Single-cell viability assessment with a novel spectro-imaging system

High-spatial density snapshot imaging spectrometer enabled by 2-photon fabricated custom fiber bundles

We report on a proof-of-concept snapshot imaging spectrometer developed using an array of optical fibers fabricated with 2-photon polymerization (2PP). The dense input array maps to an output array with engineered void spaces for spectral information. Previously, the development and fabrication of custom fiber arrays for imaging spectrometers have been a complex, time-consuming, and costly process, requiring a semi-manual assembly of commercial components. This work applies an automatic development process based on 2PP additive manufacturing with the Nanoscribe GmbH Quantum X system. The technique allows printing of arbitrary optical quality structures with submicron resolution with less than 5 nm roughness, enabling small core fibers/integrated arrays. Specifically, we developed an array prototype of 40 × 80 with 6-micron pitch at the input and 80-micron pitch at the output. The air-clad fibers had a core diameter of 5 µm. Fabricated optical fiber arrays were incorporated into a prism-based imaging spectrometer system with 48 spectral channels to demonstrate multi-spectral imaging. Imaging of a USAF target and color printed letter C as well as spectral comparisons to a commercial spectrometer were used to validate the performance of the system. These results clearly demonstrate the functionality and potential applications of the 3D-printed fiber-based snapshot imaging spectrometer.

Enhancing scanning electrochemical microscopy's potential to probe dynamic co-culture systems via hyperspectral assisted-imaging

Precise determination of boundaries in co-culture systems is difficult to achieve with scanning electrochemical microscopy alone. Thus, biological scanning electrochemical microscope platforms generally consist of a scanning electrochemical microscope positioner mounted on the stage of an inverted microscope for correlated electrochemical and optical imaging. Use of a fluorescence microscope allows for site-specific fluorescence labeling to obtain more clearly resolved spatial and electrochemical data. Here, we construct a unique hyperspectral assisted-biological scanning electrochemical microscope platform to widen the scope of biological imaging. Specifically, we incorporate a variable fluorescence bandpass source into a biological scanning electrochemical microscope platform for simultaneous optical, spectral, and electrochemical imaging. Not only does this platform serve as a cost-effective alternative to white light laser imaging, but additionally it provides multi-functional analysis of biological samples. Here, we demonstrate the efficacy of our platform to discern the electrochemical contribution of site-specific cells by optically and spectroscopically resolving boundaries as well as cell types within a complex biological system.

Combination of Structured Illumination Microscopy with Hyperspectral Imaging for Cell Analysis

Existing structured illumination microscopy (SIM) allows super-resolution live-cell imaging in few color channels that provide merely morphological information but cannot acquire the sample spectrum that is strongly relevant to the underlying physicochemical property. We develop hyperspectral SIM which enables high-speed spectral super-resolution imaging in SIM for the first time. Through optically mapping the three-dimensional (x, y, and λ) datacube of the sample to the detector plane, hyperspectral SIM allows snapshot spectral imaging of the SIM raw image, detecting the sample spectrum while retaining the high-speed and super-resolution characteristics of SIM. We demonstrate hyperspectral SIM imaging and reconstruct a datacube containing 31 super-resolution images of different wavelengths from only 9 exposures, achieving a 15 nm spectral resolution. We show time-lapse hyperspectral SIM imaging that achieves an imaging speed of 2.7 s per datacube-31-fold faster than the existing wavelength scanning strategy. To demonstrate the great prospects for further combining hyperspectral SIM with various spectral analysis methods, we also perform spectral unmixing of the hyperspectral SIM result while imaging the spectrally overlapped sample.

Snapshot multidimensional photography through active optical mapping

Multidimensional photography can capture optical fields beyond the capability of conventional image sensors that measure only two-dimensional (2D) spatial distribution of light. By mapping a high-dimensional datacube of incident light onto a 2D image sensor, multidimensional photography resolves the scene along with other information dimensions, such as wavelength and time. However, the application of current multidimensional imagers is fundamentally restricted by their static optical architectures and measurement schemes—the mapping relation between the light datacube voxels and image sensor pixels is fixed. To overcome this limitation, we propose tunable multidimensional photography through active optical mapping. A high-resolution spatial light modulator, referred to as an active optical mapper, permutes and maps the light datacube voxels onto sensor pixels in an arbitrary and programmed manner. The resultant system can readily adapt the acquisition scheme to the scene, thereby maximising the measurement flexibility. Through active optical mapping, we demonstrate our approach in two niche implementations: hyperspectral imaging and ultrafast imaging.

