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Identification of Porphyrin-Silica Composite Nanoparticles using Atmospheric Solids Analysis Probe Mass Spectrometry

MRS Advances

Karler, Casey; Parchert, Kylea J.; Ricken, James B.; Carson, Bryan C.; Mowry, Curtis D.; Fan, Hongyou F.; Ye, Dongmei Y.

Porphyrins are vital pigments involved in biological energy transduction processes. Their abilities to absorb light, then convert it to energy, have raised the interest of using porphyrin nanoparticles as photosensitizers in photodynamic therapy. A recent study showed that self- assembled porphyrin-silica composite nanoparticles can selectively destroy tumor cells, but detection of the cellular uptake of porphyrin-silica composite nanoparticles was limited to imaging microscopy. Here we developed a novel method to rapidly identify porphyrin-silica composite nanoparticles using Atmospheric Solids Analysis Probe-Mass Spectrometry (ASAP-MS). ASAP-MS can directly analyze complex mixtures without the need for sample preparation. Porphyrin-silica composite nanoparticles were vaporized using heated nitrogen desolvation gas, and their thermo-profiles were examined to identify distinct mass- to-charge (M/Z) signatures. HeLa cells were incubated in growth media containing the nanoparticles, and after sufficient washing to remove residual nanoparticles, the cell suspension was loaded onto the end of ASAP glass capillary probe. Upon heating, HeLa cells were degraded and porphyrin-silica composite nanoparticles were released. Vaporized nanoparticles were ionized and detected by MS. The cellular uptake of porphyrin-silica composite nanoparticles was identified using this ASAP-MS method.

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TYPE Journal Article YEAR 2019
ScopusOSTIDOI

Posters for AA/CE Reception

Kuether, Robert J.; Allensworth, Brooke M.; Backer, Adam B.; Chen, Elton Y.; Dingreville, Remi P.; Forrest, Eric C.; Knepper, Robert; Tappan, Alexander S.; Marquez, Michael P.; Vasiliauskas, Jonathan G.; Rupper, Stephen G.; Grant, Michael J.; Atencio, Lauren C.; Hipple, Tyler J.; Maes, Danae M.; Timlin, Jerilyn A.; Ma, Tian J.; Garcia, Rudy J.; Danford, Forest L.; Patrizi, Laura P.; Galasso, Jennifer G.; Draelos, Timothy J.; Gunda, Thushara G.; Venezuela, Otoniel V.; Brooks, Wesley A.; Anthony, Stephen M.; Carson, Bryan C.; Reeves, Michael J.; Roach, Matthew R.; Maines, Erin M.; Lavin, Judith M.; Whetten, Shaun R.; Swiler, Laura P.

Abstract not provided.

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TYPE Presentation YEAR 2018
OSTI

Method for measuring the unbinding energy of strongly-bound membrane-associated proteins

Biochimica et Biophysica Acta - Biomembranes

La Bauve, Elisa; Vernon, Briana C.; Ye, Dongmei Y.; Rogers, David M.; Siegrist, Cathryn M.; Carson, Bryan C.; Rempe, Susan R.; Zheng, Aihua; Kielian, Margaret; Shreve, Andrew P.; Kent, Michael S.

We describe a new method to measure the activation energy for unbinding (enthalpy ΔH*u and free energy ΔG*u) of a strongly-bound membrane-associated protein from a lipid membrane. It is based on measuring the rate of release of a liposome-bound protein during centrifugation on a sucrose gradient as a function of time and temperature. The method is used to determine ΔH*u and ΔG*u for the soluble dengue virus envelope protein (sE) strongly bound to 80:20 POPC:POPG liposomes at pH 5.5. ΔH*u is determined from the Arrhenius equation whereas ΔG*u is determined by fitting the data to a model based on mean first passage time for escape from a potential well. The binding free energy ΔGb of sE was also measured at the same pH for the initial, predominantly reversible, phase of binding to a 70:30 PC:PG lipid bilayer. The unbinding free energy (20 ± 3 kcal/mol, 20% PG) was found to be roughly three times the binding energy per monomer, (7.8 ± 0.3 kcal/mol for 30% PG, or est. 7.0 kcal/mol for 20% PG). This is consistent with data showing that free sE is a monomer at pH 5.5, but assembles into trimers after associating with membranes. This new method to determine unbinding energies should be useful to understand better the complex interactions of integral monotopic proteins and strongly-bound peripheral membrane proteins with lipid membranes.

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TYPE Journal Article YEAR 2016
ScopusOSTIDOI

New Method for Measuring the Anchoring Energy of Strongly-Bound Membrane-Associated Proteins [Method for measuring the anchoring energy of strongly-bound membrane-associated proteins]

Biophysical Journal

Kent, Michael S.; La Bauve, Elisa L.; Vernon, Briana C.; Ye, Dongmei Y.; Rogers, David M.; Mayes, Cathryn M.; Carson, Bryan C.; Rempe, Susan R.; Zheng, Aihua Z.; Kielian, Margaret K.; Shreve, Andrew S.; Kent, Michael S.

