Tm-Based Downshifting Nanoprobes with Enhanced Luminescence at 1680 nm for In Vivo Vascular Growth Monitoring.

Optical imaging in the 1500-1700 nm region, known as near-infrared IIb (NIR-IIb), shows potential for noninvasive in vivo detection owing to its ultrahigh tissue penetration depth and spatiotemporal resolution. Rare earth-doped nanoparticles have emerged as widely used NIR-IIb probes because of their excellent optical properties. However, their downshifting emissions rarely exhibit sufficient brightness beyond 1600 nm.

SERS-Encoded Nanoprobes Based on Silver-Coated Gold Nanorods for Cell Sorting.

Optically-encoded probes have great potential for applications in the fields of biosensing and imaging. By employing specific encoding methods, these probes enable the detection of multiple target molecules and high-resolution imaging within the same sample. Among the various encoding methods, surface-enhanced Raman scattering (SERS) spectral encoding stands out due to its extremely narrow linewidth.

Addressable scanning multifocal structured illumination microscopy using acousto-optic deflectors.

Multifocal structured illumination microscopy (MSIM) is a popular super-resolution imaging technique known for its good probe compatibility, low laser power requirements, and improved imaging depth, making it widely applicable in biomedical research. However, the speed of MSIM imaging is typically constrained by the approaches employed to generate and scan the laser foci across the sample. In this study, we propose a flexible two-photon excitation MSIM method using a pair of acousto-optic deflectors.

A reversible photoelectrochemical microsensor for dynamically monitoring sulfur dioxide in the epileptic brain.

Epilepsy is considered one of the most prevalent neurological disorders, yet the precise mechanisms underlying its pathogenesis remain inadequately elucidated. Emerging evidence implicates endogenous sulfur dioxide (SO) in the brain as playing a significant role in epilepsy and associated neuronal apoptosis. Consequently, tracking the dynamic fluctuations in the levels of SO and its derivatives (SO/HSO) provides valuable insights into the molecular mechanisms underlying epilepsy, with potential implications for its diagnosis and therapeutic intervention.

Polarization-resolved super-resolution second-harmonic generation imaging based on multifocal structured illumination microscopy.

Polarization-resolved second-harmonic generation (PSHG) microscopy is widely used in investigating the structural and morphological alterations of collagen. However, the resolution of second-harmonic generation (SHG) imaging remains constrained by optical diffraction, resulting in the polarization extraction of collagen characteristics from the average properties of collagen fibers. In this study, multifocal structured illumination microscopy (MSIM) was combined with PSHG to achieve polarization-resolved super-resolution imaging of second-harmonic generation signals.

In Vivo High-Contrast Biomedical Imaging in the Second Near-Infrared Window Using Ultrabright Rare-Earth Nanoparticles.

Intravital luminescence imaging in the second near-infrared window (NIR-II) enables noninvasive deep-tissue imaging with high spatiotemporal resolution of live mammals because of the properties of suppressed light scattering and diminished autofluorescence in the long-wavelength region. Herein, we present the synthesis of a downconversion luminescence rare-earth nanocrystal with a core-shell-shell structure (NaYF@NaYbF:Er,Ce@NaYF:Ca). The structure efficiently maximized the doping concentration of the sensitizers and increased Er luminescence while preventing cross relaxation.

Combination of deep learning and 2D CARS figures for identification of amyloid-β plaques.

In vivo imaging and accurate identification of amyloid-β (Aβ) plaque are crucial in Alzheimer's disease (AD) research. In this work, we propose to combine the coherent anti-Stokes Raman scattering (CARS) microscopy, a powerful detection technology for providing Raman spectra and label-free imaging, with deep learning to distinguish Aβ from non-Aβ regions in AD mice brains in vivo. The 1D CARS spectra is firstly converted to 2D CARS figures by using two different methods: spectral recurrence plot (SRP) and spectral Gramian angular field (SGAF).

Super-resolution imaging of folate receptor alpha on cell membranes using peptide-based probes.

Folate receptor alpha (FRα) is a vital membrane protein which have great association with cancers and involved in various biological processes including folate transport and cell signaling. However, the distribution and organization pattern of FRα on cell membranes remains unclear. Previous studies relied on antibodies to recognize the proteins.

Super-Resolution Second-Harmonic Generation Imaging with Multifocal Structured Illumination Microscopy.

Second-harmonic generation (SHG) is a noninvasive imaging technique that enables the exploration of physiological structures without the use of an exogenous label. However, traditional SHG imaging is limited by optical diffraction, which restricts the spatial resolution. To break this limitation, we developed a novel approach called multifocal structured illumination microscopy-SHG (MSIM-SHG).

Deep-MSIM: Fast Image Reconstruction with Deep Learning in Multifocal Structured Illumination Microscopy.

Fast and precise reconstruction algorithm is desired for for multifocal structured illumination microscopy (MSIM) to obtain the super-resolution image. This work proposes a deep convolutional neural network (CNN) to learn a direct mapping from raw MSIM images to super-resolution image, which takes advantage of the computational advances of deep learning to accelerate the reconstruction. The method is validated on diverse biological structures and in vivo imaging of zebrafish at a depth of 100 µm.

Fluorescence lifetime tracking and imaging of single moving particles assisted by a low-photon-count analysis algorithm.

Fluorescence lifetime imaging microscopy (FLIM) has been widely used in the field of biological research because of its high specificity, sensitivity, and quantitative ability in the sensing cellular microenvironment. The most commonly used FLIM technology is based on time-correlated single photon counting (TCSPC). Although the TCSPC method has the highest temporal resolution, the data acquisition time is usually long, and the imaging speed is slow.

