Open Access. Powered by Scholars. Published by Universities.®

Analytical Chemistry Commons

Open Access. Powered by Scholars. Published by Universities.®

1875 Full-Text Articles 2379 Authors 298810 Downloads 82 Institutions

All Articles in Analytical Chemistry

Faceted Search

1875 full-text articles. Page 1 of 46.

Triple Pulse Amperometry: A Method Of Detection Of Carbohydrates And Alcohols For Liquid Chromatography , Scott Hughes 2017 Iowa State University

Triple Pulse Amperometry: A Method Of Detection Of Carbohydrates And Alcohols For Liquid Chromatography , Scott Hughes

Scott Hughes

Application of a triple pulse waveform is described for the anodic detection of simple alcohols and carbohydrates at a platinum electrode. The execution of the waveform incorporates the cleaning and reactivation of the platinum electrode, by alternate anodic and cathodic polarization, with measurement of the faradaic signal for the analyte at the reduced electrode surface. The waveform is completed within 0.5-1.5 s and the sampled faradaic signal exhibits no decay with time as would be the case for amperometric detection at a constant applied potential. Calibration curves made by plotting -1/I vs. 1/C are linear. This ...


Engineering Fret Biosensors For Microrna Presence/Absence Analysis, Nicholas E. Larkey, Sean M. Burrows 2017 Oregon State University

Engineering Fret Biosensors For Microrna Presence/Absence Analysis, Nicholas E. Larkey, Sean M. Burrows

Biomedical Engineering Western Regional Conference

No abstract provided.


Energetic Effects Of Hole Transporting Materials On The Performance Of Organometal Halide Perovskite Photovoltaic Cells, So Min Park 2017 University of Kentucky

Energetic Effects Of Hole Transporting Materials On The Performance Of Organometal Halide Perovskite Photovoltaic Cells, So Min Park

Theses and Dissertations--Chemistry

Efficient, inexpensive, lightweight and flexible solar cells are desired to help meet the world’s growing energy needs. Organometal halide perovskite (OMHP) photovoltaic (PV) cells have shown dramatic increases in solar cell efficiencies increase over the last 5 years. OMHP PV cells have attracted significant attention due to their broad absorption spectra, high electron and hole mobility, and low production cost. The interface between hole transporting layer (HTL) and perovskite thin films have a significant influence on charge transfer and overall solar cell performance. 2,2’,7,7’-tetrakis(N,N-di-p-methoxyphenylamine)9,9’-spirobifluorene (Spiro-OMeTAD) is a small molecule largely ...


Analysis Of Gold Nanoparticles And Their Use With Laser Desorption/Ionization Mass Spectrometry, Alyssa Marsico 2017 University of Massachusetts - Amherst

Analysis Of Gold Nanoparticles And Their Use With Laser Desorption/Ionization Mass Spectrometry, Alyssa Marsico

Doctoral Dissertations May 2014 - current

Gold nanoparticles (AuNPs) have many unique properties that make them attractive for use in various biological applications. Laser desorption/ionization mass spectrometry (LDI-MS) has been used to monitor AuNPs in complex biological samples but there are still many ways in which AuNPs can be used with MS. In this dissertation, the use of AuNPs to assist in analyte ionization has been investigated. Their ability to enhance signal from biomolecules based on their surface chemistry, size, aggregation and method of deposition has been studied. The first use of an inkjet printer to create surfaces from which analytes can be sampled is ...


Gold Nanoparticle Biodistributions And Stability In Vivo From Mass Spectrometric Imaging, SUKRU GOKHAN ELCI 2017 University of Massachusetts - Amherst

Gold Nanoparticle Biodistributions And Stability In Vivo From Mass Spectrometric Imaging, Sukru Gokhan Elci

Doctoral Dissertations May 2014 - current

Their smaller size, inherent non-toxicity and tunable properties of gold nanoparticles (AuNPs) attract researchers for their use in biological applications such as drug delivery, imaging and therapeutics. Understanding the in vivo fate of these AuNPs are essential for their potential effects in both the environment and the body. In this dissertation, mass spectrometric imaging methods using laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) and laser desorption/ionization (LDI-MS) have been investigated to monitor the in vivo fate of AuNPs. AuNP injected mouse tissue samples can be obtained and readily imaged to track the injected AuNPs using these methods. A first-ever ...


