We present the generation of whispering gallery magnons with unprecedented high wave vectors via nonlinear 3-magnon scattering in a μm-sized magnetic Ni_{81}Fe_{19} disc which is in the vortex state. ...These modes exhibit a strong localization at the perimeter of the disc and practically zero amplitude in an extended area around the vortex core. They originate from the splitting of the fundamental radial magnon modes, which can be resonantly excited in a vortex texture by an out-of-plane microwave field. We shed light on the basics of this nonlinear scattering mechanism from an experimental and theoretical point of view. Using Brillouin light scattering microscopy, we investigated the frequency and power dependence of the 3-magnon splitting. The spatially resolved mode profiles give evidence for the localization at the boundaries of the disc and allow for a direct determination of the modes wave number.
Focusing light deep inside living tissue has not been achieved despite its promise to play a central role in biomedical imaging, optical manipulation and therapy. To address this challenge, ...internal-guide-star-based wavefront engineering techniques--for example, time-reversed ultrasonically encoded (TRUE) optical focusing--were developed. The speeds of these techniques, however, were limited to no greater than 1 Hz, preventing them from in vivo applications. Here we improve the speed of optical focusing deep inside scattering media by two orders of magnitude, and focus diffuse light inside a dynamic scattering medium having a speckle correlation time as short as 5.6 ms, typical of living tissue. By imaging a target, we demonstrate the first focusing of diffuse light inside a dynamic scattering medium containing living tissue. Since the achieved focusing speed approaches the tissue decorrelation rate, this work is an important step towards in vivo deep tissue noninvasive optical imaging, optogenetics and photodynamic therapy.
Ye J, Li R, Cheng J, et al. Int J Nanomedicine. 2022;17:6047-6064. The authors have advised that there is an error in Figure 9 on page 6060 of the published paper. Due to an error that occurred ...inadvertently at the time of figure assembly, figure part D is incorrect. Although it does not affect the conclusion that AmB nanoformulations can significantly promote macrophage proliferation when incubated with high concentrations, it is an obvious mistake. The correct Figure 9 is as follows. Figure 9 Continued. Figure 9 In vitro cytotoxicity of AmB injection, AmB-CSC, and AmB-Lipo in murine RAW264.7 macrophages. The murine RAW264.7 macrophages were treated with AmB injection (A), AmB-CSC (C), and AmB-Lipo (E) at AmB concentrations of 0.1-50 µg/mL for 24 h and the cell viability was determined using CCK-8 kits. Each value represents the mean ± SEM (n = 6). ***p < 0.001 compared with the control (Ctrl) group. The cell morphology of RAW264.7 macrophages after incubation with AmB injection (B), AmB-CSC (D), and AmB-Lipo (F) was observed by Cell Imaging Multimode Reader (Cytation 5, BioTek).Abbreviations: AmB, amphotericin B; AmB-CSC, AmB cholesteryl sulfate complex; AmB-Lipo, AmB liposome; SEM, standard error of the mean. The authors apologise for this error.
Dynamic light scattering (DLS), also known as photon correlation spectroscopy (PCS), is a very powerful tool for studying the diffusion behaviour of macromolecules in solution. The diffusion ...coefficient, and hence the hydrodynamic radii calculated from it, depends on the size and shape of macromolecules. In this review, we provide evidence of the usefulness of DLS to study the homogeneity of proteins, nucleic acids, and complexes of protein–protein or protein–nucleic acid preparations, as well as to study protein–small molecule interactions. Further, we provide examples of DLS’s application both as a complementary method to analytical ultracentrifugation studies and as a screening tool to validate solution scattering models using determined hydrodynamic radii.
Conventional light diffusers have periodic surface profiles, periodic refractive index distributions, or light scattering layers containing colloids. In all such structures the optical directivity of ...the light diffuser is cannot typically be controlled. Here we propose an electrically tunable light diffuser based on the application of ultrasound to a nematic liquid crystal (LC) material. The ultrasonic LC diffuser consists of an LC layer sandwiched by two glass discs and an ultrasonic transducer. The electrodes of the transducer are divided in a circumferential direction so that a resonant non-coaxial flexural vibration mode can be generated on the diffuser by controlling the electrical input signals. A continuous reversed-phase sinusoidal electric signal to the transducer generates the non-coaxial resonant flexural vibration mode on the glass disc, inducing an acoustic radiation force acting on the boundary between the LC layer and glass discs. This effect changes the molecular orientation of the LC and the transmitted light distribution. The diffusion angle of the transmitted light depends on the input voltage amplitude, and the diffusion angle was maximized at 16.0 V. The vibrational distribution and the diffusion directivity could be rotated by adjusting the input voltages to different electrodes, meaning that an ultrasonic LC diffuser with a thin structure and no moving mechanical parts provided a tunable light-diffusing functionality with rotatable directivity.