Narrowband photoblinking InP/ZnSe/ZnS quantum dots for super-resolution multifocal structured illumination microscopy enhanced by optical fluctuation.

Cadmium-free quantum-dot (QD) fluorophores can bridge the gap between the macroscopic and microscopic domains in fluorescence super-resolution bioimaging. InP/ZnSe/ZnS QD photoblinking fluorescent probes can improve the performance of reactive super-resolution imaging techniques and spontaneously switch fluorophores between at least two states (open and close) without depending on intense laser light and specialized buffers for bioimaging. Multifocal structured illumination microscopy (MSIM) provides a two-fold resolution enhancement in sub-diffraction imaging, but higher resolutions are limited by the pattern frequency and signal-to-noise ratio.

Snapshot temporal compressive light-sheet fluorescence microscopy via deep denoising and total variation priors.

We present a snapshot temporal compressive light-sheet fluorescence microscopy system to capture high-speed microscopic scenes with a low-speed camera. A deep denoising network and total variation denoiser are incorporated into a plug-and-play framework to quickly reconstruct 20 high-speed video frames from a short-time measurement. Specifically, we can observe 1,000-frames-per-second (fps) microscopic scenes when the camera works at 50 fps to capture the measurement.

Multifunctional Hollow MnO @Porphyrin@Bromelain Nanoplatform for Enhanced Photodynamic Therapy.

Photodynamic therapy (PDT) has been showing great potential in cancer treatment. However, the efficacy of PDT is always limited by the intrinsic hypoxic tumor microenvironment (TME) and the low accumulation efficiency of photosensitizers in tumors. To address the issue, a multifunctional hollow multilayer nanoplatform (H-MnO @TPyP@Bro) comprising manganese dioxide, porphyrin (TPyP) and bromelain (Bro), is developed for enhanced photodynamic therapy.

Lipophilic Red-Emitting Carbon Dots for Detecting and Tracking Lipid Droplets in Live Cells.

Lipid droplets (LDs), a dynamic organelle, are of vital importance in regulating the storage of neutral lipids and energy homeostasis. The aberrant expression of LDs is found to be highly associated with diverse metabolic diseases. Thus, detecting and monitoring LDs are essential to study the pathological and physiological processes of LDs in living bodies.

Super-Resolution Microscopy: Shedding New Light on Imaging.

Over the past two decades, super-resolution microscopy (SRM), which offered a significant improvement in resolution over conventional light microscopy, has become a powerful tool to visualize biological activities in both fixed and living cells. However, completely understanding biological processes requires studying cells in a physiological context at high spatiotemporal resolution. Recently, SRM has showcased its ability to observe the detailed structures and dynamics in living species.

Multistage Cooperative Nanodrug Combined with PD-L1 for Enhancing Antitumor Chemoimmunotherapy.

Combinatorial CpG oligonucleotide (CPG) and chemotherapy drug represent a promising approach to reactivate immune system. However, these two agents possess different physicochemical properties, hindering the application of direct self-assembly of these two cargos into a single nanostructure. Here, a multistage cooperative nanodrug is developed by the direct self-assembly of cis-platinum (CDDP, Pt), l-arginine (l-Arg, R), and CPG (defined as PtR/CPG) for antitumor chemoimmunotherapy.

Rational design of a prodrug to inhibit self-inflammation for cancer treatment.

Photothermal therapy (PTT) has been extensively used as an effective therapeutic approach against cancer. However, PTT can trigger the proinflammatory response of dendritic cells (DCs) and macrophages to release proinflammatory cytokines, which can simulate tumor regeneration and further hinder subsequent therapy. Hence, an effective therapeutic system, comprising gold nanoparticle modified CuZnSnS nanocrystals and aspirin (Au-CZTS/Asp), was developed to co-deliver PTT agents and inflammatory inhibitors for the synergistic treatment of cancer.

Enhanced multifocal structured illumination microscopy with desired optical sectioning capability and lateral resolution improvement.

Multifocal structured illumination microscopy (MSIM) can rapidly retrieve 3D structures of thick samples by using multi-spot excitation and detection. Although numerous super-resolution (SR) and optical sectioning (OS) methods have been introduced in this field, the existing OS-SR method in MSIM still has the difficulty in rejecting deep defocused light, which may lead to strong background signal in the retrieved results. To this end, an enhanced OS-SR method is proposed to simultaneously achieve the desired OS capability and significant resolution improvement in MSIM.

Virtual single-pixel imaging-based deconvolution method for spatial resolution improvement in wide-field fluorescence microscopy.

Deconvolution technique has been widely used in fluorescence microscopy to restore fine structures of biological samples. However, conventional deconvolution methods usually achieve little contrast enhancement in dense structures that have the intervals close to the Rayleigh criterion. Herein, we developed a novel deconvolution method, termed virtual single-pixel imaging (-SPI).

Optimized approach for optical sectioning enhancement in multifocal structured illumination microscopy.

Multifocal structured illumination microscopy (MSIM) is the parallelized version of image scanning microscopy (ISM) that is created by using many excitation spots, which provides a two-fold resolution enhancement beyond the diffraction limit with a frequency of 1 Hz per 3D picture, but scattered and out-of-focus light in thick samples degrades MSIM optical sectioning performance. Herein, we introduce a new optical sectioning method in MSIM via illumination fluctuation. The proposed method suppresses the out-of-focus light by taking full advantage of the statistic property of MSIM raw data and has no requirement of changing the system setup or projecting more illumination patterns.