Suprasil cuvette

UV–Vis spectroscopy characterization of AgCl/DDAC and AgCl/DDoAC NCs was performed using Shimadzu UV-1601 double beam spectrometer; all spectra were operated between 200 and 500 nm range, in with 1-cm quartz Suprasil® cuvettes from Hellma Analytics (Müllheim, Germany). X-ray photoelectron spectroscopy (XPS) measurements were performed using a PHI 5000 Versa Probe II Scanning XPS Microprobe spectrometer (ULVAC-PHI Inc., Kanagawa, Japan). The measurements were performed with a monochromatized Al Kα source (1486.6 eV, X-ray spot 200 μm), at a power of 50.3 W. Dual-beam charge neutralization was constantly applied during the analysis. Wide scans and detailed spectra were acquired in Fixed Analyzer Transmission (FAT) mode with a pass energy of 117.40 eV and 46.95 eV, respectively. An electron gun was used for charge compensation (1.0 V, 20.0 μA). The Binding Energy (BE) scale was calibrated by fixing the aliphatic component of the C1s signal (BE = 284.8 ± 0.2 eV) as a reference. Spectral processing was performed using MultiPak software v. 9.9.0.8. The modified Auger parameter (α′) was calculated as the sum of the BE (Ag3d_5/2) and the kinetic energy (KE) of the AgM₄N₄₅N₄₅ sharpest peak [46 (link)].

L-Ag NPs and L-Ag/MMT composites were analyzed with a PHI 5000 Versa Probe II Scanning XPS Microprobe spectrometer (ULVAC-PHI Inc., Kanagawa, Japan). The measurements were performed using a monochromatized Al Kα source (X-ray spot 200 µm) at power of 50.3 W. Wide scans and detailed spectra were acquired in fixed analyzer transmission (FAT) mode with pass energies of 117.40 and 46.95 eV, respectively. An electron gun was used for charge compensation (1.0 V, 20.0 µA). The binding energy (BE) scale was calibrated by fixing the aliphatic component of the C1s signal (BE = 284.8 ± 0.1 eV) as the reference. Data processing was performed by using MultiPak software v. 9.9.0.8. The absorption spectra of L-Ag, L-Ag/MMT, and MMT were measured using UV–vis spectroscopy (Shimadzu UV-1601, Duisburg, Germany), operating the spectrometer in the 220 and 800 nm range in quartz Suprasil^® cuvettes from Hellma Analytics (Müllheim, Germany). A total of 3.5 mg/mL of L-Ag/MMT was used for the UV–vis experiment.

Fluorescent properties of fluorescein-maleimide-labelled nanocomposites were analyzed using an OceanOptics Maya2000 Pro (Ocean Insight, Orlando, FL, USA) fiber optic spectrophotometer with a quasi-monochromatic LED, λmax = 365 nm (HAMAMATSU, LC1) and a long-pass filter (cut on 400 nm). Samples were prepared by placing 2.5 mL of the appropriate solution/dispersion into 10 mm Hellma™ Suprasil™ cuvettes.

In order to measure the luminescence, the sample solution was loaded into 2.0 mL quartz Suprasil cuvettes (Hellma Analytics, UK) placed within a cuvette holder (qpod 2e, Ocean Optics Inc., Liberty Lake, Washington, USA) at room temperature. The sample was illuminated with a 976 nm NIR laser (BL976‐PAG900; Thorlabs, New Jersey, USA), operating at a power corresponding to 1000 mA current. UCNP emission was recorded using a high‐performance spectrometer (QE‐PRO, Ocean Optics, Florida, USA) with 1‐second integration time and no data averaging.

Circular dichroism of 0.2 mg/mL proteins in H10Na500G5 with 1 mM EDTA, 0.1 mM CaCl₂, 1 mM CaCl₂, 10 mM CaCl₂, 100 mM CaCl₂ or 7-fold excess of TbCl₃ was measured in 1 mm quartz SUPRASIL^® cuvettes (Hellma Analytics, Müllheim, Germany) using Jasco J-815 spectropolarimeter (Jasco, Easton, MD, USA) with a Peltier temperature control accessory set at 20 °C. The proteins were incubated with the additives at room temperature for at least 1 h before the measurements. The spectra were collected between 200 and 260 nm every 1 nm at scanning speed of 50 nm/min with five accumulations. Data, for which photomultiplier voltage was below 600 V, were analyzed. CD spectra of the proteins were corrected for buffer background signal and normalized for protein composition and concentration using an equation [64 (link)]: ${\theta }_{mrw}=\frac{\theta ·MRW}{10·c·l} \left[\frac{\mathrm{deg}·{\mathrm{cm}}^2}{\mathrm{dmol}}\right]$
where ${\theta }_{mrw}$ is a mean residue ellipticity, $\theta$ —ellipticity [degrees], MRW—mean residual weight of a protein [g/mol], c—protein concentration [g/L] and l—optical pathlength of a cuvette [cm]. The secondary structure content was estimated using CDPro [65 (link)].

RNA oligonucleotides were annealed and measured at 5 μM. Annealed RNA was measured in 1 mm pathlength quartz Suprasil cuvettes (Hellma Analytics) at 25°C with a Jasco J-810 Spectropolarimeter set as follows: scan: 320-220 nm; scanning mode: continuous; speed: 100 nm/min; response: 2 s; data pitch:1; accumulation: 5. Background signal from buffer was measured and subtracted from corresponding spectra. For TMPyP4 titration experiments settings were the same as above except for the following: speed: 200 nm/minute; accumulation: 3. Successively, 1 μl aliquots of 1 mM TMPyP4 stock were added and samples were incubated at room temperature for ten minutes before measuring.