An appropriate amount of the cell suspension was then aspirated using a pipette and transferred into the counting chamber of a hemocytometer, after which erythrocytes were counted under an optical microscope
l-glutamine (Fisher Scientific, 25030081), l-methionine (Sigma-Aldrich, M5308), l-cystine (Sigma-Aldrich, C7602), GSH (Sigma-Aldrich, G4251) or cysteinylglycine (Bachem, 4002969) was added to each condition at the indicated concentrations
Nature 527 , 186191 (2015)
The primary differences are the format (vials versus pre-filled pens), the cost (significantly less expensive), and the fact that compounded medications aren't individually FDA-approved products (though they're legally prepared by licensed pharmacies when the brand-name versions are on the FDA shortage list)
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