Multidimensional photography has traditionally been restricted by their static optical architectures and measurement schemes. Here, the authors present a tunable multidimensional photography approach employing active optical mapping, which allows them to adapt the acquisition schemes to the scene.

Punching holes in light: recent progress in single-shot coded-aperture optical imaging

Single-shot coded-aperture optical imaging physically captures a code-aperture-modulated optical signal in one exposure and then recovers the scene via computational image reconstruction. Recent years have witnessed dazzling advances in various modalities in this hybrid imaging scheme in concomitant technical improvement and widespread applications in physical, chemical and biological sciences. This review comprehensively surveys state-of-the-art single-shot coded-aperture optical imaging. Based on the detected photon tags, this field is divided into six categories: planar imaging, depth imaging, light-field imaging, temporal imaging, spectral imaging, and polarization imaging. In each category, we start with a general description of the available techniques and design principles, then provide two representative examples of active-encoding and passive-encoding approaches, with a particular emphasis on their methodology and applications as well as their advantages and challenges. Finally, we envision prospects for further technical advancement in this field.

Absorbance spectra of the hematochrome-like granules and eyespot of Euglena gracilis by scan-free absorbance spectral imaging A(x, y, λ) within the live cells

Euglena gracilis has an organelle resembling hematochrome, with an appearance similar to the eyespot and the absorption band spectrally overlapped with that of the carotenoid. To discriminate the hematochrome-like granules and eyespot, scan-free, non-invasive, absorbance spectral imaging A(x, y, λ) microscopy of single live cells, where A(x, y, λ) means absorbance at a position (x, y) on a two-dimensional image at a specific wavelength λ was applied. This technique was demonstrated to be a powerful tool for basic research on intracellular structural analysis. By this method, characteristic absorption spectra specific to the hematochrome-like granule or eyespot were identified among a variety of spectra observed depending on the location inside the organelles. The hematochrome-like granule was dark orange and deep green in its outline and had a characteristic absorption peak at 620 nm as well as at 676 to 698 nm, suggesting that its origin is a component of chloroplast including chlorophyll a. Furthermore, the representative spectra of these organelles were derived by principal component analysis of the absorbance and its position in absorbance image, indicating that they can be distinguished from each other and other regions. It was also confirmed that even in areas where these organelles and chloroplasts overlap, one can distinguish them from each other. The present research clarified the absorption spectra of the eyespot with 1 × 1 µm spatial resolution and those unpublished of hematochrome-like granules of E. gracilis, and indicated that one can statistically distinguish these organelles by this method.

High-Speed Hyperspectral Video Acquisition By Combining Nyquist and Compressive Sampling

We propose a novel hybrid imaging system to acquire 4D high-speed hyperspectral (HSHS) videos with high spatial and spectral resolution. The proposed system consists of two branches: one branch performs Nyquist sampling in the temporal dimension while integrating the whole spectrum, resulting in a high-frame-rate panchromatic video; the other branch performs compressive sampling in the spectral dimension with longer exposures, resulting in a low-frame-rate hyperspectral video. Owing to the high light throughput and complementary sampling, these two branches jointly provide reliable measurements for recovering the underlying HSHS video. Moreover, the panchromatic video can be used to learn an over-complete 3D dictionary to represent each band-wise video sparsely, thanks to the inherent structural similarity in the spectral dimension. Based on the joint measurements and the self-adaptive dictionary, we further propose a simultaneous spectral sparse (3S) model to reinforce the structural similarity across different bands and develop an efficient computational reconstruction algorithm to recover the HSHS video. Both simulation and hardware experiments validate the effectiveness of the proposed approach. To the best of our knowledge, this is the first time that hyperspectral videos can be acquired at a frame rate up to 100fps with commodity optical elements and under ordinary indoor illumination.

