A5027769343- Methane Hydrates and Related Phenomena
- Geophysics and Gravity Measurements
- Ionosphere and magnetosphere dynamics
- Seismic Waves and Analysis
- Earthquake Detection and Analysis
- Mass Spectrometry Techniques and Applications
- Astrophysics and Cosmic Phenomena
- Solar and Space Plasma Dynamics
- Seismology and Earthquake Studies
- Analytical Chemistry and Chromatography
- Microfluidic and Capillary Electrophoresis Applications
- Advanced Proteomics Techniques and Applications
- Ion-surface interactions and analysis
- Electrohydrodynamics and Fluid Dynamics
- Metabolomics and Mass Spectrometry Studies
- Analytical chemistry methods development
- Advanced Chemical Sensor Technologies
- Glycosylation and Glycoproteins Research
- Advanced biosensing and bioanalysis techniques
- Nanoplatforms for cancer theranostics
- Superconducting Materials and Applications
- Advanced Nanomaterials in Catalysis
- Analytical Chemistry and Sensors
- Innovative Microfluidic and Catalytic Techniques Innovation
- Catalytic C–H Functionalization Methods
Ningbo University
2018-2025
Pacific Northwest National Laboratory
2015-2024
Richland College
2003-2018
Battelle
2016
Environmental Molecular Sciences Laboratory
2004-2014
Owlstone Medical (United Kingdom)
2009
Harvard University
2008
Massachusetts General Hospital
2008
Texas A&M University
2007
Purdue University West Lafayette
2006
Measurements of the charge and size heptane droplets generated by electrostatic sprays showed that droplet charge-to-volume ratio is a monotonically decreasing function size. In useful range electrospray operation, characterized smaller than orifice from which liquid issued, it was found larger were closer they to Rayleigh limit. particular, when had charging levels between 70% 80% such limit, observed rupture because repulsive force due surface evidently overcame tension. The phenomenon,...
Abstract The electrodynamic ion funnel has enabled the manipulation and focusing of ions in a pressure regime (0.1–30 Torr) that challenged traditional approaches, provided basis for much greater mass spectrometer transmission efficiencies. initial implementations aimed to efficiently capture expanding gas jet an electrospray ionization interface radially focus them efficient transfer through conductance limiting orifice. We review improvements fundamental understanding motion funnels,...
Sensitive detection of low-abundance proteins in complex biological samples has typically been achieved by immunoassays that use antibodies specific to target proteins; however, de novo development is associated with high costs, long lead times, and failure rates. To address these challenges, we developed an antibody-free strategy involves PRISM (high-pressure, high-resolution separations coupled intelligent selection multiplexing) for sensitive selected reaction monitoring (SRM)–based...
The utility of ion mobility spectrometry (IMS) for separation mixtures and structural characterization ions has been demonstrated extensively, including in biological nanoscience contexts. A major attraction IMS is its speed, several orders magnitude greater than that condensed-phase separations. Nonetheless, combined with mass (MS) remained a niche technique, substantially because limited sensitivity resulting from losses at the IMS-MS junction. We have developed new electrospray ionization...
An experimental study has been performed on the structure of an electrostatic spray monodisperse droplets. Such a is established when liquid with sufficient electric conductivity and moderate surface tension, in present case heptane doped antistatic additive, fed through small metal tube maintained at several kilovolts relative to ground electrode few centimeters away. The meniscus outlet capillary takes conical shape under action field, thin jet emerging from cone tip. This breaks up into...
An experimental investigation and theoretical analysis are reported on charge competition in electrospray ionization (ESI) its effects the linear dynamic range of ESI mass spectrometric (MS) measurements. The experiments confirmed expected increase MS sensitivities as flow rate decreases. However, different compounds show somewhat spectral peak intensities even at lowest rates, same concentration operating conditions. response for each compound solution shows good linearity lower...
The ionization and transmission efficiencies of an electrospray (ESI) interface were investigated to advance the understanding how these factors affect mass spectrometry (MS) sensitivity. In addition, effects ES emitter distance inlet, solution flow rate, inlet temperature characterized. Quantitative measurements current loss throughout ESI accomplished by electrically isolating front surface from inner wall heated capillary, enabling losses on two surfaces be distinguished. lost was...
The ability to effectively focus and transmit ions from relatively high pressure ion sources is a key factor that affects sensitivity dynamic range in mass spectrometry. To improve upon the spectrometric achievable with electrospray ionization novel funnel interface has been developed implemented triple quadrupole spectrometer. consists of series ring electrodes progressively smaller internal diamter which RF DC electric fields are co-applied. create pseudo-potential causing collisionally...
We have developed a new procedure for fabricating fused-silica emitters electrospray ionization-mass spectrometry (ESI-MS) in which the end of bare capillary is immersed into aqueous hydrofluoric acid, and water pumped through to prevent etching interior. Surface tension causes etchant climb exterior, etch rate resulting meniscus decreases as function distance from bulk solution. Etching continues until silica touching acid reservoir completely removed, essentially stopping process. The no...
