Caledon 88 multi element standard

Diet samples (~0.5 g) were weighed in quartz beakers and dried overnight in an Isotemp oven (Thermo Fisher Scientific) at 100°C. Samples were ashed using a combination of dry ashing using a Thermo Scientific Lindberg/Blue MTM box furnace (Thermo Fisher Scientific) and wet ashing using concentrated trace metal grade nitric acid (Thermo Fisher Scientific). Ashes were solubilized in dilute nitric acid. Solubilized ashes and urine samples were analyzed for mineral concentrations using a radial view 700 Series inductively coupled plasma optical emission spectrometer (Agilent Technologies Canada Inc., Mississauga, ON, Canada). Operating conditions have been described previously [58 (link)]. Standard calibration curves were prepared using the CALEDON-88 multi-element standard (Inorganic Ventures, Christiansburg, VA, USA) and analytical precision was verified using National Institute of Standards and Technology traceable reference material (SCP Science, Baie D’Urfé, QC, Canada).

Diets (~1 g samples) and femurs were placed in preweighted quartz beakers and dried overnight at 100 °C in an Isotemp^® oven (Thermo Fisher Scientific). Samples were cooled, placed in a desiccator for 1 h and then weighed to obtain dry weights. Diets and femurs were ashed using a combination of dry ashing using an Isotemp^® Programmable Forced Draft Furnace (Thermo Fisher Scientific) and wet ashing using concentrated trace metal grade nitric acid (Thermo Fisher Scientific). Ashes were solubilized in dilute nitric acid. Solubilized ashes and urine samples were analyzed for mineral concentrations using a 700 Series inductively coupled plasma optical emission spectrometer (Agilent Technologies Canada Inc., Mississauga, ON, Canada). Operating conditions have been described previously [35 (link)]. Concentrations of minerals were derived from a standard calibration curve prepared using the CALEDON-88 multi-element standard (Inorganic Ventures, Christiansburg, VA, USA). Analytical accuracy was verified using National Institute of Standards and Technology traceable reference material™ (SCP Science, Baie D’Urfé, QC, Canada).