Icp standard certipur

Sample mineralization was conducted according to Mihăiescu et al. [34 ]. Briefly, 0.5 g of sample was homogenized with HNO₃ 65% and 3 mL H₂O₂, and mineralized in a Berghof MWS-2 (Berghof, Achalm, Germany), following the program parameters described by Mihăiescu et al. [34 ]. After, the samples were made up with ultrapure water to 25 mL volumetric flask. Furthermore, according to Senila et al. [35 (link)] the inductively coupled plasma optical emission spectrometry (ICP-OES) tool was used for sample analysis.
For analysis, s spectrometer Optima 5300DV (PerkinElmer, Waltham, MA, USA), with a dual viewing inductively coupled plasma optical emission coupled with CETAC 6000AT+ (CETAC, Omaha, NE, USA) ultrasonic nebulizer. The following parameters were used: 1300 W RF power, 15 L/min plasma flow, 2.0 L/min auxiliary flow, 0.8 L/min nebulizer flow, and the sample uptake rate was 1.5 mL/min. The delay time for washing between each sample and signal measurement was 180 s and high-purity argon was used to sustain plasma as a carrier gas. For calibration, multi-elemental solutions of 1000 mg/L ICP Standard Certipur^® (Merck, Darmstadt, Germany) were used.

Phenotypic analysis was conducted for the whole set of wheat varieties in each season. For each sample, 50 kernels were counted using a digital seed analyzer/counter Marvin (GTA Sensorik GmbH, Neubrandenburg, Germany) and the thousand-grain weight (TGW) was estimated. The samples were milled using a Retsch mill (MM300, Germany) and the milled samples were dried overnight at 40°C. Calcium concentrations were measured by inductively coupled plasma optical emission spectrometry (ICP-OES, iCAP 6000, Thermo Fisher Scientific, Germany) combined with a CETAC ASXPRESS^TM PLUS rapid sample introduction system and a CETAC autosampler (CETAC Technologies, Omaha, United States). Fifty micrograms of dried and ground samples from each variety were wet digested in 2 ml nitric acid (HNO₃, 69%, Bernd Kraft GmbH, Germany) using a high-performance microwave reactor (UltraClave IV, MLS, Germany). Digested samples were filled up to 15 ml final volume with de-ionized distilled water (Milli-Q^® Reference System, Merck, Germany). Element standards were prepared from Bernd Kraft multi-element standard solution (Germany). Calcium as an external standard and Y (ICP Standard Certipur^®, Merck, Germany) were used as internal standards for matrix correction.

Fifty milligrams of dried and milled wheat grain flour was taken to be digested by (2 ml) nitric acid (HNO₃ 69%, Bernd Kraft GmbH, Germany). The digestion process was performed using a high-performance microwave reactor (UltraClave IV, MLS, Germany). All digested samples were filled up to 15 ml final volume with de-ionized distilled (Milli-Q^®) water (Milli-Q Reference System, Merck, Germany). Element standards were prepared from Bernd Kraft multi-element standard solution (Germany). Zinc as an external standard and yttrium (Y) (ICP Standard Certipur^® Merck Germany) were used as internal standards for matrix correction. Zinc concentrations were measured by inductively coupled plasma optical emission spectrometry (ICP-OES, iCAP 6000, Thermo Fisher Scientific, Germany) combined with a CETAC ASXPRESS^TM PLUS rapid sample introduction system and a CETAC autosampler (CETAC Technologies, Omaha, NE, United States).