An experimental investigation was performed on electrosprays of low electric conductivity liquids (heptane with different amounts an antistatic additive) that were operated in the cone-jet mode. The effects liquid flow rate, applied voltage, and droplet size spray monodispersity systematically investigated. found to be dominantly controlled by rate secondarily voltage. It showed no dependence capillary size. For a given liquid, stable monodisperse could established only within certain ranges...
Field asymmetric waveform ion mobility spectrometry (FAIMS) has emerged as a powerful tool of broad utility for separation and characterization gas-phase ions, especially in conjunction with mass (MS). In FAIMS, ions are filtered by the dependence on electric field while being carried gas flow through analytical gap between two electrodes either planar (p-) or cylindrical (c-) geometry. Most FAIMS/MS systems employ c-FAIMS because its ease coupling to MS, yet merits geometries have not been...
Tumor-derived exosomes, which contain RNA, DNA, and proteins, are a potentially rich non-invasive source of biomarkers. However, no efficient isolation or detection methods yet available. Here, we developed microfluidic Raman biochip designed to isolate analyze exosomes in situ. Anti-CD63 magnetic nanoparticles were used enrich through mixing channels staggered triangular pillar array. EpCAM-functionalized Raman-active polymeric nanomaterials (Raman beads) allow rapid analysis exosome...
A new ultrahigh resolution ion mobility platform enables the fast separation and characterization of isomeric glycoforms.
A novel visible-light-catalyzed tandem radical addition/1,5-hydrogen atom transfer/cyclization cascade of 2-alkynylarylethers with sulfonyl chlorides in 2-methyltetrahydrofuran was developed under photocatalyst- and additive-free conditions. This reaction relies on unique energy transfer solvent-radical relay strategies to generate radicals for the preparation a series sulfonyl-functionalized dihydrobenzofurans moderate high yields catalyzed by visible light or solar radiation.
Abstract Electrical stimulation (ES) is proposed as a therapeutic solution for managing chronic wounds. However, its widespread clinical adoption limited by the requirement of additional extracorporeal devices to power ES‐based wound dressings. In this study, novel sandwich‐structured photovoltaic microcurrent hydrogel dressing (PMH dressing) designed treating diabetic This innovative comprises flexible organic (OPV) cells, micro–electro–mechanical systems (MEMS) electrode, and...
Abstract Bioenergetic therapy is emerging as a promising therapeutic approach. However, its effectiveness restricted by metabolic plasticity, tumor cells switch phenotypes between glycolysis and oxidative phosphorylation (OXPHOS) to compensate for energy. Herein, Metformin (MET) BAY‐876 (BAY) co‐loaded CuFe 2 O 4 (CF) nanoplatform (CFMB) developed boost energy deprivation synchronous interventions of OXPHOS bioenergetic synergetic with chemodynamic/photothermal (CDT/PTT). The MET can...
The radical relay provides an effective paradigm for intermolecular assembly to achieve functionalization across remote chemical bonds. Herein, we report the first 1,3-carbocarbonylation of α-carbonyl alkyl bromides two separate C═C reaction is highly chemo- and regioselective, with C(sp3)–C(sp3) bonds one C═O bond formed in a single orchestrated operation. In addition, synthesis method under mild conditions using inexpensive copper as catalyst allows facile access structurally diverse...
In this study, high-efficiency packed capillary reversed-phase liquid chromatography (RPLC) coupled on-line with high-performance Fourier transform ion cyclotron resonance (FTICR) mass spectrometry has been investigated for the characterization of complex cellular proteolytic digests. Long columns (80-cm) small (3-μm) C18 bonded particles provided a total peak capacity ∼1000 polypeptides when interfaced an ESI-FTICR spectrometer under composition gradient conditions at pressure 10 000 psi....
We describe the application of capillary liquid chromatography (LC) time-of-flight (TOF) mass spectrometric instrumentation for rapid characterization microbial proteomes. Previously (Lipton et al., Proc. Natl. Acad. Sci. U.S.A. 2002, 99, 11049) peptides from a series growth conditions Deinococcus radiodurans have been characterized using LC MS/MS and accurate measurements which are captured as an time (AMT) tag database. Using this AMT database, detected can be assigned obtained on TOF due...
The feasibility of producing relatively monodisperse and biologically active insulin particles by electrospray drying is demonstrated. process entails dissolving dry in an acidic ethanol–water solution. solution then electrosprayed and, after solvent evaporation, residues can be collected on suitable deposition substrates. Particles were sized visually, using a scanning electron microscope (SEM), aerodynamically, inertial impactor. When electrosprays nearly saturated solutions operated the...
Arrays of microelectrospray emitters were fabricated on polycarbonate substrates using a laser etching technique. Stable multielectrosprays successfully generated in the liquid flow rate range relevant to mass spectrometric applications. Comparison electrosprays from microfabricated emitter array and conventional fused-silica capillaries showed similar spray characteristics reliability. Higher total electrospray ion currents observed as number increased at given rate. Consistent with...