Here, we describe a new method to measure the activation energy required to remove a strongly-bound membrane-associated protein from a lipid membrane (anchoring energy). It is based on measuring the rate of release of a liposome-bound protein during centrifugation on a sucrose gradient as a function of time and temperature. The method was used to determine anchoring energy for the soluble dengue virus envelope protein (sE) strongly bound to 80:20 POPC:POPG liposomes at pH 5.5. We also measured the binding energy of sE at the same pH for the initial, predominantly reversible, phase of binding to a 70:30 PC:PG lipid bilayer. The anchoring energy (37 +/- 1.7 kcal/mol, 20% PG) was found to be much larger than the binding energy (7.8 +/- 0.3 kcal/mol for 30% PG, or est. 7.0 kcal/mol for 20% PG). This is consistent with data showing that free sE is a monomer at pH 5.5, but assembles into trimers after associating with membranes. But, trimerization alone is insufficient to account for the observed difference in energies, and we conclude that some energy dissipation occurs during the release process. This new method to determine anchoring energy should be useful to understand the complex interactions of integral monotopic proteins and strongly-bound peripheral membrane proteins with lipid membranes.

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TYPE Journal Article YEAR 2016
OSTIDOI

Laser Machined Plastic Laminates: Towards Portable Diagnostic Devices for Use in Low Resource Environments

Electroanalysis

Harper, Jason C.; Carson, Bryan C.; Bachand, George B.; Arndt, William A.; Finley, Melissa F.; Brinker, C.J.; Edwards, Thayne L.

Despite significant progress in development of bioanalytical devices cost, complexity, access to reagents and lack of infrastructure have prevented use of these technologies in resource-limited regions. To provide a sustainable tool in the global effort to combat infectious diseases the diagnostic device must be low cost, simple to operate and read, robust, and have sensitivity and specificity comparable to laboratory analysis. In this mini-review we describe recent work using laser machined plastic laminates to produce diagnostic devices that are capable of a wide variety of bioanalytical measurements and show great promise towards future use in low-resource environments.

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TYPE Journal Article YEAR 2015
ScopusOSTIDOI

Characterization of differential toll-like receptor responses below the optical diffraction limit

Small

Aaron, Jesse S.; Carson, Bryan C.; Timlin, Jerilyn A.

Many membrane receptors are recruited to specific cell surface domains to form nanoscale clusters upon ligand activation. This step appears to be necessary to initiate cell signaling, including pathways in innate immune system activation. However, virulent pathogens such as Yersinia pestis (the causative agent of plague) are known to evade innate immune detection, in contrast to similar microbes (such as Escherichia coli) that elicit a robust response. This disparity has been partly attributed to the structure of lipopolysaccharides (LPS) on the bacterial cell wall, which are recognized by the innate immune receptor TLR4. It is hypothesized that nanoscale differences exist between the spatial clustering of TLR4 upon binding of LPS derived from Y. pestis and E. coli. Although optical imaging can provide exquisite details of the spatial organization of biomolecules, there is a mismatch between the scale at which receptor clustering occurs (<300 nm) and the optical diffraction limit (>400 nm). The last decade has seen the emergence of super-resolution imaging methods that effectively break the optical diffraction barrier to yield truly nanoscale information in intact biological samples. This study reports the first visualizations of TLR4 distributions on intact cells at image resolutions of <30 nm using a novel, dual-color stochastic optical reconstruction microscopy (STORM) technique. This methodology permits distinction between receptors containing bound LPS from those without at the nanoscale. Importantly, it is also shown that LPS derived from immunostimulatory bacteria result in significantly higher LPS-TLR4 cluster sizes and a nearly twofold greater ligand/receptor colocalization as compared to immunoevading LPS. A dual-color stochastic optical reconstruction microscopy technique is employed to gain insight into the nanoscale organization of the innate immune system receptor TLR4. Data indicate significant changes in TLR4 clustering behavior within the cell membrane in response to immunostimulatory and immunoevading bacterial antigens, thereby shedding light on virulence mechanisms of highly pathogenic microbes such as Yersinia pestis. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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TYPE Journal Article YEAR 2012
ScopusOSTIDOI

Characterization of Pathogens in Clinical Specimens via Suppression of Host Background for Efficient Second Generation Sequencing Analyses

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

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TYPE Conference YEAR 2012
OSTI

Copy of Automated Molecular Biology Platform Enabling Rapid & Efficient SGS Analysis of Pathogens in Clinical Samples

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

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TYPE Presentation YEAR 2012
OSTI

Automated Molecular Biology Platform Enabling Rapid & Efficient SGS Analysis of Pathogens in Clinical Samples

Branda, Steven B.; Jebrail, Mais J.; Van De Vreugde, James L.; Langevin, Stanley A.; Bent, Zachary B.; Curtis, Deanna J.; Lane, Pamela L.; Carson, Bryan C.; La Bauve, Elisa L.; Patel, Kamlesh P.; Ricken, James B.; Schoeniger, Joseph S.; Solberg, Owen D.; Williams, Kelly P.; Misra, Milind; Powell, Amy J.; Pattengale, Nicholas D.; May, Elebeoba E.; Lane, Todd L.; Lindner, Duane L.; Young, Malin M.; VanderNoot, Victoria A.; Thaitrong, Numrin T.; Bartsch, Michael B.; Renzi, Ronald F.; Tran-Gyamfi, Mary B.; Meagher, Robert M.

