<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ks_c_5601-1987">
<style type="text/css" style="display:none;"> P {margin-top:0;margin-bottom:0;} </style>
</head>
<body dir="ltr">
<div style="font-family: Calibri, Arial, Helvetica, sans-serif; font-size: 12pt; color: rgb(0, 0, 0);" class="elementToProof">
<table align="center" width="600" style="font-family:Arial, sans-serif;font-size:medium">
<tbody>
<tr>
<td><img alt="Dissertation Defense Announcement at the Cullen College of Engineering" width="600" height="171" src="https://www.egr.uh.edu/sites/www.egr.uh.edu/files/enews/2022/images/dissertation1.png">
<table align="center">
<tbody>
<tr>
<td align="center" style="padding:40px 20px 10px">
<div style="font-size:24px;color:rgb(200, 16, 46);line-height:28px"><strong>Advances in Plasmonic Biosensing Towards Detection, Quantitative Analysis and Molecular
<br>
</strong></div>
<div style="margin-top:5px;line-height:22px"><br>
</div>
<div style="margin:30px 0px;line-height:20px">
<div style="font-size:18px;margin-bottom:5px"><strong>Nareg Ohannesian</strong></div>
<div style="font-size:14px">
<div style="font-family:Arial, Helvetica, sans-serif;line-height:22px;margin:0px 0px 5px">
6-29-2022; 10:00 am - 12:00 pm (CST)<br>
<br>
Zoom: <a href="https://urldefense.com/v3/__https://uh-edu-cougarnet.zoom.us/j/97514918252?pwd=Q3JZTFQ5T0wwSFV3WEVuYXluMXhTUT09*success__;Iw!!LkSTlj0I!GbhqBAbAAxSG3XLK8cx7n0EwCBZ-VolumeXkGqLsIKGIpepRlCPvXPCk4M82wsb5AGIkTmf4ZnN2loi0ptAr33oUEaE$" id="LPNoLPOWALinkPreview">
https://uh-edu-cougarnet.zoom.us/j/97514918252?pwd=Q3JZTFQ5T0wwSFV3WEVuYXluMXhTUT09#success</a>
<div class="_Entity _EType_OWALinkPreview _EId_OWALinkPreview _EReadonly_1"></div>
<span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;text-align:start;background-color:rgb(255, 255, 255);display:inline !important">Meeting ID: 975 1491 8252</span><br style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;text-align:start;background-color:rgb(255, 255, 255)">
<span style="font-family:Calibri, Arial, Helvetica, sans-serif;font-size:16px;text-align:start;background-color:rgb(255, 255, 255);display:inline !important">Passcode: 032873</span><br>
</div>
</div>
</div>
<div style="font-size:14px;line-height:20px">
<p style="font-family:Arial, Helvetica, sans-serif;line-height:22px;margin:0px 0px 5px">
<strong>Committee Chair:</strong><br>
Wei-Chuan Shih, Ph.D.<br>
</p>
</div>
<div style="font-size:14px;line-height:20px">
<p style="font-family:Arial, Helvetica, sans-serif;line-height:22px;margin:0px 0px 20px">
<strong>Committee Members:</strong><br>
John C. Wolfe, Ph.D. | Xiaonan Shan, Ph.D. | Karen Martirosyan, Ph.D. | Steven H. Lin, MD-Ph.D.</p>
</div>
</td>
</tr>
<tr>
<td style="padding:0px 20px 20px">
<p style="font-family:Arial, Helvetica, sans-serif;font-size:16px;line-height:22px;margin:15px 0px;color:rgb(200, 16, 46)">
<strong>Abstract</strong></p>
<p style="font-family:Arial, Helvetica, sans-serif;font-size:14px;line-height:22px;margin:15px 0px">
Exosomes are small (бн30 nm to бн250 nm in diameter), single phospholipid-membrane, extracellular vesicles secreted by all mammalian cells into the bloodstream. Exosomes share the same topology as the parent cell, including selective surface proteins, lipids,
and internally stored nucleic acids. Exosomes are responsible for intercellular communication through the transportation of genetic molecules (DNA, RNA, miRNA, etc.) and play a crucial role in human health from developing immunity to cancer. The transition
of a parent cell from healthy to cancerous results in the dysregulation of exosomal surface proteins and stored genetic molecules. In turn, profiling exosomal properties can provide an insight into the state of the parent cell undergoing physical/property
changes which include cancer progression. However, due to the nanoscale size of exosomes, currently available analytical tools suffer immense limitations such as detection due to insufficient light, low throughput/yield, and require extensive labeling for
molecular content. To address these limitations, we developed plasmonic platforms based on arrayed substrates fabricated by our group called nanoporous gold disk (NPGD) array and arrayed gold nanodisks on invisible (AGNIS). Fabricated NPGD and AGNIS possess
a remarkable plasmonic property called localized surface plasmon resonance (LSPR). LSPR describes the interaction of free electrons in the metal with electromagnetic waves and results in a strong absorption peak. Due to the highly tunable LSPR absorbance peak
of the NPGD array, plasmonic microbubbles of controlled size are generated upon irradiating near-infrared (NIR) light. Plasmonic microbubble can direct and concentrate dispersed micro-/nanoparticles in the liquid at any location on the NPGD surface. Redistributing
particles through plasmonic microbubbles facilitates profiling exosomes at concentrations below the dynamic range and the detection limit of the analytical system. Next, we used the AGNIS to develop an imaging technique called plasmonic nanoaperture label-free
imaging (PANORAMA) that detects dielectric nanoparticles based on unscattered light. This procedure could determine the size, number, and availability of nanoparticles past 25 nm and measure their distance from the plasmonic surface within a few milliseconds.
Combining PANORAMA with fluorescence microscopy allows label-free counting, sizing, and surface protein and cargo micro-RNA characterization at the single exosome level. Finally, using the PANORAMA-fluorescence imaging system, we identify healthy donor plasmas
from cancer patients by label-free detection of retained exosomes and MIR-21 occurrence among retained exosomes from plasma. </p>
</td>
</tr>
</tbody>
</table>
</td>
</tr>
<tr>
<td><img alt="Engineered For What's Next" width="600" height="82" src="https://www.egr.uh.edu/sites/www.egr.uh.edu/files/enews/2022/images/dissertation2.png"></td>
</tr>
</tbody>
</table>
<br>
</div>
</body>
</html>