Uv 3150 uv vis spectrophotometer

TG-DTA curves were measured with a Shimadzu DTG-60H analyzer to determine the water content of acridinium derivatives and SSA. Absorption spectra were obtained on a UV-3150 UV-vis spectrophotometer (SHIMADZU). Molecular models of acridinium derivatives were depicted by a molecular drawing software (i.e., Chem 3D). The structures of the molecular models were optimized by the semiempirical molecular orbital method using MOPAC 2016. Calculations were carried out by using the following command: PM6 CHARGE = 1 GRAPHF AUX BONDS DENSITY PI ENPART MMOK. The height of acridinium derivatives from their aromatic plane was calculated by the optimized structure. The projected cross-section of acridinium derivatives horizontal to the aromatic plane was defined as the molecular cross-section and was calculated by using an image processing software (Image J). Charge density at nitrogen atoms and energy levels of HOMO and LUMO in acridinium derivatives were calculated by DFT calculations performed at the B3LYP/6-31G* level using Gaussian09 package.³⁵

Thermogravimetry–differential thermal
analysis curves were measured with a Shimadzu DTG-60H analyzer to
determine the water content of Acr and synthetic saponites. The temperature
was ramped from room temperature to 120 °C with a heating rate
of 10 °C/min under dry air as a purge gas and was held for 60
min. Absorption spectra were obtained on a UV-3150 UV–vis spectrophotometer
(SHIMADZU). Fluorescence spectra were obtained on an FP-6500 spectrofluorometer
(Jasco), and the excitation light was set at the absorption maximum
wavelength of each sample. The reproducibility and signal-to-noise
ratio of the fluorescence intensity are 0.5% and 100:1 or higher,
respectively. The fluorescence quantum yield was determined by the
relative method. Rhodamine 6G was used as a standard for the calculation
of the fluorescence quantum yield of Acr with and without synthetic
saponites. The fluorescence quantum yield of Rhodamine 6G in water
is 0.90.^{43 (link)} Fluorescence lifetime was measured
by a C4780 picosecond fluorescence lifetime measurement system (Hamamatsu
Photonics). A Nd³⁺ YAG laser (EKSPLA PL2210JE + PG-432,
fwhm 25 ps, 1 kHz) was used for excitation. The excitation wavelength
was 355 nm. The fluorescence lifetimes were calculated by deconvoluting
the excitation pulse in each measurement range.

TEM images were primarily obtained with a Philips EM300 electron microscope operated at an accelerating voltage of 300 kV. Elemental analysis was acquired with an energy-dispersive X-ray (EDX) equipped with the TEM. Scanning TEM (STEM) image was captured with an FEI Titan TEM with Schottky emitter operated at 200 kV. X-ray diffraction (XRD) patterns were collected by using a Bruker GADDS D8 Discover diffractometer with Cu Kα radiation (λ = 1.5418 Å). Fluorescence spectra were acquired with a SpectraPro 2150i fluorescence spectrometer equipped with a commercial 980 nm NIR laser. Room-temperature UV-visible absorption spectra were recorded with a Shimadzu UV-3150 UV/Vis spectrophotometer. Nano-zeta sizer measurements were performed on a Malvern zetasizer nano series.