Alpha 2 spectrometer

The presence of capping agents and specific functional groups responsible for the fabrication of the AgNPs and KNC were determined by FTIR analysis^{39 (link)}. The samples were centrifuged to remove any residues and then, re-suspended in distilled water. The spectra were obtained using an ALPHA II spectrometer, (Bruker) in the wave number region of 4000–500 cm⁻¹ with 15 scans at a resolution of 2 cm⁻¹ at transmission mode.

THF, Et₂O, toluene and hexane were passed through columns containing molecular sieves, then stored over molecular sieves (THF) or over a potassium mirror (Et₂O, hexane, toluene) and thoroughly degassed prior to use. Anhydrous benzene was purchased from Sigma Aldrich, stored over a potassium mirror and thoroughly degassed prior to use. For NMR spectroscopy, C₆D₆ and C₄D₈O were dried by refluxing over K, CDCl₃ was dried by refluxing over CaH₂; NMR solvents were then vacuum transferred and degassed by three freeze-pump-thaw cycles before use. NMR spectra were recorded on either a Bruker AVIII HD 400 or Bruker AVIII 500 spectrometer operating at 400.07/500.13 (¹H), 100.60/125.78 (¹³C{¹H}), 376.46 (¹⁹F{¹H}) MHz. NMR spectra were recorded at 298 K unless otherwise stated and were referenced to residual solvent signals in the case of ¹H and ¹³C{¹H} experiments. FTIR spectra were recorded on a Bruker Alpha II spectrometer with a Platinum-ATR module. Elemental microanalyses were carried out by Elemental Microanalysis Ltd. Lawson’s reagent, 6-trifluoromethyl-2-pyridone, 2-mercaptopyridine, potassium hydroxide, bromoform, isopropylmagnesium chloride, methylmagnesium bromide, and methylmagnesium iodide were used as received. HTptm [25 (link)], 2-mercapto-6-trifluoromethylpyridine [32 (link)], and benzyl potassium [33 (link)] were prepared according to literature procedures.

The heads and thoraces of the individual mosquitoes were scanned using attenuated total reflection-Fourier transform infrared (ATR-FTIR) ALPHA II spectrometer (Bruker Optics), as previously described [20 (link), 23 (link), 25 (link)]. The mid-infrared spectra were recorded at 4000 cm⁻¹ to 400 cm⁻¹ frequencies with a spectral resolution of 2 cm⁻¹. To have noise-free spectra and optimize performance of the spectrometer, 32 background scans were performed without a sample, and the procedure was repeated after every 20 individual sample scans.
Scanning of the mosquito samples was done at the VectorSphere, where the spectrometer is installed. Before scanning, ethanol-preserved samples were placed on paper towels to allow evaporation of the liquid (Fig. 1). The procedure was also performed on mosquito samples that had been frozen to allow the moisture to evaporate. The proprietary Bruker-OPUS software version 7.5 was used to record and process the MIR spectra. At least 203 mosquitoes were used for each age (5 and 17 days old), each storage duration (1, 4, and 8 weeks), and each preservation method (silica, freezing, and ethanol (Table 1).

The chemical characterization of all scaffolds was performed using FTIR on a Bruker Alpha II spectrometer (Großweikersdorf, Austria) using a transmission geometry. Samples were obtained as KBr pellets with a concentration of 0.2% w/w, and measurements were performed at room temperature, with the spectra being recorded within the range 400–4000 cm⁻¹ (scan time of 24 and resolution of 4 cm⁻¹).

The calcinated samples were subjected to structural, morphological, and luminescence studies by using different characterizing tools such as Powder X-ray diffraction (PXRD) patterns of MgO NPs were recorded using XPERT-3, PXRD instrument (Panalytic-make) using CuKα radiation of wavelength 1.54 nm, in the 2θ range of 20°–80°. Fourier transform infrared spectroscopy (FTIR) spectra were recorded in the range of 500–4,000 cm⁻¹ using an alpha II spectrometer (Bruker -make). Surface morphology was analyzed using a Scanning electron (SEM) microscope (VEGA3 LMU). Absorption spectra were analyzed by Evolution 201 UV-visible spectrometer instrument (Thermo scientific–make) recorded in the range of 200–800 nm. Gamma irradiation in the dose range 10–50 KGy was done using Co-60 (BRIT-make) before TL studies and TL reading was recorded in the temperature range of 40°C–450°C at a heating rate of 2.5 Cs⁻¹ using TL 1009I reader (Nucleonix-make).

The optical properties of AuNRs and AuNRs-C₁₂ in DMSO were evaluated by a double beam spectrophotometer (Shimadzu UV-2401PC) in the range of 350–900 nm. AuNRs-C₁₂ and 12-MDA were analyzed by FT-IR spectroscopy (Bruker Alpha II spectrometer) in KBr pellets. In particular, to obtain a solid sample of AuNRs-C₁₂, the organic dispersion was dialyzed (MWCO 12–14 kDa) for two days against ultrapure water and then freeze-dried. The FT-IR spectra were recorded in the range of 400–4000 cm⁻¹ (scan times: 24; resolution: 4 cm⁻¹).
The elemental analysis was carried out with SEM Phenom XL ProX, a scanning electron microprobe.