Methylenediphosphonic medronic acid

All solvents and reagents used for metabolite extraction and analysis by LC/MS and DESI imaging were of LC/MS grade. Acetonitrile, methanol and water were purchased from Honeywell (Charlotte, NC, USA), and ammonium bicarbonate, methylenediphosphonic (medronic) acid, ammonium hydroxide and formic acid were purchased from Sigma-Aldrich. The sodium carboxymethylcellulose (CMC) used for preparing zebrafish for DESI imaging was purchased from Sigma-Aldrich. Hydroxychloroquine sulfate was pharmaceutical grade and purchased from Sigma-Aldrich, ¹³C₆-glucose was purchased from Cambridge Isotopes (Tewksbury, MA, USA), and penicillin-streptomycin was purchased from Life Technologies (Carlsbad, CA, USA). The labeled HCQ-D₄ internal standard used for absolute quantitation was purchased from Cayman Chemical (Ann Arbor, MI, USA).