Optical imaging techniques

Annexin V-functionalized crosslinked iron oxide (CLIO) was designed as a contrast agent for MRI, which was additionally labeled with Cy5.5 to allow colocalization with optical imaging techniques [98]. Alternatively, conjugation of multiple Gd-DTPA molecules or SPIO particles to the C2 domain of synaptotagmin I was shown to allow the detection of apoptotic cells in vitro [99]. Zhao et al. [100] were the first to apply a C2 domain-functionalized SPIO and showed very promising results for future in vivo applications of MR contrast agents for the detection of apoptotic sites. 

One optical imaging technique that circumvents the problem of multiple fight scattering is to estimate the bubble size distribution from the area individual foam bubbles occupy ai a glass surface. Such experiments, and the systematic differences between bulk and surface bubble distributions, have been reviewed. Another technique that also directly measures the bubble size distribution is ihe use Of a Coulter counter, where individual bubbles are drawn through a small lube and counted. This yields a direct measure of the bubble size distribution, hut it is invasive and cannot probe the structure of the foam. 

SECM instruments (77,78) will undoubtedly increase the scope and power of SECM. Further improvements in the power and scope of SECM has resulted from its coupling scanning probe or optical imaging techniques, such as AFM (57,79) or single-molecule fluorescence spectroscopy (80). The combined SECM-AFM technique offers simultaneous topographic and electrochemical imaging in connection to a probe containing a force sensor and an electrode component, respectively. 

Spatial odor images for these compounds in the dorsal part of rat OB are shown in Figure 6.4. These odor maps were obtained using optical imaging techniques involving... 

For expansion measurements in a pulse calorimeter, two other groups of measurement techniques have been developed interferometric techniques and optical imaging techniques. Different interferometers have been developed by INRiM in Italy to measure the longitudinal expansion of a sample with a laser interferometer [49, 50] and by NIST in USA to record thermal expansion using a modified Double-Michelson-Interferometer [51]. A expansion measurement setup using a similar device to NIST was recently built at the Austrian Foundry... 

Nevertheless, NMR imaging suffers from poor lateral resolution ( 10 un) and confocal microscopy is limited by poor penetration depth ( 80 pm) and vertical resolution especially in the case of opaque samples [20]. Optical coherence microscopy/optical coherence tomography (OCT) is more advantageous than the earlier-mentioned two optical imaging techniques and is being widely used in characterization... 

The earliest non-invasive imaging method for islet grafts is the optical imaging technique based on bioluminescence for visualization of transplanted islets [15]. This bioluminescence imaging (BLI) system utilizes the reaction between luciferase enzymes and luciferin substrates. The luciferase enzyme generates visible light by the oxidation of substrate in the presence of oxygen. The... 

Stroke. As a neurologic deficit of cerebrovascular cause, strokes account for the second most frequent cause of death after coronary artery disease, and are the leading cause of permanent physical and mental disability [109] (Figure 5). Non-invasive optical imaging techniques can prove to be an important asset as a diagnostic and monitoring tool with animal stroke models. LSCI has been used to... 

Chong, K., et al. Current Optical Imaging Techniques for Brain Tumor Research Application of in vivo Laser Scanning Microscopy Imaging with a Cranial Window System, pp. 155-172. InTech, Rijeka (2011)... 

Optical imaging is often used to characterize exoelectrogen on the anode, including the morphology and thickness of biofilm. Two types of optical imaging techniques are popularly used scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM). 

The Feret diameter, fi p, is a statistical diameter representing the mean value of the distances between pairs of parallel tangents to a projected outline of the particle, as shown in Fig. 1. The Feret diameter is usually used in particle characterization employing the optical imaging technique to be discussed later. 

OCT is an optical imaging technique that has been coupled successfully with endoscopy to allow scanning inside the body at depths of typically a few millimeters [31,32]. OCT is a high-resolution, non-destructive optical technique used for cross-sectional imaging of biological tissue [33]. Most conventional endoscopic OCT probes use lenses with fixed focal lengths as the focusing objectives. 

Apoptosis. Binding of annexin V or the C2A domain of synaptotagmin I to phosphatidylserine expressed on the surface of apoptotic cells can, when labeled with appropriate probe molecules, be used to detect the presence of apoptosis using radionuclide, magnetic resonance, and optical imaging techniques. The preparation of a biotinylated C2A-GST fusion protein was described, and its capability, when used in conjunction with fiuorescein-labeled streptavidin, of detecting apoptotic cells by flow cytometry was compared directly with the performance of a preparation of fluorescein-labeled annexin... 

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