A High Throughput Integrated Hyperspectral Imaging and 3D Measurement System

Hyperspectral and three-dimensional measurements can obtain the intrinsic physicochemical properties and external geometrical characteristics of objects, respectively. The combination of these two kinds of data can provide new insights into objects, which has gained attention in the fields of agricultural management, plant phenotyping, cultural heritage conservation, and food production. Currently, a variety of sensors are integrated into a system to collect spectral and morphological information in agriculture. However, previous experiments were usually performed with several commercial devices on a single platform. Inadequate registration and synchronization among instruments often resulted in mismatch between spectral and 3D information of the same target. In addition, using slit-based spectrometers and point-based 3D sensors extends the working hours in farms due to the narrow field of view (FOV). Therefore, we propose a high throughput prototype that combines stereo vision and grating dispersion to simultaneously acquire hyperspectral and 3D information. Furthermore, fiber-reformatting imaging spectrometry (FRIS) is adopted to acquire the hyperspectral images. Test experiments are conducted for the verification of the system accuracy, and vegetation measurements are carried out to demonstrate its feasibility. The proposed system is an improvement in multiple data acquisition and has the potential to improve plant phenotyping.

Multiplexed Optical Imaging of Tumor-Directed Nanoparticles: A Review of Imaging Systems and Approaches

In recent decades, various classes of nanoparticles have been developed for optical imaging of cancers. Many of these nanoparticles are designed to specifically target tumor sites, and specific cancer biomarkers, to facilitate the visualization of tumors. However, one challenge for accurate detection of tumors is that the molecular profiles of most cancers vary greatly between patients as well as spatially and temporally within a single tumor mass. To overcome this challenge, certain nanoparticles and imaging systems have been developed to enable multiplexed imaging of large panels of cancer biomarkers. Multiplexed molecular imaging can potentially enable sensitive tumor detection, precise delineation of tumors during interventional procedures, and the prediction/monitoring of therapy response. In this review, we summarize recent advances in systems that have been developed for the imaging of optical nanoparticles that can be heavily multiplexed, which include surface-enhanced Raman-scattering nanoparticles (SERS NPs) and quantum dots (QDs). In addition to surveying the optical properties of these various types of nanoparticles, and the most-popular multiplexed imaging approaches that have been employed, representative preclinical and clinical imaging studies are also highlighted.

No-scanning 3D measurement method using ultrafast dimensional conversion with a chirped optical frequency comb

A simultaneously high-precision, wide-range, and ultrafast time-resolution one-shot 3D shape measurement method is presented. Simultaneous times of flight from multiple positions to a target encoded in a chirped optical frequency comb can be obtained from spectral interferometry. We experimentally demonstrate a one-shot imaging profile measurement of a known step height of 480 µm with µm-level accuracy. We further demonstrate the extension of the dynamic range by measuring in one shot a large step height of 3 m while maintaining high accuracy using the accurate pulse-to-pulse separation of the optical frequency comb. The proposed method with its large dynamic range and measurement versatility can be applied to a broad range of applications, including microscopic structures, objects with large size or aspect ratio, and ultrafast time-resolved imaging. This study provides a powerful and versatile tool for 3D measurement, where various ranges of measurement performances can be tailored to demand.

A review of snapshot multidimensional optical imaging: measuring photon tags in parallel

Multidimensional optical imaging has seen remarkable growth in the past decade. Rather than measuring only the two-dimensional spatial distribution of light, as in conventional photography, multidimensional optical imaging captures light in up to nine dimensions, providing unprecedented information about incident photons' spatial coordinates, emittance angles, wavelength, time, and polarization. Multidimensional optical imaging can be accomplished either by scanning or parallel acquisition. Compared with scanning-based imagers, parallel acquisition-also dubbed snapshot imaging-has a prominent advantage in maximizing optical throughput, particularly when measuring a datacube of high dimensions. Here, we first categorize snapshot multidimensional imagers based on their acquisition and image reconstruction strategies, then highlight the snapshot advantage in the context of optical throughput, and finally we discuss their state-of-the-art implementations and applications.

Scan-Free Absorbance Spectral Imaging A(x, y, λ) of Single Live Algal Cells for Quantifying Absorbance of Cell Suspensions

Label-free, non-invasive, rapid absorbance spectral imaging A(x,y,λ) microscopy of single live cells at 1.2 μm × 1.2 μm resolution with an NA = 0.85 objective was developed and applied to unicellular green algae Chlamydomonas reinhardtii. By introducing the fiber assembly to rearrange a two-dimensional image to the one-dimensional array to fit the slit of an imaging spectrograph equipped with a CCD detector, scan-free acquisition of three-dimensional information of A(x,y,λ) was realized. The space-resolved absorbance spectra of the eyespot, an orange organelle about 1 μm, were extracted from the green-color background in a chlorophyll-rich single live cell absorbance image. Characteristic absorbance change in the cell suspension after hydrogen photoproduction in C. reinhardtii was investigated to find a single 715-nm absorption peak was locally distributed within single cells. The formula to calculate the absorbance of cell suspensions from that of single cells was presented to obtain a quantitative, parameter-free agreement with the experiment. It is quantitatively shown that the average number of chlorophylls per cell is significantly underestimated when it is evaluated from the absorbance of the cell suspensions due to the package effect.

