Uv 1601 uv visible spectrophotometer

The total polyphenol content (TPC) of rocket leaves was determined by the Folin-Ciocalteu method reported by Toledo-Martín et al. [36 (link)], with modifications. Briefly, 400 mg of lyophilized rocket leaves was added to 8 mL of ethanol (with 1% hydrochloric acid) and shaken for 30 s and centrifuged at 4000× g for 15 min. To 180 μL of the supernatant, 300 μL of Folin-Ciocalteu reagent, 4800 μL of deionized H₂O, and 900 μL of a 20% Na₂CO₃ solution in water (w/v) were added. After incubation for 60 min in the dark at room temperature, the absorbance was read at 765 nm using a UV-1601 UV-Visible spectrophotometer (Shimadzu, Milan, Italy). A calibration curve (R² = 0.99) was constructed with gallic acid at different concentrations (25, 50, 100, 150, 200 mg/L). The results were expressed as mg of gallic acid equivalent (GAE)/100 g of dry weight (mg GAE/100 g D.W.).

Thioglycolic acid stabilised cadmium telluride (CdTe) QDs were synthesised via the aqueous synthesis route, and characterised, by the Prof. Gun'ko Research Group (School of Chemistry, Trinity College Dublin, Ireland) using published procedures (Gaponik et al., 2002; Maguire et al., 2014). Aluminium telluride was purchased from Cerac Inc. (Wisconsin, USA), and all other chemicals for synthesis were purchased from Sigma‐Aldrich (Dublin, Ireland).
In this study, 3.2 and 3.6 nm QDs were utilised, and their physiochemical properties are detailed below in Table 1. A Shimadzu UV‐1601 UV‐Visible Spectrophotometer was used to measure QD absorption, with scans carried out in the 300–700 nm range. A Varian‐Cary Eclipse Fluorescence Spectrophotometer was used to determine the fluorescence emission/photoluminescence spectra of QDs. The excitation wavelength was 480 nm, and the emission was detected in the range 490–700 nm, with the quantum yields being calculated from the photoluminescence spectra using Rhodamine 6G as a reference. Zeta potential measurements were carried out using a Malvern Zetasizer Nano Series V5.10. Five measurements were usually taken for each sample, each made of 10 to 20 accumulations as optimised by the machine. QD sizes were determined using their UV absorbance spectra using previously published methodology (Yu et al., 2003).