Ryan Caylor, Ryan Caylor 2016 Concordia University - Portland

Ryan Caylor, Ryan Caylor

Matthew E. Wise

Determination of the optical and physical properties of secondary organic aerosol particles
Measurement of the peroxide content of secondary organic aerosol particles


Cole Crosby, Cole Crosby 2016 Concordia University - Portland

Cole Crosby, Cole Crosby

Matthew E. Wise

Measurement of NOx concentrations on the Concordia University campus
Assessment of ozone formation in sparsely monitored areas using passive sampling


Avery Hong, Avery Hong 2016 Concordia University - Portland

Avery Hong, Avery Hong

Matthew E. Wise

Measurement of NOx concentrations on the Concordia University campus


Preparation Of Derivatized Polyaniline For Biosensing Applications, Tiana C. Shaw 2016 Clark Atlanta University

Preparation Of Derivatized Polyaniline For Biosensing Applications, Tiana C. Shaw

Electronic Theses & Dissertations Collection for Atlanta University & Clark Atlanta University

Conducting polymers have emerged as a promising material for optoelectronics and chemical sensing application. Polyaniline (PANI) is a conductive polymer which can be easily functionalized to be specific for various biomolecules and has ideal sensor characteristics. The protonation and deprotonation of the polyaniline’s backbone by derivatization can result in color and conductive change responses. This makes it ideal for the construction of a real time, naked eye sensor. Derivatized polyaniline has previously been reported as a colorimetric sensor in solution. We plan to create a more practical sensor by synthesizing hydroxyl functionalized polyaniline thin films. In this study, we ...


Polyol Induced Partitioning Of Essential Oils In Aqueous Organic Solvent Mixtures, Thomas DelMastro 2016 Seton Hall University

Polyol Induced Partitioning Of Essential Oils In Aqueous Organic Solvent Mixtures, Thomas Delmastro

Seton Hall University Dissertations and Theses (ETDs)

Polyol Induced Extraction (PIE) was developed and patented at Seton Hall University by Drs. John R. Sowa Jr., Wyatt R. Murphy, and Mithilesh Deshpande. It was originally discovered and implemented as a method to recycle and reuse waste acetonitrile during the production shortage in 2008. Through the use of PIE, a solvent mixture containing acetonitrile and water can be separated by employing a polyol mass separating agent, which induces a phase separation. The system is separated into its corresponding aqueous and organic phases, with the organic phase being a highly purified organic liquid. Based on the successful experimental results that ...


Development Of An F-Element Separation Chemistry Using Solid Electrolytes, Kristian Guy Myhre 2016 University of Tennessee, Knoxville

Development Of An F-Element Separation Chemistry Using Solid Electrolytes, Kristian Guy Myhre

Doctoral Dissertations

The f‒elements (lanthanides and actinides) have numerous applications and are critically important to many industries, including the energy, security, and medical industries. One of the barriers to increased use and availability of the f‒elements is the difficulty in separating them from each other due to their similar chemistries. This is especially true of the trivalent f‒elements (lanthanides and minor actinides). The development of separation techniques that maximize the differences in the physicochemical properties of the f‒elements is therefore an important area of research. For these reasons, an effort was undertaken to explore the use of solid ...


Graphene Quantum Dots Electrochemistry And Development Of Sensitive Electrochemical Biosensor [Hybrid Poster 1-B], Tyler Smith, Alexander Banaszak 2016 Western Kentucky University

Graphene Quantum Dots Electrochemistry And Development Of Sensitive Electrochemical Biosensor [Hybrid Poster 1-B], Tyler Smith, Alexander Banaszak

Posters-at-the-Capitol

Graphene quantum dots (GQDs) are zero-dimensional material derived from graphene derivatives with characteristics from the structure of graphene with quantum confinement and edge effects possessing unique properties. Intense research activity in GQDs is attributed to their novel physical-chemical phenomena arising from the sp2-bonded carbon core surrounded with edge functional moieties. In this work, GQDs of optimal 5-7 nm size are investigated for their fundamental electrochemical properties and use in electrochemical sensing including enzyme-based glucose biosensor. Glucose oxidase (GOx) was immobilized on GQDs modified glassy carbon (GC) and the UV-Vis absorption and fluorescence spectroscopy, electron microscopy, cyclic and ...