This paper presents an approach for label-free brain tumor tissue typing. For this application, our dual modality microspectroscopy system combines inelastic Raman scattering spectroscopy and Mie ...elastic light scattering spectroscopy. The system enables marker-free biomedical diagnostics and records both the chemical and morphologic changes of tissues on a cellular and subcellular level. The system setup is described and the suitability for measuring morphologic features is investigated.
Graphical Abstract
Bimodal approach for label-free brain tumor typing. Elastic and inelastic light scattering spectra are collected laterally resolved in one measurement setup. The spectra are investigated by multivariate data analysis for assigning the tissues to specific WHO grades according to their malignancy
Human islet amyloid polypeptide (hIAPP, or amylin) forms amyloid deposits in the islets of Langerhans, a phenomenon that is associated with type‐2 diabetes impacting millions of people worldwide. ...Accordingly, strategies against hIAPP aggregation are essential for the prevention and eventual treatment of the disease. Here, it is shown that generation‐3 OH‐terminated poly(amidoamine) dendrimer, a polymeric nanoparticle, can effectively halt the aggregation of hIAPP and shut down hIAPP toxicity in pancreatic MIN6 and NIT‐1 cells as well as in mouse islets. This finding is supported by high‐throughput dynamic light scattering experiment and thioflavin T assay, where the rapid evolution of hIAPP nucleation and elongation processes is halted by the addition of the dendrimer up to 8 h. Discrete molecular dynamics simulations further reveal that hIAPP residues bound strongly with the dendrimer near the c‐terminal portion of the peptide, where the amyloidogenic sequence (residues 22–29) locates. Furthermore, simulations of hIAPP dimerization reveal that binding with the dendrimer significantly reduces formation of interpeptide contacts and hydrogen bonds, thereby prohibiting peptide self‐association and amyloidosis. This study points to a promising nanomedicinal strategy for combating type‐2 diabetes and may have broader implications for targeting neurological disorders whose distinct hallmark is also amyloid fibrillation.
Inhibition of human islet amyloid polypeptide (hIAPP) aggregation and cytotoxicity by G3 hydroxyl‐terminated polyamidoamine dendrimer is shown. Discrete molecular dynamics simulations illustrate that binding with a dendrimer (ball representation) inhibits the association of amyloidogenic sequences between two hIAPP peptides. High‐throughput dynamic light scattering shows inhibited hIAPP aggregation over time. Reduced hIAPP toxicity in MIN6 cells treated with the dendrimer than the control.
We described a novel resonance light scattering (RLS) sensor for the specific recognition of trace quantities of Hepatitis A Virus (HAV); the sensor was based on a mussel-inspired hepatitis ...molecularly imprinted polymer. As a recognition element, polydopamine (PDA)-coated totivirus-imprinted polymer was introduced on the surface of SiO2 nanoparticles (virus-imprinted SiO2@PDA NPs) using an efficient one-step synthesis method. The target virus was selectively captured by the imprinted polymer films, thereby increasing the RLS intensity. A simple fluorescence spectrophotometer was employed to measure the changes in the intensity. The enhanced RLS intensity (∆IRLS) was proportional to the concentration of HAV in the range of 0.04–6.0nmol∙L−1, with a low limit of detection of 8.6pmol∙L−1. The selectivity study confirmed that the resultant HAV-imprinted SiO2@PDA NPs possessed high selectivity for HAV. The sensor was successfully applied for the direct detection of additional HAV from a 20,000-fold dilution of human serum. The proposed strategy is simple, eco-friendly, highly selective, and sensitive.
•A novel strategy for detection of HAV based on MIPs-RLS sensor is proposed.•The strategy broadens the applicability of the RLS technique to the detection of macromolecules virus.•The proposed strategy is simple, eco-friendly, highly selective and highly sensitive.
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