The preparation of your solutions should be included in your SOP. The lot numbers of your chemicals cannot be transferred to the solutions you prepare because they are a different thing. You should determine the shelf time of your working solutions and write it in the label, along with the date they were prepared. René J.
--- On Fri, 6/25/10, Brandi Higgins <brandihigg...@gmail.com> wrote: From: Brandi Higgins <brandihigg...@gmail.com> Subject: [Histonet] Prepared Solutions To: histonet@lists.utsouthwestern.edu Date: Friday, June 25, 2010, 12:33 PM Hello All, I work in a small lab where we purchase most of our chemicals already prepared. The only solutions we routinely prepare ourselves are our acid alcohol and acid water for our staining procedures, Carnoy's Fixative (since it needs to be fresh) and our 50%, 70% etc alcohol solutions for our Pap stain and for our processing machine. I would also like to start preparing our 1% and 3% acetic acid solutions instead of purchasing them since I have glacial acetic acid on hand anyway for our Carnoy's Fixative (not that the acetic acid acid solutions are expensive but every dollar counts, plus the shipping charges always shock me). My questions are 1 - in your labs, do you have a policy with instructions on how to prepare each solution? (eg 1 ml acetic acid diluted with water to 100 ml to prepate 1% Acetic Acid Aq and is it neccessary to say 500 ml water and 500 ml reagent alcohol to form 50% alcohol) 2 - when you label the solutions you prepare, do you transfer the lot numbers and expiration dates of the chemicals that were used to make the solutions onto the new chemical bottles and use the expiration date of the concentrated chemical as the expiration date of the prepared chemical? Thanks in advance for all input. Im always amazed at how fast, how many, and how thorough/helpful the responses are! Brandi Higgins, BS, HT(ASCP) _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet _______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet