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Wyatt N. Vreeland, Abraham H. Abouzeid, Silvia Muro, Rasa Ghaffarian
Purpose: Multimeric targeting of drugs to intercellular adhesion molecule 1 (ICAM-1), a receptor expressed on various cell types and disease conditions, facilitates intracellular drug uptake via cell adhesion molecule (CAM) endocytosis. While uptake by
Alexander Tselev, Jeyavel Velmurugan, Andrei Kolmakov
The ability of the near-field microwave microscopy to image subsurface structures has been realized shortly after the invention of the technique. Based on these capabilities, we propose and successfully tested a novel concept of in situ near-field scanning
Sara Abrahamsson, Robert Ilic, Jan Wisniewski, Brian Mehl, Liya Yu, Lei Chen, Marcelo I. Davanco, Laura Oudjedi, Jean Bernard Fiche, Bassam Hajj, Xin Jin, Joan Pulupa, Christine Cho, Mustafa Mir, Mohamed El Beheiry, Xavier Darzacq, Marcelo Nollmann, Maxime Dahan, Carl Wu, Timothee Lionnett, James Alexander Liddle, Cornelia Bargmann
Multifocus microscopy (MFM) allows high-resolution instantaneous three-dimensional (3D) imaging and has been applied to study biological specimens ranging from single molecules inside cell nuclei to entire embryos. In any live microscopy application
Alexander Tselev, Jeyavel Velmurugan, Anton Ievlev, Sergei Kalinin, Andrei Kolmakov
Noninvasive in situ nanoscale imaging in liquid environments is a current imperative in analysis of delicate bio-medical objects and electrochemical processes at reactive liquid-solid interfaces. Microwaves of a few gigahertz frequency offer photons of
Christian D. Ahrberg, Robert Ilic, Andreas Manz, Pavel Neu?il
Here we report one of the smallest real-time PCR system up to date with approximate size of 100 mm × 60 mm × 33 mm. The system is an autonomous unit requiring an external 12 V power supply. Four simultaneous reactions are performed in form of virtual
Eugene Paulechka, Tsjerk A. Wassenaar, Kenneth Kroenlein, Andrei Kazakov, Alexander Smolyanitsky
We propose a water-immersed nucleobase-functionalized suspended graphene nanoribbon as an intrinsically selective device for nucleotide detection. The proposed sensing method combines Watson–Crick selective base pairing with graphene's capacity for
De-Hao D. Tsai, Yi-Fu Lu, Frank W. DelRio, Tae Joon Cho, Suvajyoti S. Guha, Michael R. Zachariah, Fan Zhang, Andrew J. Allen, Vincent A. Hackley
We report a comprehensive strategy based on implementation of orthogonal measurement techniques to provide critical and verifiable material characteristics for functionalized gold nanoparticles (AuNPs) used in biomedical applications. Thiolated
NIST recently has released a SiNP reference material RM8027 that consists of five hermetically sealed pre-scored glass ampoules, each containing nominally 1 ml of cyclohexane-stabilized SiNPs suspended in toluene. The suspension contains particles
Here we report a microfluidic system that enables rapid and efficient remote loading of amphipathic drugs into nanoscale liposomes, combining liposome synthesis and remote drug loading in a continuous integrated process. Unlike established bulk methods for
We experimentally demonstrate that the three-dimensional (3-D) shape variations of nanometer-scale objects can be resolved and measured with sub-nanometer scale sensitivity using conventional optical microscopes by analyzing 3-D optical data using the
Wyatt N. Vreeland, Renee R. Hood, Don L. DeVoe, Francisco J. Atencia, Donna M. Omiatek
A novel microscale device has been developed to enable the one-step continuous flow assembly of monodisperse nanoscale liposomes using three-dimensional microfluidic hydrodynamic focusing (3D-MHF) in a radially symmetric capillary array. The 3D-MHF flow
Navin C. Sabharwal, Victoria Savikhin, Joshua Turek-Herman, John M. Nicoludis, Veronika Szalai, Liliya Yatsunyk
Guanine quadruplexes (GQ) are four-stranded DNA structures formed by guanine-rich DNA sequences. Formation of GQs inhibits cancer cell survival, but detecting GQs in vivo has proved difficult, in part because of GQ structural diversity. Development of GQ
Wyatt N. Vreeland, Renee R. Hood, Eric Kendall, Don L. DeVoe, Julia Finkel, Mariana Junqueira, Zenaide Quezado
Microfluidic synthesis of small and nearly-monodisperse liposomes is used to investigate the size-dependent passive transdermal transport of nanoscale lipid vesicles. While large liposomes with diameters above 105 nm are found to be excluded from deeper
De-Hao D. Tsai, Tae Joon Cho, Frank W. DelRio, Justin Gorham, Jiwen Zheng, Jiaojie Tan, Michael R. Zachariah, Vincent A. Hackley
We report a systematic study of the controlled formation of discrete-size gold nanoparticle clusters (GNCs) by interaction with the reducing agent dithiothreitol (DTT). Asymmetric-flow field flow fractionation and electrospray differential mobility
Suzanne Ahmed, Wei Wang, Lamar O. Mair, Robert D. Fraleigh, Sixing Li, Luz A. Castro, Mauricio Hoyos, Tony J. Huang, Thomas E. Mallouk
The recent discovery of fuel-free propulsion of nanomotors using acoustic energy has provided a new avenue for using nanomotors in biocompatible media. Crucial to the application of nanomotors in biosensing and biomedical applications is the ability to
Wyatt N. Vreeland, Abhay U. Andar, Renee R. Hood, Don L. DeVoe, Peter W. Swaan
Purpose: This study investigates the cellular uptake and trafficking of liposomes in Caco-2 cells, using vesicles with distinct average diameters ranging from 40 nm-276 nm. Liposomes were prepared by microfluidic hydrodynamic flow focusing, producing
De-Hao D. Tsai, Tae Joon Cho, Sherrie R. Elzey, Julien C. Gigault, Vincent A. Hackley
We report a high-resolution and traceable method to quantify the drug loading on nanoparticle-based cancer therapeutics, and demonstrate this method using a model cisplatin functionalized dendron-gold nanoparticle (AuNP) conjugate. Electrospray
We have fabricated and characterized a novel DNA based nanofiber created by synergistic self-assembly of guanine quadruplex (Hoogsteen base pairing) and double-stranded DNA (Watson-Crick base pairing). The assembly of our nanofibers occurs in several steps
Robert F. Cook, Sang-Min Lee, De-Hao D. Tsai, Vincent A. Hackley, Martin W. Brechbiel
We demonstrate a prototype approach to formulate gold nanoparticle (AuNP)based Xray absorbing adjuvant agents through surfaceengineering of cisplatin pharmacophore (PtII) with lipoic acidmodified polyacrylate (denoted as PtIIAuNPs). Design of PtII
Molecular dynamics (MD) simulations were used to refine and extend a theoretical model that describes the interactions of single polyethylene glycol molecules (PEGs) with an α-hemolysin nanopore. A previously developed analytical model assumed that PEG
Nanoparticles have emerged as promising therapeutic and diagnostic tools, due to their unique physicochemical properties. The specific core and surface chemistries, as well as nanoparticle size,all play critical roles in particle transport and interaction
Joseph E. Reiner, Joseph W. Robertson, Daniel L. Burden, Lisa K. Burden, Arvind Balijepalli, John J. Kasianowicz
The ability to perturb large ensembles of molecules from equilibrium led to major advances in understanding reaction mechanisms in chemistry and biology. Here, we demonstrate the ability to control, measure, and make use of rapid temperature changes of