A grant has been awarded to Dr. Ben-Amotz at Purdue University to develop a high speed chemical imaging instrument which will track molecules in living cells. Current chemical imaging instruments are limited by a trade-off between high throughput (speed) and high information content (resolution). This new Multivariate Hyperspectral Imaging (MHI) instrument will overcome these limitations by using a novel data compression strategy to produce a high speed "chemical vision" system. In other words, the MHI instrument will take pictures and movies that reveal where particular molecules are located and how they are moving. In addition to cell imaging, the MHI is expected to be useful for a wide variety of other biological, medical and environmental applications, as further described below.
The MHI instrument may be viewed as the first of a new breed of chemical imaging spectrometers which rapidly collects full-spectral images using multivariate data compression. This data compression strategy is related to commonly used music and video data compression methods. However, a key difference is that the MHI uses data compression to speed up the collection of hyperspectral images. This is achieved using a high resolution spatial light modulator (SLM) to rapidly detect full-spectral response functions. The resulting spectral-response intensities may be used either to directly image cells and cell components or to reconstruct complete high resolution spectral images. This hardware data compression strategy is expected to enhance spectral imaging speeds by a factor of 1000, thus facilitating high resolution chemical imaging and dynamics studies of individual live cells, as well as high-throughput/high-content cell screening, and other cell/tissue imaging applications.
The MHI instrument is expected to benefit biological and environmental disease/pathogen detection and identification, as well as the education of graduate and undergraduate students. Impacts include fast high-resolution (high-throughput/high-content) imaging of cells for early detection of environmental pathogens and bio-hazards and research leading to elucidation of the mechanisms by which biomolecules influence cellular and tissue function. In other words, the MHI could be used to rapidly read DNA and protein arrays as well as to monitor and map chemicals in environmental and engineering composites. Educational activities include both the specialized training of graduate students in advanced cell handling and imaging techniques, as well as the multi-disciplinary training which graduate and undergraduate students will receive in using MHI instrument for various biological/bio-engineering cell imaging research projects.
High Speed Chemical Sensing and Imaging using Digital Compressive Detection Imagine being able to look at an object and instantly visualize its entire chemical composition, or to track chemical changes faster than the eye can see. That is what compressive detection is all about. Doing it requires using some of the same strategies that are used to compress sound and image files in order to store data more compactly. But instead the aim of compressive detection is to make it possible to collect data in less time. The multivariate hyperspectral imaging system that we have created makes use of a spatial light modular, similar to that found inside computer projectors. We use either a anolog (liquid crystal) or digital (multimirror device) spatial light modulators to rapidly project chemical information. The key to the high speed of our instrument is a mathematical algorithm which maximizes the speed at which the light emitted by molecules can be used to chemically identify them. The instrument we have developed is somewhat like a color camera with hundreds of colors, which is sensitive and fast enough to positively distinguish chemical differences using fewer than 100 photons of light, measured in less than one thousanths of a second. The instrument that we have created can be viewed as the natural evolution of prism which separates light into different colors. Our instrument can do that, but it can also simultaneously detect different combinations of colors to produce a characteric optical fingerprint of a molecule. Those fingerprints make it possible to selectively see different chemical species. It is as if you could put on a pair of glasses that made averything in a a picture disappear except the object you are looking for. There are many things which such an instrument could be used to do, from helping surgeons locate cancer tumors, to spoting pathogens in our food or environment, to improving the formulation of pharmaceutical, or enhancing manufacturing efficiency.
