemicals beyond 3 to 5 years.  Over extended periods of time and/or conditions beyond your direct control, degradation of even stable compounds could occur.  Generally, the first two digits of the six digit lot number of Fisher Chemicals will indicate the year of manufacture.

Storage conditions for all Fisher chemicals should be room temperature unless other wise stated on the label.

I trust that you will find this information useful.  Please call if we can be of further help.

Sincerely,
The Fisher Chemical Services Team


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-----Original Message-----
From: histonet-bounces <@t> lists.utsouthwestern.edu [mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of Kathleen Bess
Sent: Wednesday, February 27, 2013 11:21 AM
To: histonet <@t> lists.utsouthwestern.edu
Subject: [Histonet] Chemicals with no expiration

Hi all,
 
First time using histonet- I read earlier that reagents/chemicals used in the lab with no expiration date are to be labeled with an expiration date of 5 years after having been opened. Is there literature on that? I need to update my policy and prodedure for CAP. Also, this maysaound silly, but do you label your DI water too?
 
Thanks in advance,
 
Kathy Fernandez
Lead Histotech
Saddleback Memorial Medical Center
Laguna Hills, CA
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