P-26 Detection Of Counterfeit Antimalarial Drugs By Sers, Getahun Merga, P. Shepard, M. Trujillo, J. Camden 2016 Andrews University

P-26 Detection Of Counterfeit Antimalarial Drugs By Sers, Getahun Merga, P. Shepard, M. Trujillo, J. Camden

Celebration of Research and Creative Scholarship

Substandard antimalarial drugs are a major problem to the health of citizens in developing countries, and it is likely that the problem persists due to the lack of means to detect substandard drugs. Various colorimetric techniques have been implemented to determine if a drug contains the stated active ingredient or not, but vibrational spectroscopies such as NIR and Raman can be used to more reliably quantify the amount of active ingredient. The use of Raman, however, has been limited by the presence of significant sample fluorescence that interferes with detection of the SERS signals of the active ingredients. Thus, we ...


Quantitative Analysis Of Acetylsalicylic Acid By Q-Nmr (Quantitative-Nuclear Magnetic Resonance Spectroscopy), Charles Flemming Jr. 2016 Governors State University

Quantitative Analysis Of Acetylsalicylic Acid By Q-Nmr (Quantitative-Nuclear Magnetic Resonance Spectroscopy), Charles Flemming Jr.

All Student Theses

Quantitative analysis is an important step during pharmaceutical drug development. Currently, the pharmaceutical industry uses high performance liquid chromatography (HPLC) for quantitative analysis of organic compounds as the preferred technique. The proton nuclear magnetic resonance (NMR) technique has an inherent ability to quantify a given analyte and may be used to quantify organic compounds. Quantitative nuclear magnetic resonance spectroscopy (q-NMR) of acetylsalicylic acid (ASA) was conducted using tert-butyl alcohol (tert-butanol) as the internal standard and deuterated chloroform (CDCl3) as the solvent. Preparations of ASA solutions in low and high concentration ranges, 1.0 mM – 10.1 mM ...


The Investigation Of The Electrical Control Of Hemimicelles And Admicelles On Gold For Analyte Preconcentration, Dheyaa Hussein Al-Karawi 2016 Western Kentucky University

The Investigation Of The Electrical Control Of Hemimicelles And Admicelles On Gold For Analyte Preconcentration, Dheyaa Hussein Al-Karawi

Masters Theses & Specialist Projects

Hemimicelles and admicelles are well-investigated wonders in modern science; they are surfactant monolayers and surface adsorbed micelles, respectively. Capacitance measurements for monitoring the formation of dodecyl sulfate (DS) surfactant monolayer on positively charged gold substrates (planar gold) and the adsorbance of 2-naphthol onto DS surfactant monolayer were performed. The investigation of the electrical control of DS at various concentrations (4, 6, 16, and 32 mM) below and above the critical micelle concentration (CMC= 8 mM) on gold surfaces for analyte preconcentration, prior to chromatographic analysis, is presented. Charged ionic surfactants, such as DS, drawn to a surface of opposite charge ...


Electrochemical Nanoprobes For Electron Transfer Kinetics And Electrocatalysis Study, Yun Yu 2016 The Graduate Center, City University of New York

Electrochemical Nanoprobes For Electron Transfer Kinetics And Electrocatalysis Study, Yun Yu

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

The studies of electrochemical processes on the nanoscale have led to a significant progress in understanding of electrochemical mechanisms and characterization of nanomaterials in the fields of energy, catalysis, and biological research. Electrochemical experiments at nanoscale require the fabrication and characterization of nanometer-sized electrochemical probes. The main advantages of the nanoprobes include very fast mass-transfer rate, high signal-to-noise ratio and extremely fine spatial resolution of electrochemical imaging. In the course of my Ph.D. research, different types of electrochemical probes were developed for measuring electron-transfer kinetics, probing single catalytic nanoparticles and sampling ultra-small volume of liquids.

We developed methodologies to ...