Hybrid-resolution spectral video system using low-resolution spectral sensor

This paper presents a prototype of a spectral video system based on hybrid resolution spectral imaging. The system consists of a commercial three-channel color camera and a low-resolution spectral sensor which captures a 68-pixel spectral image by a single snap-shot. By combining the measurement data from both devices, the system produces high-resolution spectral image data frame by frame. The accuracy of the spectral data measured by the system is evaluated at some selected regions in the image. As a result, it is confirmed that spectra can be measured with less or around 10% of normalized root mean squared error. In addition, the capture of spectral videos in 3 frame-per-second and the real-time color reproduction in the same frame rate from the spectral video are demonstrated.

Prism-based spectral imaging of four species of single-molecule fluorophores by using one excitation laser

A prism-based imaging system for simultaneously detecting four species of single-molecule (SM) fluorophores was developed. As for the detection method, four spectrally distinct species of BigDye fluorophores were bound to 50-nm-diameter gold nanoparticles (AuNPs) to form AuNP/BigDye complexes. Four species of complexes were randomly immobilized on different fused-silica slides. BigDyes were excited by an argon-ion-laser (excitation wavelengths: 488 and 514.5 nm) beam through total internal reflection on the slide surface. SM fluorescence emitted from a complex was spectrally dispersed through a prism to form an SM spot elongated in the spectral direction on a charge-coupled device. A scattered light spot generated by the AuNP of the same complex under 594-nm laser illumination was used as a wavelength reference, and the SM fluorescence spectrum was obtained from the pixel-intensity pattern of the elongated SM spot. Peak locations of fluorescence spectra of all the observed SM spots were obtained, and their histograms were distinctly separated according to species. SM spots can thus be classified as one of four species according to their peak locations. By statistically analyzing the histograms, the classification accuracy was estimated to be above 93.8 %. The number of pixels in the spectral direction required for classifying four species of SM fluorophores was estimated to be 10. As for the conventional system (which uses two excitation lasers), 15 pixels are required. Using BigDyes as the four fluorophores (which consist of donors linked to acceptors and can be excited by just an argon-ion laser) is the reason that such a small number of pixels was achieved. The developed system can thus detect 1.5 times more SM fluorophores per field of view; that is, its throughput is 1.5 times higher. The approach taken in this study, namely, using BigDye with a prism-type system, is effective for increasing the throughput of DNA microarray-chip analysis and SM real-time DNA sequencing.

Hyperspectral fluorescence microfluidic (HFM) microscopy

We present an imaging system that collects hyperspectral images of cells travelling through a microfluidic channel. Using a single monochrome camera and a linear variable bandpass filter (LVF), the system captures a bright field image and a set of hyperspectral fluorescence images for each cell. While the bandwidth of the LVF is 20 nm, we have demonstrated that we can determine the peak wavelength of a fluorescent object's emission spectrum with an accuracy of below 3 nm. In addition, we have used this system to capture fluorescence spectra of individual spatially resolved cellular organelles and to spectrally resolve multiple fluorophores in individual cells.

Image mapping spectrometry: calibration and characterization

Image mapping spectrometry (IMS) is a hyperspectral imaging technique that simultaneously captures spatial and spectral information about an object in real-time. We present a new calibration procedure for the IMS as well as the first detailed evaluation of system performance. We correlate optical components and device calibration to performance metrics such as light throughput, scattered light, distortion, spectral image coregistration, and spatial/spectral resolution. Spectral sensitivity and motion artifacts are also evaluated with a dynamic biological experiment. The presented methodology of evaluation is useful in assessment of a variety of hyperspectral and multi-spectral modalities. Results are important to any potential users/developers of an IMS instrument and to anyone who may wish to compare the IMS to other imaging spectrometers.

