Fls980 fluorescence spectrophotometer

The photophysical properties of pristine Rec1-resilin and Pt-NMQCs-Rec1-resilin nanobioconjugates were examined by UV-Vis and fluorescence spectroscopy. UV-Vis absorption spectra of the samples were recorded using an Evolution 201 UV-Vis spectrophotometer (Thermo Scientific Australia Pty Ltd., Melbourne, Australia), whereas steady state fluorescence excitation and emission measurements were recorded using a Cary Eclipse fluorescence spectrophotometer (Varian Inc., Palo Alto, CA, USA). The quantum yield and lifetime measurements of green fluorescent Pt-NMQCs-Rec1-resilin nanobioconjugates were recorded using an FLS980 fluorescence spectrophotometer (Edinburgh Instruments Ltd., Livingston, UK). The concentration of Pt in blue fluorescent Pt-NMQCs-Rec1-resilin nanobioconjugate dispersion was measured using an Optima 5300DV inductively coupled plasma optical emission spectrometer, ICP-OES (PerkinElmer, Melbourne, Australia). The chemical states of the synthesized Pt-NMQCs were examined by X-ray photoelectron spectroscopy (XPS). XPS spectra of Pt-NMQCs-Rec1-resilin nanobioconjugates were recorded using an AXIS Ultra delay-line detector X-ray photoelectron spectrometer (Kratos Analytical Ltd., Manchester, UK), and the binding energies of all peaks were referenced to a C1s value of 284.6 eV.

The morphologies of the hydrophobic nanoparticles, Fe₃O₄-DP-PEG, and Fe₃O₄-Cy, were characterized using transmission electron microscopy (TEM, Talos F200S G2) with an acceleration voltage of 200 kV. The hydrodynamic size and zeta potential of the nanoparticles were measured using a Malvern Zetasizer Nano ZS90. The ultraviolet‒visible absorption spectrum was measured using a Shimadzu UV‒Vis spectrophotometer UV-3600 with quartz cuvettes. The fluorescence spectra were recorded using an Edinburgh FLS980 fluorescence spectrophotometer. The relativity measurements and in vivo magnetic resonance imaging were conducted using a 3 T animal MRI scanner (MRS 3000, MR Solution, Guidfore, United Kingdom). Fluorescence imaging was obtained using the IVIS Spectrum imaging system (PerkinElmer, Inc.).

The Fourier transform–infrared (FT–IR) spectra of the CQD samples were recorded on a FT–IR spectrophotometer (VERTEX 80V, Karlsruhe, Germany). Nuclear magnetic resonance (NMR) spectra (¹H, ¹³C and 2D-HSQC) of CQD samples dissolved in D₂O were recorded using a Bruker Avance 600 MHz spectrometer (Karlsruhe, Germany). Visual structures of each CQD sample was examined by transmission electron microscopy (TEM) using a JEM 2100 transmission electron microscope (JEOL Ltd., Tokyo, Japan). CQD photoluminescent spectra were recorded using FLS980 fluorescence spectrophotometer (Edinburgh Instruments, Ltd., Livingston, UK) in aqueous solution. The quantum yield of the CQD samples were determined at an excitation wavelength of 360 nm, using quinine sulfate as the reference. X-ray photoelectron spectroscopy (XPS) spectra of CQD samples were also acquired using an Ultima IV spectrometer (Rigaku, Japan).

UV-visible absorption spectra were measured by a Shimadzu UV-3600Plus UV-VIS-NIR spectrometer. Excitation and emission spectra were recorded on Edinburgh FLS980 fluorescence spectrophotometer. Luminescence lifetimes were obtained on a single photon counting spectrometer from Edinburgh FLS980 with laser lamp as the excitation source. The data were analyzed by tail fit of the decay profile using a software package provided by Edinburgh Instruments. Absolute photoluminescence quantum yields (PLQYs) were measured using Hamamatsu C9920-02 photoluminescence quantum yield measurement system with integrating sphere.
The photophysical properties of the complexes were all measured in nitrogen atmosphere. Specifically, the solution of the complexes was prepared and sealed into quartz cells in a glove box for measuring spectra, exited state lifetimes and PLQYs. The solid powder of the complexes was sandwiched between two quartz slices and sealed the edges of the quartz slices with paraffin in a glove box for measuring spectra and excited state lifetimes. The integrating sphere was transferred into a glove box, and the solid powder of the complexes was put into matching quartz cells for measuring PLQYs. All measurements were performed at room temperature.

All ¹H-NMR spectra were obtained on Bruker AVANCE III 400 MHz or 500 MHz NMR spectrometers (Q. One Instruments Ltd.). Multiplicity was indicated as follows: s (singlet), d (doublet), t (triplet), m (multiple), dd (doublet of doublets). All coupling constants (J) are reported in Hertz (Hz). Mass spectra were in general recorded on QSTAR Elite (ABI). A UV-3100PC spectrophotometer (MAPADA) with background correction was applied to measure the optical absorption spectra. NIR-II Fluorescence spectrophotometry was performed with an Edinburgh instrument FLS980 fluorescence spectrophotometer. Transmission electron microscopy (TEM) images were acquired through DTM-961002 of JEOL Ltd. Atomic Force Microscopy (AFM) images were acquired through Bruker ICON-XR. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed on the American BIO-RAD electrophoresis system.