Jacobson Research Group

Description of the video:

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Research activities in the Jacobson group range from instrumentation development in fundamental
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studies of micro- and nano- fluidics, charge transport, and opti-fluidics, to biological assays
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including virus assembly, bacterial development, cancer diagnostics, and phylogenetic toxicology.
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Group members will now give a brief overview of their projects.
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Hi, my name is Mike, I'm a fifth-year graduate student in Dr Jacobson's lab and I
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work on the nanofluidic project. What I look at is the detection of HPV capsid,
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and our main technique is resistive-pulse sensing. How it works is we have a capsid
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that will get electrophoretically driven through this electrically-biased pore.
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Here we have the capsid is not in the pores and we get a baseline current of approximately 17
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nanoamps. As the particle is driven into the pore we get a displacement of electrolyte,
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which causes an increase in resistance so it decreases the current amplitude. From the
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difference from this baseline to the trough here we can get a sense of how large that particle is.
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We have three pulses so that we can have improved signal averaging from three pores, and here you
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can see we can hundreds of particles in a matter of minutes, each of which is measured three times.
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Hi everybody, my name is Mi, and this is the instrument we use to make our nanofluidic device.
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Here in the middle column is the one we use to make scanning electron microscopy to help us
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find our samples. Back here we have the thing which can spot the materials of our surface
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to make the features that we design. We can also do depositions with this gas injection system.
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With that we are able to make various nanostructures.
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Hello, I'm Tanner, and I'm a second-year analytical student.
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Hi, I'm Lizzie, and I'm a first-year analytical student. We both
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are on the nanofluidics project with an emphasis on extracellular vesicles.
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Extracellular vesicles range anywhere from 30 nanometers to a few microns in diameter.
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It is important to study EVs because they have been shown to resemble the mother cell from
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which they come from. They've also been linked to cell-to-cell communication and they can be
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used as biomarkers to identify diseases. We also utilize resistive-pulse sensing where we use this
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technique to characterize single particles for their size and charge.
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I work on the separations project. Here you can see that we use the focused ion
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beam in order to mill a device to perform these separations of polystyrene beads.
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Here is a live video of the separation occurring. This will later be adapted to research EVs.
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Hello, my name is Namyoon Lee in Professor Jacobson's group, and I'm a first-year student on
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the glycan project. The goal of my project is to identify potential cancer glycan biomarkers from
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body fluids. I use samples such as human exosomes, human urine, and human serum to get glycans. For
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my project to analyze data I use CE-MS, capillary electrophoresis mass spec. Here is the brief data
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of the glycan profile obtained from Dr Woran Song (alumna of the group). The key
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points of this technique is we can separate the isomers of the glycan profile like these two.
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Hello, I'm Ziyu, a fourth-year grad student in Jacobson's lab. This is the detection instrument
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for our glycans. It's called the Orbitrap Fusion Lumos, a very advanced instrument
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made by Fisher Science. With this instrument we can detect very small molecules
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with very high resolution. It helps us to achieve what we want
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for cancer screening and also for our phylotox project. The phylotox project will focus on small
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molecules including lipids, sugars, and amino acids. I will talk about that in the next chapter.
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In the phylotox project our goal is to profile the metabolome of model organisms
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and also examine the metabolomic changes under regulatory exposure,
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which are the small molecules I mentioned previously. In this slide you can see this
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is a phylogenetic tree. Our target model organisms will include C. elegans, fruit flies, zebrafish,
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xenopus, and probably in the future we will also use human cell lines for our future project.
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The techniques we use here will be electron spray ionization direct infusion mass spec.
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Hi, I'm Gerardo. I'm a first-year student and I work with Ziyu in the
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tandem mass spectrometry focus of the phylotox project. We use the Triversa
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Nanomate and the Orbitrap Fusion Lumos for automated direct infusion mass spectrometry.
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The Nanomate acts as an autosampler and an ion source by using this electrospray chip.
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By using direct infusion instead of chromatography we're able to run our experiments in a matter of
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seconds instead of hours. It's worth noting that the Fusion Lumos and the Nanomate were
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not designed to work together, so the machine shop, the electronics shop, and the laboratory
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for biological mass spectrometry facility here at IU all worked together to create this setup.
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Hi,
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I'm Brigham Pope. I'm a second-year graduate student in the Jacobson group. I'm in the
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photolithographic mapping project. After we mill nano apertures, we illuminate them with UV light
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to get a 3D model of how the light passes through. We use a negative tone photoresist that lets us
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see where the UV light has passed through these apertures. By seeing these three-dimensional
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models we can determine what uses we can use these apertures for in microfluidic devices.
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Hi, I'm Laura and I'm a second-year graduate student here in the Jacobson lab.
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I work in the bacteria project where we use this microfluidic device to trap and image bacteria.
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Our device works with vacuum pressure to control the different valves and to control the flow,
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as well as the bacteria growth in the channels and the delivery of the media.
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We here have our microscope in which we use fluorescence to track the different bacteria.
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Over here in our video you can see how across time we are able to see how the
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bacteria grow in our channels and track different products inside the bacteria.