αsyn stocks  (StressMarq)

Journal: EMBO Molecular Medicine

Article Title: Alpha-synuclein misfolding as fluid biomarker for Parkinson’s disease measured with the iRS platform

doi: 10.1038/s44321-025-00229-z

Figure Lengend Snippet: ( A ) The secondary structure-sensitive Amide-I band absorbance of capture-antibody-bound αSyn-monomers (green, Stressmarq Bioscience Inc SPR-321), αSyn-oligomers (orange, Stressmarq Bioscience Inc SPR-466), and αSyn-PPFs (red, Stressmarq Bioscience Inc SPR-322) in PBS at high concentration of 500 ng/ml and scaled (x1.5–4) for comparison. Their structural differences are indicated by the significant wavenumber shift (cm −1 ) ranging from 1650 cm −1 for α-helical/random-coil (green) over 1647 cm −1 (orange) to β-sheet dominated structures absorbing at 1624 cm −1 (red). ( B ) The inertness measures on the blocking solution (BS) layer at high concentrations (500–5000 ng/ml) without the capture antibody. No signal is observed without the antibody on the blocking layer demonstrating sufficient inertness for pg-ng/ml concentrations of αSyn in CSF. αSyn alpha-synuclein, BS blocking solution, PFF pre-formed fibril. .

Article Snippet: Briefly, αSyn stocks (Stressmarq, Cat. No. SPR-321), stored at −80 °C, were slowly thawed on ice.

Techniques: Concentration Assay, Comparison, Blocking Assay

Journal: EMBO Molecular Medicine

Article Title: Alpha-synuclein misfolding as fluid biomarker for Parkinson’s disease measured with the iRS platform

doi: 10.1038/s44321-025-00229-z

Figure Lengend Snippet: A The mean ThT-excitation and emission spectra from sample triplicates, recorded from 410–460 nm and 480–620 nm and displayed in relative fluorescence units (RFUs). For this, technical triplicates of αSyn-M (Stressmarq Bioscience Inc., SPR-321), αSyn-O (Stressmarq Bioscience Inc., SPR-466), and αSyn-PFFs (Stressmarq Bioscience Inc., SPR-322) were prepared with a final concentration of 7.14 μM in 25 μM ThT-PBS buffer, incubated for 60 min at ambient temperature in the 96 F-bottom fluorescence plate and measured with the plate reader in spectral scan mode. The excitation scan was performed from 410–460 nm, while the emission scan was performed from 480–620 nm, with a bandwidth of 10 nm and 20 flashes/well. The gain was adjusted at expected maxima (453/482 nm), and autofocus obtained focal height. Before read-out, the plate was shaken at 300 rpm for 5 s. ( B ) Mean ThT intensities at 482 nm were calculated from triplicate ThT measures of the respective antigens. The ThT-emission factor was calculated with mean intensities at 482 nm by division of mean intensities of the buffer at 482 nm (25 μM ThT-PBS). Moreover, the 1630/1650-R, derived from ATR-FTIR measurement in duplicates, was plotted against the ThT factor since the increased 1630/1650-R shows increased ß-sheet content of the given protein and decreased α-helical/random-coil content. To obtain the 1630/1650-R without the influence of binding tendencies of antibodies, antigens were measured directly on the Bruker alpha ATR-FTIR cell against the respective buffer (PBS, pH 7.4). The 1650/1630-R was retrieved automatically by the same MATLAB script used for the CSF samples after averaging 10 sample spectra for increased S/N. Error bars display the standard deviation of the ATR-duplicates or ThT-triplicates.

Article Snippet: Briefly, αSyn stocks (Stressmarq, Cat. No. SPR-321), stored at −80 °C, were slowly thawed on ice.

Techniques: Fluorescence, Concentration Assay, Incubation, Derivative Assay, Binding Assay, Standard Deviation