Tecnai g2 f20 microscope

Transmission electron microscope (TEM) images were obtained with a Hitachi H-7650 TEM operated at 150 kV. The high-resolution transmission electron microscope (HRTEM) images were acquired via a Philips Tecnai G2 F20 microscope at an acceleration voltage of 200 kV. Scanning electron microscope (SEM) images were obtained from a JTOL JSM-7001F microscope operated at 10 kV. UV-Vis spectra were obtained with a Shimadzu 2600 spectrometer. Zeta potentials were measured by a Malvern Nano-ZS90 Zetasizer. Raman spectra was recorded by a B&W Tek portable Raman spectrometer (i-Raman Plus BWS465-785H). All the samples were excited with a 785 nm laser, which laser power and acquisition time at each spot was 10 mW and 10 s, respectively.

Transmission electron microscopy (TEM) images were taken on a H-7650 microscope (Hitachi, Japan) at an accelerating voltage of 80 kV. High-resolution TEM (HRTEM) images of AuNRs were taken on a Tecnai G2 F20 microscope (Philips, Holland) operated at 200 kV. Zeta potentials of various nanoparticles were examined by using a Nano-ZS90 ZetaSizer (Malvern, UK). UV-vis spectra were measured with a Shimadzu 2600 spectrometer. Raman spectrum of the tested strips were measured by a portable Raman system (B&W Tek, i-Raman Plus BWS465-785H spectrometer) with 785 nm laser excitation. All samples were excited with a power of 10 mW and a total acquisition time of 10 s for each SERS spectra.

Fourier transform infrared (FT-IR) analysis was carried out using KBr discs in the region of 4000–500 cm⁻¹ by a Fourier transform infrared spectrophotometer (Shimadzu IR prestige-21, Osaka, Japan). Ultraviolet–visible (UV-Vis) absorption spectra were performed on a Lambda 750 spectrophotometer (PerkinElmer, New York, NY, USA). The photoluminescence (PL) spectra were recorded on a Shimadzu RF-5301 PC spectrofluorophotometer (Osaka, Japan). The particle sizes of NPs were obtained by a Britain Malvern PSA (NANO2590, Beijing, China) submicron particle size analyzer with angle detection at 90°. The microstructure and morphology of the NPs were examined by high-resolution transmission electron microscopy (HRTEM, Germany, Berlin) on a Philips Tecnai G2F20 microscope (Philips, Amsterdam, Netherlands) with an accelerating voltage of 200 kV. The crystal structure of the NPs was investigated by XRD (Rigaku D/MAX-2400 X-ray diffractometer with Ni-filtered Cu Kα radiation (λ = 1.54056), Osaka, Japan).