Abstract not provided.

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TYPE Conference YEAR 2012
OSTI

Super-resolution microscopy reveals protein spatial reorganization in early innate immune responses

Carson, Bryan C.; Timlin, Jerilyn A.

Over the past decade optical approaches were introduced that effectively break the diffraction barrier. Of particular note were introductions of Stimulated Emission/Depletion (STED) microscopy, Photo-Activated Localization Microscopy (PALM), and the closely related Stochastic Optical Reconstruction Microscopy (STORM). STORM represents an attractive method for researchers, as it does not require highly specialized optical setups, can be implemented using commercially available dyes, and is more easily amenable to multicolor imaging. We implemented a simultaneous dual-color, direct-STORM imaging system through the use of an objective-based TIRF microscope and filter-based image splitter. This system allows for excitation and detection of two fluorophors simultaneously, via projection of each fluorophor's signal onto separate regions of a detector. We imaged the sub-resolution organization of the TLR4 receptor, a key mediator of innate immune response, after challenge with lipopolysaccharide (LPS), a bacteria-specific antigen. While distinct forms of LPS have evolved among various bacteria, only some LPS variations (such as that derived from E. coli) typically result in significant cellular immune response. Others (such as from the plague bacteria Y. pestis) do not, despite affinity to TLR4. We will show that challenge with LPS antigens produces a statistically significant increase in TLR4 receptor clusters on the cell membrane, presumably due to recruitment of receptors to lipid rafts. These changes, however, are only detectable below the diffraction limit and are not evident using conventional imaging methods. Furthermore, we will compare the spatiotemporal behavior of TLR4 receptors in response to different LPS chemotypes in order to elucidate possible routes by which pathogens such as Y. pestis are able to circumvent the innate immune system. Finally, we will exploit the dual-color STORM capabilities to simultaneously image LPS and TLR4 receptors in the cellular membrane at resolutions at or below 40nm.

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TYPE Conference YEAR 2010
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A microfluidic platform for the fluidic isolation and observation of cells challenged with pathogens

Technical Digest - Solid-State Sensors, Actuators, and Microsystems Workshop

James, Conrad D.; Moorman, M.W.; Carson, Bryan C.; Joo, J.; Branda, C.S.; Manginell, Ronald P.; Lantz, J.; Renzi, R.; Martino, Anthony M.; Singh, Anup K.

Single-cell analysis offers a promising method of studying cellular functions including investigation of mechanisms of host-pathogen interaction. We are developing a microfluidic platform that integrates single-cell capture along with an optimized interface for high-resolution fluorescence microscopy. The goal is to monitor, using fluorescent reporter constructs and labeled antibodies, the early events in signal transduction in innate immunity pathways of macrophages and other immune cells. The work presented discusses the development of the single-cell capture device, the iCellator chip, that isolates, captures, and exposes cells to pathogenic insults. We have successfully monitored the translocation of NF-κB, a transcription factor, from the cytoplasm to the nucleus after lipopolysaccharide (LPS) stimulation of RAW264.7 macrophages.

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TYPE Conference YEAR 2010
ScopusOSTI

Resolving dynamics of cell signaling via real-time imaging of the immunological synapse

Timlin, Jerilyn A.; Burns, A.R.; Aaron, Jesse S.; Carson, Bryan C.; Stevens, Mark J.

This highly interdisciplinary team has developed dual-color, total internal reflection microscopy (TIRF-M) methods that enable us to optically detect and track in real time protein migration and clustering at membrane interfaces. By coupling TIRF-M with advanced analysis techniques (image correlation spectroscopy, single particle tracking) we have captured subtle changes in membrane organization that characterize immune responses. We have used this approach to elucidate the initial stages of cell activation in the IgE signaling network of mast cells and the Toll-like receptor (TLR-4) response in macrophages stimulated by bacteria. To help interpret these measurements, we have undertaken a computational modeling effort to connect the protein motion and lipid interactions. This work provides a deeper understanding of the initial stages of cellular response to external agents, including dynamics of interaction of key components in the signaling network at the 'immunological synapse,' the contact region of the cell and its adversary.

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TYPE SAND Report YEAR 2009
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65 Results
65 Results