U 3900 uv vis spectrophotometer

Ultraviolet-visible spectrum were carried out on a HITACHI U-3900 UV-vis spectrophotometer. Fluorescence spectrum were performed on a Spectrofluorometer FS5. The IR analysis was performed with a FTIR650 spectrophotometer over the range 600–4000 cm⁻¹ at a resolution of 2 cm⁻¹. For the FESEM imaging study, A JSM-6700F FESEM instrument was used to capture the SEM images at an accelerating voltage of 10–15 kV. Meanwhile, EDS images were collected at an accelerating voltage of 15 kV. Microscopic photographs of materials are obtained through a microscope. The valence analysis of element on the film surface was collected by SCIENTIFICESCALAB 250Xi (XPS) and fitted by software. In order to study the thermal properties of the material, TG 209F4 was used to test the thermogravimetric property of the material.

The morphology and microstructure of CDs were obtained by transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) on a JEOL JEM-2010 using an accelerating voltage of 200 kV. Raman spectra were measured with HORIBA Scientific LabRAM HR Evolution (785 nm laser). Fourier transform infrared (FTIR) analysis of CDs was carried out in the form of KBr pellets with a BRUKER TENSOR 27 spectrometer. The elemental analysis (EA) of CDs was conducted on an ELEMENTAR Vario EL/micro cube. The X-ray photoelectron spectroscopy (XPS) spectra of samples were recorded on a Kratos AXIS ULTRA DLD X-ray photoelectron spectrometer with an exciting source of Al Kα = 1486.6 eV. UV-visible (UV-vis) absorption analysis was obtained using a Hitachi U3900 UV-vis spectrophotometer. The photoluminescence (PL) spectra were recorded using a Horiba Fluoromax-4 luminescence spectrometer equipped with a Xe lamp as excitation source. The fluorescence decay status and fluorescence lifetime of CDs were measured by an Edinburgh F980 Transient Fluorescence & Phosphorescence spectrometer.

The morphology and size dispersion of hybrid microgels were probed by transmission electron microscopy (TEM; JEM-2100, JEOL, Japan) at an accelerating voltage of 200 kV. Elemental mapping and high-angle annular dark field scanning TEM (HAADF-STEM) imaging were conducted using field emission transmission electron microscopy (FE-TEM) coupled with energy-dispersive X-ray spectroscopy (EDX) (Tecnai G2 F20, FEI, USA). UV-Vis spectra were recorded on a U-3900 UV-Vis spectrophotometer equipped with a temperature controller (Hitachi, Japan). Infrared spectra were recorded on an Avatar 360 Fourier transform infrared (FT-IR) spectrometer (Nicolet, USA) using the KBr pellet technique. Thermal stabilities were determined using a Q1000DSC+LNCS+FACS Q600SDT thermogravimetric analyzer (TA, USA) at a heating rate of 10 °C min⁻¹ in an atmosphere of N₂. Swelling behavior was characterized by dynamic light scattering measurements (Nano-ZS90, Malvern, UK) in the temperature range of 25–45 °C. Crystal structures were determined by X-ray diffraction (XRD) analysis (D/MAX-3C, Rigaku, Japan) performed using Cu K_α radiation at 35 kV and 40 mA. Surface compositions were determined by X-ray photoelectron spectroscopy (XPS; AXIS ULTRA, Kratos Analytical Ltd., Japan) using monochromatic Al K_α radiation.

All reagents used in the experiments were of analytical grade. HS-PEG-OCH₃ (MW 2000) was obtained from Sigma Aldrich, and 3,3'-dithio (succinimidylpropionate) (DTSP) was purchased from Heowns (Tianjin, China). Gold (III) chloride trihydrate (HAuCl₄•3H₂O) and hydroxylammonium chloride were purchased from Aladdin (Shanghai, China). Trisodium citrate was purchased from Alfa Aesar (Tianjin, China). All antibodies were obtained from Abcam (Shanghai, China). Raman dyes were purchased from Sanbang Reagent Co., Ltd. (Changchun, China). Deionized water (Milli-Q grade, Millipore) with a resistivity of 18.2 MΩ•cm was used throughout the experiment. A JEOL 1400 TEM model operating at an accelerating voltage of 100 kV was employed to capture TEM images in this study. A Hitachi U-3900 UV-vis spectrophotometer was used to record the absorbance spectrum of AuNP solutions. Dynamic light scattering (DLS) was performed on a Zeta Sizer Nano ZS (Malvern Zetasizer 300HS and He/Ne laser at 632.8 nm at scattering angles of 90 at 25 °C). A Renishaw in Via Raman microscope was used to record the Raman spectrum through the experiments. The Raman spectra of a solution was measured in capillary tubes with average length of 10 cm and diameter of 0.5 mm. Briefly, a 633 nm laser was used for sample excitation in all experiments.