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The characterization of dispersions, suspensions, and emulsions is important in a wide range of scientific and industrial applications. Samples may consist of different materials with a wide range of particle sizes and concentrations. In a technology transfer project with LUM GmbH, a single particle sizing and counting instrument with a dynamic detection range of ≥6 decades has been developed to...

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An independent international group of researchers from academics and national agencies formed a dedicated task group within the American Association of Physicists in Medicine to identify key image quality characteristics and objective test methods for macroscopic fluorescence-guided surgery (FGS). The minimum set of measurements considered important for basic device performance are image sharpness,...

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On September 27, 2023, PTB Berlin hosted the kick-off meeting of the EU project GenomeMET. Cancer is a major challenge in Europe, causing more than 1.3 million deaths annually. EU-Mission Cancer prioritizes early diagnosis and precision medicine. Advances in gene sequencing, driven by technologies such as Next Generation Sequencing (NGS), are transforming cancer care. These techniques promise...

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An optical flow cytometer analyzes and counts cells and particles based on the measured intensity of their scattered light, among other things. In recent years, however, it has become increasingly popular to image the scattered light on a camera. This allows images of cells and particles to be taken and analyzed in the forward and sideward directions. If the scattered light of spherical particles...

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Finding genetic sequences plays a key role in modern medical diagnostics. Today genetic sequences are commonly determined by next-generation-sequencing (NGS) techniques. Applications include cancer diagnostics and detection of pathogens. Such NGS techniques also lead to the discovery of the SARS-CoV-2 virus.

PTB´s Institute Berlin held a workshop “Metrology Needs for Next-Generation-Sequencing”...

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Diffuse optical imaging allows the characterization of physiological parameters of tumors in the breast. By using appropriate wavelengths in the near-infrared spectral region, the concentrations of oxygenated and deoxygenated hemoglobin, as well as water and collagen content, can be estimated. In the scanning method shown in the left figure, picosecond laser pulses are broadened by the strong...

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Fluorophores are substances that fluoresce, i.e., that emit light after prior excitation. Micro- and nanoparticles loaded with fluorophores are widely used in materials and life sciences, e.g., in fluorescence microscopy or flow cytometry. For a comparability of the measured fluorescence intensities between different instruments or laboratories, which usually provide only relative values, a...

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Proof of SARS-CoV-2 infection is based on detection of genetic markers - e.g. using PCR. The infection can also be proved by detection of characteristic proteins. Antigen tests make use of this approach. We tested the correlation between genetic markers and proteins of SARS-CoV-2. Two quantitative methods were used. The gene concentration was measured using digital PCR. This method provides most...

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SARS-CoV-2 positiv TestIn response to the high demand for rapid SARS-CoV-2 diagnostic tests, lateral flow tests have been widely used as a diagnostic tool to detect SARS-CoV-2 antigens. Compared to PCR tests, these tests are inexpensive to produce and easy to use. They provide a rapid visual result and are ideal for point-of-care settings.

We investigated the interlaboratory performance of SARS-CoV-2 antigen testing...

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Standardized technical validation of biophotonic devices is indispensable for the reliability and reproducibility of measurement results in their medical use. This requires suitable standardized phantoms, i.e., tissue-like test specimens, and recognized standards for evaluating the performance of these devices. Both prerequisites are not sufficiently met in the field of medical optical imaging. A...

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