Real-time snapshot hyperspectral imaging endoscope

Hyperspectral imaging has tremendous potential to detect important molecular biomarkers of early cancer based on their unique spectral signatures. Several drawbacks have limited its use for in vivo screening applications: most notably the poor temporal and spatial resolution, high expense, and low optical throughput of existing hyperspectral imagers. We present the development of a new real-time hyperspectral endoscope (called the image mapping spectroscopy endoscope) based on an image mapping technique capable of addressing these challenges. The parallel high throughput nature of this technique enables the device to operate at frame rates of 5.2 frames per second while collecting a (x, y, λ) datacube of 350 × 350 × 48. We have successfully imaged tissue in vivo, resolving a vasculature pattern of the lower lip while simultaneously detecting oxy-hemoglobin.

Compact Image Slicing Spectrometer (ISS) for hyperspectral fluorescence microscopy

An image slicing spectrometer (ISS) for microscopy applications is presented. Its principle is based on the redirecting of image zones by specially organized thin mirrors within a custom fabricated component termed an image slicer. The demonstrated prototype can simultaneously acquire a 140 nm spectral range within its 2D field of view from a single image. The spectral resolution of the system is 5.6 nm. The FOV and spatial resolution of the ISS depend on the selected microscope objective and for the results presented is 45 x 45 microm(2) and 0.45 microm respectively. This proof-of-concept system can be easily improved in the future for higher (both spectral and spatial) resolution imaging. The system requires no scanning and minimal post data processing. In addition, the reflective nature of the image slicer and use of prisms for spectral dispersion make the system light efficient. Both of the above features are highly valuable for real time fluorescent-spectral imaging in biological and diagnostic applications.

Virus-induced gene silencing and its application in characterizing genes involved in water-deficit-stress tolerance

Understanding post-transcriptional gene silencing (PTGS) phenomena in plants has provided breakthroughs in advancing plant functional genomics. A recently developed approach based on one of the strategies adopted by plants to defend against viruses, called virus-induced gene silencing (VIGS), is being widely used to enumerate the function of plant genes. Since its discovery, VIGS has been widely used to characterize plant genes involved in metabolic pathways, homeostasis, basic cellular functions, plant-microbe, plant-nematode and plant-herbivore interaction. Recently, the application of this technique has been extended to characterize the genes and cellular processes involved in abiotic-stress tolerance, and in particular drought and oxidative stress. Because abiotic-stress tolerance is multigenic, identification and characterization of genes involved in this process is challenging. VIGS could become one among the several potential tools in understanding the relevance of these stress-responsive genes. Development of VIGS protocols for the use of heterologous gene sequences as VIGS-inducers has extended its applicability to analyze genes of VIGS recalcitrant plant species. This article describes the methodology of VIGS for characterizing the water-deficit-stress-responsive genes, precautions to be taken during the experimentation, and future application of this technology as a fast forwarded as well as a reverse genetics tool to identify and characterize plant genes involved in drought tolerance. We also describe the importance of accurate water-deficit-stress imposition and quantification of stress-induced changes in the silenced plants during the process of screening to identify genes responsible for tolerance. Further, limitations of VIGS in characterizing the abiotic-stress-responsive genes are noted, with suggestions to overcome these limitations.

Highly sensitive restriction enzyme assay and analysis: a review

Biological assays at the single molecule level are crucial to fundamental studies of DNA-protein mechanisms. In order to cater for high throughput applications, one area of immense research potential is single-molecule bioassays where miniaturized devices are developed to perform rapid and effective biological reactions and analyses. With the success of various emerging technologies for engineering miniaturized structures down to the nanoscale level, supported by specialized equipment for detection, many investigations in the field of life science that were once thought impossible can now be actively explored. In this review, the significance of downscaling to the single-molecule level is firstly presented in selected examples, with the focus placed on restriction enzyme assays. To determine the effectiveness of single-molecule restriction enzyme reactions, simple and direct analytical methods based on DNA stretching have often been reliably employed. DNA stretching can be realized based on a number of working principles related to the physical forces exerted on the DNA samples. We then discuss two examples of a nanochannel system and a microchamber system where single-molecule restriction enzyme digestion and DNA stretching have been integrated, which possess prospective capabilities of developing into highly sensitive and high-throughput restriction enzyme assays. Finally, we take a brief look at the general trends in technological development in this field by comparing the advantages and disadvantages of performing assays at bulk, microscale and single-molecule levels.

