Dear all, we’ve recently having trouble preparing a 3 M stock solution of DL-Malic Acid, pH 7 (which we had, so it’s doable!). When we reach pH 3 - 4 the solution turns milky white and does not goes back to a clear solution even when the pH is raised. Does anybody have any advice on how to get a clear solution? Has anyone gone through the same? Thanks in advance, ciao, Sebastiano -- Sebastiano Pasqualato, PhD Crystallography Unit Department of Experimental Oncology European Institute of Oncology IFOM-IEO Campus via Adamello, 16 20139 - Milano Italy tel +39 02 9437 5167 fax +39 02 9437 5990 web http://is.gd/IEOXtalUnit