Flashsmart chns elemental analyzer

All common laboratory chemicals were purchased from commercial sources and used without further purification: 8-hydroxy-2-quinolinecarboxaldehyde, ≥96% (Sigma-Aldrich, St. Louis, MO, USA); thiosemicarbazide, ≥99.9% (Fluka, Buchs, Switzerland); 4-methyl-3-thiosemicarbazide, 97% (Fluorochem, Hadfield, UK); 4,4-dimethyl-3-thiosemicarbazide, ≥98.0% (TCI, Tokyo, Japan); 4-phenyl-3-thiosemicarbazide, 99% (Sigma-Aldrich); gallium nitrate hydrate, 99.9% (Sigma-Aldrich); indium nitrate hydrate, 99.9% (Sigma-Aldrich). NMR was recorded on a Bruker Anova spectrometer at 400 MHz (Billerica, MA, USA), with chemical shift reported in δ units (ppm). NMR spectra were referenced relative to residual NMR solvent peaks. The solvent used in the spectra’s acquisitions is DMSO-d₆. The FT-IR measurements were recorded on Nicolet 5PC FT-IR (Rodano, MI, Italy) in the 4000–400 cm⁻¹ range, equipped with the ATR accessory. Elemental analyses were performed using the Thermofisher Scientific Flashsmart CHNS Elemental Analyzer (Rodano, MI, Italy). ESI-MS were recorded on a Waters Acquity Ultraperformance ESI-MS spectrometer with a Single Quadrupole Detector (Sesto San Giovanni, MI, Italy). UV/Vis spectra were collected using a Thermofisher Scientific Evolution 260 Bio Spectrophotometer (Rodano, MI, Italy), using quartz cuvettes of 1 cm path length.

Green algae C. reinhardtii (CC1690) were grown in 1‐L vessels with BG11 medium (Stanier et al., 1971 (link)). P‐limited algae were obtained by reducing K₂HPO₄ by 10‐fold from 40 to 4 mg/L, while N‐limited algae were obtained by reducing the concentration of NaNO₃ by 30‐fold from 1.5 to 0.05 g/L. No modification of medium was made for the normal group. Algae were cultured in a chamber under constant temperature of 23.5℃ and a 14:10 light/dark cycle (20 μmol/m² s⁻¹). Concentration of algae was measured daily by a Beckman Coulter Z2 Cell and Particle Counter (Beckman Coulter Inc.). Cellular carbon (C) and nitrogen (N) of algae in three conditions (i.e., normal, N‐limited, and P‐limited) were quantified by a FlashSmart CHNS Elemental Analyzer (Thermo Fisher). Cellular P was analyzed as orthophosphate after acidic oxidative hydrolysis with 1% HCl. The concentration of PO₄³⁻ was measured manually according to a previous report (Strickland, 1968 ).