A line-scanning semi-confocal multi-photon fluorescence microscope with a simultaneous broadband spectral acquisition and its application to the study of the thylakoid membrane of a cyanobacterium Anabaena PCC7120

We describe the construction and characterization of a laser-line-scanning microscope capable of detection of broad fluorescence spectra with a resolution of 1 nm. A near-infrared femtosecond pulse train at 800 nm was illuminated on a line (one lateral axis, denoted as X axis) in a specimen by a resonant scanning mirror oscillating at 7.9 kHz, and total multi-photon-induced fluorescence from the linear region was focused on the slit of an imaging polychromator. An electron-multiplying CCD camera was used to resolve fluorescence of different colours at different horizontal pixels and fluorescence of different spatial positions in a specimen at different vertical pixels. Scanning on the other two axes (Y and Z) was achieved by a closed-loop controlled sample scanning stage and a piezo-driven objective actuator. The full widths at half maximum of the point-spread function of the system were estimated to be 0.39-0.40, 0.33 and 0.56-0.59 mum for the X (lateral axis along the line-scan), Y (the other lateral axis) and Z axes (the axial direction), respectively, at fluorescence wavelengths between 644 and 690 nm. A biological application of this microscope was demonstrated in a study of the sub-cellular fluorescence spectra of thylakoid membranes in a cyanobacterium, Anabaena PCC7120. It was found that the fluorescence intensity ratio between chlorophyll molecules mainly of photosystem II and phycobilin molecules of phycobilisome (chlorophyll/phycobilin), in the thylakoid membranes, became lower as one probed deeper inside the cells. This was attributable not to position dependence of re-absorption or scattering effects, but to an intrinsic change in the local physiological state of the thylakoid membrane, with the help of a transmission spectral measurement of sub-cellular domains. The efficiency of the new line-scanning spectromicroscope was estimated in comparison with our own point-by-point scanning spectromicroscope. Under typical conditions of observing cyanobacterial cells, the total exposure time became shorter by about 50 times for a constant excitation density. The improvement factor was proportional to the length of the line-scanned region, as expected.

High throughput easy microinjection with a single-cell manipulation supporting robot

A single-cell manipulation supporting robot (SMSR) has been developed for the high throughput and easy microinjection. Its concept is to let an experimenter concentrate his/her attention only on the microinjection by facilitating other associated works. SMSR was applied to the microinjection into rice protoplasts and mouse embryonic stem (ES) cells. The microinjection into these cells is exceptionally difficult than usual animal cells such as fibroblasts. In the case of rice protoplast, for example, non-stop microinjection into 100 cells could be done within 1h that was 17-times faster than that of the robot-less work. The success rate was 7-8% that was same level obtained by the robot-less work. The present results indicate that SMSR is a useful machine for the microinjection of specific genes and proteins in living cells to analyze their respective functions, which is an urgent and important subject in the post-genome era.

Simultaneous imaging of multiple fluorescent probes in bio-cells

In order to obtain the full spectrum from 400 to 800 nm of each pixel of a microscopic image, a unique spectro-imaging system was developed using an image slicer. The image slicer is composed of 100 photo fibers which are arranged in a matrix of 10 x 10 at the entrance and 100 x 1 at the exit. A line of this 100 signals is passed through a glism and projected onto a CCD. This system was applied to the fluorescent imaging of bio-cells. One of the demonstrative examples was simultaneous measurements of the Ca2+ concentration and the pH using of respective fluorescent probes. An electric signal was applied to BY-2 protoplasts and the fluorescent spectrum from 500 nm to 800 nm was measured every 5 s. The spectrum of the BY-2 protoplasts changed in response to the electric signal and the Ca2+ concentration, and the pH changes could be monitored. The wavelength resolution was satisfactory, but the space resolution was still rough in comparison with the usual microscopic systems. Notwithstanding these conditions, we could obtain discrete data from more than several tens of sites in a single-cell or a chain of several cells.

Multispectral imaging fluorescence microscopy for living cells

Multispectral imaging technologies have been widely used in fields of astronomy and remote sensing. Interdisciplinary approaches developed in, for example, the National Aeronautics and Space Administration (NASA, USA), the Jet Propulsion Laboratory (JPL, USA), or the Communications Research Laboratory (CRL, Japan) have extended the application areas of these technologies from planetary systems to cellular systems. Here we overview multispectral imaging systems that have been devised for microscope applications. We introduce these systems with particular interest in live cell imaging. Finally we demonstrate examples of spectral imaging of living cells using commercially available systems with no need for user engineering.