Icp oes plasmaquant pq 9000 elite spectrometer

The UV-Vis absorption spectra of the In₂O₃-NPs samples were measured using a double-beam spectrophotometer (Cary 5000 UV-Vis-NIR, Agilent Technologies, Santa Clara, CA, USA). The FTIR spectra for both adsorbents before and after terbium adsorption were collected using a FTIR spectrometer (Vertex 70, Bruker, Germany); the spectra were recorded in a spectral range of 4000–400 cm⁻¹ with a spectral resolution of 3 cm⁻¹. The X-ray diffraction (XRD) data were obtained using a Malvern Panalytical Empyrean 3 diffractometer to determine the phase composition and crystal structure of precursors and In₂O₃-NPs. The morphology and particle size of the samples were characterized using field-emission scanning electron microscopy (FESEM, Quattro S, Thermo Scientific, Waltham, MA, USA). An ICP-OES PlasmaQuant PQ 9000 Elite spectrometer (Analytik Jena, Jena, Germany) was used to determine the initial and final concentrations of terbium in experimental solutions. Zeta potential results were determined on a Malvern zeta potential and particle size analyzer (Zeta sizer Ver. 7.12). They are presented as the mean of many repeated and automated scans (12 cycles). The raw data of measurements are given in Supplementary File S1.

The UV-Vis absorption spectra of the In₂O₃-NPs samples were measured using a double-beam spectrophotometer (Cary 5000 UV-Vis-NIR, Agilent Technologies, Santa Clara, CA, USA). The FTIR spectra for both adsorbents before and after terbium adsorption were collected using a FTIR spectrometer (Vertex 70, Bruker, Germany); the spectra were recorded in a spectral range of 4000–400 cm⁻¹ with a spectral resolution of 3 cm⁻¹. The X-ray diffraction (XRD) data were obtained using a Malvern Panalytical Empyrean 3 diffractometer to determine the phase composition and crystal structure of precursors and In₂O₃-NPs. The morphology and particle size of the samples were characterized using field-emission scanning electron microscopy (FESEM, Quattro S, Thermo Scientific, Waltham, MA, USA). An ICP-OES PlasmaQuant PQ 9000 Elite spectrometer (Analytik Jena, Jena, Germany) was used to determine the initial and final concentrations of terbium in experimental solutions. Zeta potential results were determined on a Malvern zeta potential and particle size analyzer (Zeta sizer Ver. 7.12). They are presented as the mean of many repeated and automated scans (12 cycles). The raw data of measurements are given in Supplementary File S1.

For the measurement of metal uptake, the biomass was separated from the medium by filtering it through a membrane with a pore diameter of 0.22 µm manufactured by Vladipor (Vladimir, Russia) on a vacuum unit, and aliquots of the filtrate were used to analyze the residual content of metals. The concentrations of metals in the control and experimental solutions were determined by an ICP-OES PlasmaQuant PQ 9000 Elite spectrometer (Analytik Jena, Jena, Germany). The calibration solutions and standards were prepared from IV-STOCK-27 (Inorganic Ventures, Christiansburg, VA, USA) standard solution. All control standards were analyzed after every 10 samples.
The content of metal accumulated by biomass was calculated using the following equation: $$\mathrm{q}=\frac{\mathrm{V}({\mathrm{C}}_{\mathrm{i}}-{\mathrm{C}}_{\mathrm{f}})}{\mathrm{m}}$$
where V is the volume of the solution, in mL; Ci and Cf are the initial and final metal concentrations, in mg/L; and m is the amount of biomass, in g.