Icap 6000 series icp oes

Scavengers S₁–S₇, deuterated solvents, and pyridine were all purchased from Sigma-Aldrich and used as received. 1 was synthesized according to the procedure of Sola et al. [64 (link)] ICP-OES analysis was performed using a Thermo Scientific iCAP 6000 series ICP-OES utilizing Qtegra software(Thermo Fisher Scientific, Waltham, MA, USA) and an iridium wavelength of 224.268 nm.

For extraction of P_labile about 100 mg of dried, milled soil was used. The samples were suspended in 10 ml Bray-1 solution (1 M NH₄F, 0.5 M HCl) and shaken for 5 min at 180 rpm. The samples were afterwards filtered using phosphate free filter paper (MN 280¼, Macherey-Nagel, Düren, Germany). The filtrate was analyzed colorimetrically at 645 nm wavelength (Specord 205, Analytik Jena, Germany) using malachite green oxalate (Sigma, St. Louis, MO, United States) as reagent according to the procedure described by Lanzetta et al. (1979) (link).
Total P (P_tot) was extracted from about 50 mg of dried, milled soil and plant material in 2 ml 65% HNO₃ at 160°C for 12 h according to Heinrichs et al. (1986) . Extracted samples were filtered using phosphate free filter paper (MN 280¼, Macherey-Nagel, Düren, Germany), and used for elemental analysis by inductively coupled plasma–optical emission spectroscopy (ICP–OES) (iCAP 6000 Series ICP–OES, Thermo Fisher Scientific, Dreieich, Germany). Bark and xylem exudates were directly used after filtration for P determinations.