Icap qc

Analysis of Se content in the placenta was performed as described previously [78 (link)]. Each placental sample was precisely weighed on an analytical balance and transferred to a microwave cuvette. Four milliliters of nitric acid (65%) and 1 mL of hydrogen peroxide (30%) were added to each microwave cuvette. Microwave digestion was performed at 180 °C (the temperature was gradually increased to 180 °C for 20 min and remained at the same value for an additional 10 min). Next, the cooled, digested samples were diluted with Milli-Q water into 25 mL normal vessels. Se was quantified using inductively coupled plasma mass spectrometry (ICP-MS, iCAP Qc, Thermo Scientific, UK) in the optimized mode of action and by applying internal standardization. Good linearity (R > 0.999) was obtained in the range from 1 to 300 µg/L. The accuracy of ICP-MS was controlled by SRM (Seronorm™ Trace Elements Whole Blood Level-1, Sero, Billingstad, Norway) and the recorded recovery values were in the range of 96.6 to 105%.

All samples were processed,
prepared, and analyzed in the SWAMP lab. Sample bottles were opened
only when inside class-100 laminar flow clean air cabinets (NuAire
Laboratory Equipment). Samples were analyzed inside a class-1000 clean
room. Dissolved TE concentrations were measured using quadrupole ICP–MS
with high-purity He collision gas (iCAP Qc, Thermo Fisher Scientific).
To ensure accurate results and the absence of matrix effects, standard
reference materials for TEs in surface waters (SRMs; NIST 1640a and
SPS-SW2) were respectively measured at dilution factors of 10-fold
and 100-fold and 100-fold and 500-fold after every 12–15 samples
(recoveries deemed acceptable when between 80 and 120%). Detection
limits were determined as the mean concentration + three times the
standard deviation corresponding to the number of counts per second
in five blanks of 2% HNO₃. Instrument running and quality
control parameters are provided in the Supporting Information and in previous publications^{7 (link),30 (link)} (Tables S3–S6). Samples for quasi-total
TE concentrations (i.e., acid-extractable) were first solubilized
in pure double-distilled nitric acid using high-pressure and high-temperature
microwave-assisted digestion (UltraCLAVE, ATS Scientific). Soil and
water SRMs were also digested and analyzed to ensure adequate recovery
(NIST 1640a, 2711; SPS-SW2).

Highly sensitive analysis of the bone-implant-interface was performed using a laser ablation system (LSX 213, CETAC Technologies, Omaha, NE) coupled to an inductively coupled plasma quadrupole mass spectrometer (iCAP Qc, Thermo Fisher Scientific, Bremen, Germany) as described by Blaske et al. [19 (link)] to address possible migration of metal components from the stem surface into the surrounding tissue. A collision/reaction cell was used for quadrupole-based MS detection to discriminate polyatomic ions (⁹¹Zr¹⁶O⁺), resulting from the blasting process of the titanium stem, which could possibly interfere with ¹⁰⁷Ag⁺, by their kinetic energy.

Whole flour (0.2 g) samples were introduced into digestion tubes for digestion with 6 mL of nitric acid (HNO₃) in a microwave digester. The digested solutions were filtered through a 0.45 μm water-based microporous membranes after dilution to a constant volume of 50 mL with deionised water. Subsequently, the concentrations of different metal elements including, Ca, Mn, Fe, Cu, Zn, Se, As, Cd, and Pb, were determined using inductively coupled plasma-atomic emission spectrometry (ICP-MS, Thermo Fisher, iCAP Qc). The standard curves for the different metal elements are shown in Fig. S1, and the correlation linear valuer [2 (link)]. was between 0.9977 and 0.9999. The recovery rates of all the elements ranged between 80 and 120%.

To obtain the surface morphologies and the content of zinc, the composites were investigated by using transmission electron microscopy (TEM, Hitachi, H-7650, Tokyo, Japan) and scanning electron microscopy (SEM, Hitachi, S-4800) combined with an energy dispersive X- analysis system. The chemical compositions of the bamboo were tested by the Fourier transform infrared spectroscopy (FTIR, Nicolet 6700, Waltham, MA, USA). A X-ray diffraction (XRD) instrument (Bruker, D8 Advance, Karlsruhe, Germany) was used to carry out the XRD measurements by utilizing Cu Kα1 radiation in the 2θ range of 5°–60°. The thermal performances of the samples were investigated by a TG analyzer (Q600, TA Instruments, New Castle, DE, USA) from 25 °C to 1000 °C under a nitrogen atmosphere with a heating rate of 10 °C·min⁻¹. The release of zinc ions was tested by inductively-coupled plasma mass spectrometry (ICP-Ms, Thermo, ICAP-QC, Waltham, MA, USA).