Investigating Mycotoxins And Secondary Metabolites In Canadian Agricultural Commodities Using High-Resolution Mass Spectrometry, Megan J. Kelman 2016 The University of Western Ontario

Investigating Mycotoxins And Secondary Metabolites In Canadian Agricultural Commodities Using High-Resolution Mass Spectrometry, Megan J. Kelman

Electronic Thesis and Dissertation Repository

Mycotoxins are secondary metabolites produced by fungi, which are harmful to humans and/or animals. Alternaria is a common fungal plant pathogen that can produce mycotoxins in agricultural commodities, such as processed wheat products, and fruit juices. Liquid chromatography mass spectrometry (LC-MS) is commonly used for the detection, characterization and quantitation of mycotoxins in agricultural products. Canadian Alternaria species were assessed to provide a risk assessment of their secondary metabolites in agricultural products by describing their global metabolome data obtained from the Orbitrap LC-MS instrument. Combination of this high mass accuracy data with post data-acquisition analysis techniques resulted in the ...


Fabricating And Characterizing Chalcogenide Thin Films As Light Absorbing Layers In Solar Cells, Daniel Vaccarello 2016 The University of Western Ontario

Fabricating And Characterizing Chalcogenide Thin Films As Light Absorbing Layers In Solar Cells, Daniel Vaccarello

Electronic Thesis and Dissertation Repository

Solar cell development has been a focus in energy research, with light-absorbing layers as the key theme. Copper indium disulphide (CuInS2) and copper zinc tin sulphide (Cu2ZnSnS4 or CZTS) have energy band gaps that are optimal for solar energy conversion. New preparation methods have been developed with practicality, safety, and low costs in mind. The one-pot method developed in this thesis group has been utilized to create nanocrystals that can be used to absorb light and generate current. The use of low temperatures and minimalistic reaction conditions has led to the production of CIS and CZTS ...


First Line Shape Analysis And Spectroscopic Parameters For The Ν11 Band Of 12c2h4, Et-touhami Es-sebbar, John JohnMantzaras, Yves Benilan, Aamir Farooq 2016 Paul Scherrer Institute (PSI)

First Line Shape Analysis And Spectroscopic Parameters For The Ν11 Band Of 12c2h4, Et-Touhami Es-Sebbar, John Johnmantzaras, Yves Benilan, Aamir Farooq

Dr. Et-touhami Es-sebbar

An accurate knowledge of line intensities, collisional broadening coefficients and narrowing parameters is necessary for the interpretation of high-resolution infrared spectra of the Earth and other planetary atmospheres. One of the most promising spectral domains for 12C2H4 monitoring in such environments is located near the 3.36 µm window, through its ν11 C–H stretching mode. In this paper, we report an extensive study in which we precisely determine spectroscopic parameters of 12C2H4 ν11 band at 297±1 K, using a narrow Difference-Frequency-Generation (DFG) laser with 10−4 cm−1 resolution. Absorption measurements were performed in the 2975–2980 cm ...


Comparative Analysis Of In Situ Fibronectin Using Tof-Sims, Spi-Ms, And Dropdesi-Ms In A Microfluidic Reactor, Shannon Fasing, Xiao-Ying Yu, Juan Yao, Jiachao Yu 2016 Pacific Northwest National Laboratory

Comparative Analysis Of In Situ Fibronectin Using Tof-Sims, Spi-Ms, And Dropdesi-Ms In A Microfluidic Reactor, Shannon Fasing, Xiao-Ying Yu, Juan Yao, Jiachao Yu

STAR (STEM Teacher and Researcher) Presentations

Fibronectin is an important biomolecule due to its role in cell differentiation, growth, kinesis, and adhesion. Such biological responses are mediated through membrane recognition and signaling; where fibronectin is found. Studying the outer molecular surface of fibronectin allows deeper insight into the microbiological reactions that occur during these processes. In situ mass spectrometry analysis in aqueous solution accurately represents fibronectin’s chemical components, made possible by a vacuum compatible microfluidic reactor, SALVI (System for Analysis at the Liquid Vacuum Interface). SALVI was paired with the analytical tools: time-of-flight secondary ion mass spectrometer (ToF-SIMS), single photon ionization mass spectrometer (SPI-MS) and ...


Digital Commons powered by bepress