Hongyou Fan, Sandia National Laboratories
Feng Bai, Henan University
Mei Cai, General Motors Company
Yu Han, King Abdullah University of Science and Technology
NM05.01: Session I
Monday AM, April 02, 2018
PCC North, 200 Level, Room 229 B
8:00 AM - NM05.01.01
Aminolated and Thiolated PEG-Covered Gold Nanostructures with High Stability and Anti-Aggregation for Lateral Flow Devices
Purdue University1Show Abstract
The few lateral flow assays (LFAs) established for detecting the endocrine disrupting chemical (EDC) bisphenol A (BPA) have employed citrate-stabilized gold nanoparticles (GNPs), which have inevitable limitations and instability issues. To address these limitations, we developed more stable sensitive lateral flow assay by designing strategies for modifying the surfaces of gold nanostructures with polyethylene glycol and then testing their effectiveness and sensitivity toward BPA in an LFA.
To further enhance detection, the work was extended to the incorporation of gold nannostructures into the design of a surface-enhanced Raman scattering lateral flow assay (SERS-LFA). The assay includes high-SERS-performance gold nanoparticles, i.e., 40 nm gold nanostars (GNSs), and 4-aminothiolphenol (4-ATP) as a Raman reporter. To demonstrate the performance of this SERS-LFA kit toward BPA detection, we tested BPA stock solutions with concentrations ranging from 0 to 32 ppb. Without the application of any enhancement strategy, this modified BPA LFA can achieve a naked-eye limit of detection (LOD) of 0.8 ng/mL, which is 12.5 times better than the LOD of other reported BPA LFAs, and a quantitative LOD of 0.472 ng/mL. The limit of detection for the SERS signals was 0.074, which was 202 and 8 times more sensitive than those of visual intensity and color intensity quantification, respectively. The range of quantification of the SERS signals doubled compared to that of color intensity quantification.
8:30 AM - NM05.01.02
Colloidal Nanoparticles for Ultrasensitive Biosensing
Imperial College London1Show Abstract
This talk will provide an overview of our recent developments in the design of nanomaterials for ultrasensitive biosensing. Bio-responsive nanomaterials are of growing importance with potential applications including drug delivery, diagnostics and tissue engineering (1). Using enzyme-mediated signal readouts we have developed a suite of nanoparticle based ultrasensitive biosensing approaches as well as a cell/tissue-interfacing nanoneedle platform (2). We are applying these biosensing approaches both in high throughput drug screening and to diagnose diseases ranging from cancer to global health applications.
 Stevens MM, George JH, Exploring and engineering the cell surface interface., Science, 2005, Vol:310, Pages:1135-1138.
 Howes PD, Chandrawati R, Stevens MM, 2014, Colloidal nanoparticles as advanced biological sensors, Science, 2013, Vol:346, DOI: 10.1126/science.1247390.
9:00 AM - NM05.01.03
Synthesis of Octahedral PtNiCu Ternary Alloy Nanostructure as Efficient Electrochemical Catalyst
University of California, Los Angeles1Show Abstract
Platinum-nickel (Pt-Ni) octahedral based nanomaterials represent an emerging class of highly active electrochemical catalysts, but can not meet the increasing activity demand for broad application and suffer from stability issue. We introduced Cu into octahedral Pt-Ni with controlled morphology. The octahedral Pt-Ni-Cu shows significantly enhanced activity and stability compared to octahedral Pt-Ni catalysts for cathode oxygen reduction reaction (ORR) , which is demonstrated to be a potential electrochemical catalyst. Computational simulation confirmed that the presence of Cu can improve the transition metal (Ni and Cu) retention thus improve both activity and stability.
9:15 AM - NM05.01.04
Synthesis and Chemical Transformation of Ni Nanoparticles Embedded in Silica
Joseph Tracy1,Brian Lynch1,Bryan Anderson1,2,3,W. Kennedy3
North Carolina State University1,Universal Technology Corporation2,Air Force Research Laboratory3Show Abstract
Ni nanoparticles (NPs) catalyze many chemical reactions, in which they can become contaminated or agglomerate, resulting in poorer performance. We report deposition of silica (SiO2) onto Ni NPs from tetraethyl orthysilicate (TEOS) through a reverse microemulsion approach, which is accompanied by an unexpected etching process. Ni NPs with an initial average diameter of 27 nm were embedded in composite SiO2-overcoated Ni NPs (SiO2-Ni NPs) with an average diameter of 30 nm. Each SiO2-Ni NP contained a ~7-nm oxidized Ni core and numerous smaller oxidized Ni NPs with diameters of ~2 nm distributed throughout the SiO2 shell. Etching of the Ni NPs is attributed to use of ammonium hydroxide as a catalyst for deposition of SiO2. Aliquots acquired during the deposition and etching process reveal agglomeration of SiO2 and Ni NPs, followed by dissociation into highly uniform SiO2-Ni NPs. This etching and embedding process may also be extended to other core materials. The stability of SiO2-Ni NPs was also investigated under high-temperature oxidizing and reducing environments. The structure of the SiO2-Ni NPs remained significantly unchanged after both oxidation and reduction, which suggests structural durability when used for catalysis.