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Synthesis, Spectroscopic Characterization, And Genotoxicity Of A New Group Of Azo-Oxime Metal Chelates, Beyza Cabi̇r, Bariş Avar, Mehmet Gülcan, Ahmet Kayraldiz, Mükerrem Kurtoğlu Jan 2013

Synthesis, Spectroscopic Characterization, And Genotoxicity Of A New Group Of Azo-Oxime Metal Chelates, Beyza Cabi̇r, Bariş Avar, Mehmet Gülcan, Ahmet Kayraldiz, Mükerrem Kurtoğlu

Turkish Journal of Chemistry

A new azo-oxime ligand, 2-[(E)-(hydroxyimino)methyl]-4-[(E)- (4-nitrophenyl)diazenyl]phenol, (pxoxH_2) (2), was prepared by condensation of hydroxylamminehydrochloride and 2-hydroxy5- [(4-nitrophenyl)diazenyl]benzaldehyde (1) with treatment of a solution of diazonium salt of p-nitroaniline and 2-hydroxybenzaldehyde in ethanol. The 6 coordination compounds, [Mn(pxoxH)_2(H_2O)_2].H_2O (3), [Co(pxoxH)_2(H_2O)_2].4H_2O (4), [Ni(pxoxH)_2(H_2O)_2].2H_2O (5), [Cu(pxoxH)_2].H_2O (6), [Zn(pxoxH)_2].6H_2O (7), and [Cd(pxoxH)_2(H_2O)_2].H_2O (8), were prepared by reacting Mn(II), Ni(II) Cu(II), Co(II), Zn(II), and Cd(II) ions with the ligand. The structures of the compounds were elucidated from the elemental analysis data and spectroscopic studies. The azo-oxime metal complexes were also characterized by XRD, magnetic moment, molar conductivity, and thermal analyses. Elemental analyses of the chelates …


Flavonoid Constituents Of Sideritis Caesarea, Belkis Halfon, Ece Çi̇ftçi̇, Gülaçti Topçu Jan 2013

Flavonoid Constituents Of Sideritis Caesarea, Belkis Halfon, Ece Çi̇ftçi̇, Gülaçti Topçu

Turkish Journal of Chemistry

The acetone extract of the aerial parts of Sideritis caesarea Duman, Aytaç & Başer (Lamiaceae) afforded the flavonoids penduletin (1) and apigenin (2) and 6 glycosylated flavonoids, 4'-O-methyl-isoscutellarein-7-O-[6'''-O-acetyl-\beta-D-allopyranosyl- (1 \to 2)]-6\"-O-acetyl-\beta -D-glucopyranoside (3), 4'-O-methylhypolaetin- 7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-6\"-O-acetyl-\beta- D-glucopyranoside (4), isoscutellarein-7-O-[6'''-O-acetyl-\beta- D-allopyranosyl-(1 \to 2)]-6\"-O-acetyl-\beta -D-glucopyranoside (5), isoscutellarein-7-O-[6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]- \beta-D-glucopyranoside (6), 4'-O-methylhypolaetin-7-O- [6'''-O-acetyl-\beta -D-allopyranosyl-(1 \to 2)]-\beta-D- glucopyranoside (7), and hypolaetin-7-O-[6'''-O-acetyl-\beta- D-allopyranosyl-(1 \to 2)]-\beta -D-glucopyranoside (8). The compounds were identified by the use of 1D- and 2D-NMR and UV spectroscopic techniques and by comparisons with the reported data. The acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities of the acetone, methanol, …


Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ Jan 2013

Quasielastic Light Scattering Studies Of Polypeptides: Evidence For Chain Extension In Solution, Mehmet Bahatti̇n Baysal, Çi̇ğdem Karadağ

Turkish Journal of Chemistry

Dynamic light scattering and viscosimetric methods were used to study polypeptides including polyleucine, poly (\gamma-benzyl-L-glutamate), poly (\alpha-L-glutamic acid), and polyproline II. Chain extension showing rod-like and flexible conformations occurred in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions as these solutions were diluted in glacial acetic acid or in a mixed solvent of acetic acid and dichloromethane. The elongation of chains in poly(\gamma -benzyl-L-glutamate) and polyproline II solutions was studied by dynamic light scattering and viscosimetric methods. This nonenzymatic growth of peptide chains provides data on primordial synthesis of protein molecules in the absence of cell machinery and for this reason these …


Synthesis Of Fused Tetrazolone Derivatives, Sevi̇l Özcan, Zeynep Ekmekçi̇, Berk Müjde, Meti̇n Balci Jan 2013

Synthesis Of Fused Tetrazolone Derivatives, Sevi̇l Özcan, Zeynep Ekmekçi̇, Berk Müjde, Meti̇n Balci

Turkish Journal of Chemistry

New fused tetrazolone derivatives were synthesized using homophthalic and maleic anhydrides. Treatment of anhydrides with trimethylsilyl azide opened the lactone rings and formed the corresponding intermediates, which bore 1,3-dipole and dipolarophile functionalities in ortho positions. The intermediates partially underwent internal 1,3-dipolar cycloaddition to produce fused tetrazolone derivatives. When the carbonyl groups in anhydride were not conjugated with any double bond, then a triazine-fused tetrazolone derivative was formed.


Ultrasound-Assisted Emulsification--Solidified Floating Organic Drop Microextraction Combined With Flow Injection--Flame Atomic Absorption Spectrometry For The Determination Of Palladium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Mooud Amirkavei Jan 2013

Ultrasound-Assisted Emulsification--Solidified Floating Organic Drop Microextraction Combined With Flow Injection--Flame Atomic Absorption Spectrometry For The Determination Of Palladium In Water Samples, Shayessteh Dadfarnia, Ali Mohammad Haji Shabani, Mooud Amirkavei

Turkish Journal of Chemistry

The ultrasound-assisted emulsification--solidified floating organic drop microextraction (USAE--SFODME) methodology was combined with flow injection--lame atomic absorption spectrometry (FI--FAAS) for the separation/pre\-concentration and determination of palladium at ultratrace level. In this method, the palladium ion in the aqueous solution was complexed with acetylacetone (6 \times 10^{-3} mol L^{-1}) in the pH range of 1--7 and was extracted into 40 \mu L of 1-undecanol, which was sonically dispersed in the aqueous phase. The vial was then centrifuged and cooled in an ice bath for 5 min. The solidified extract was melted and diluted to 100 \mu L with a solution of hydrochloric …


Synthesis And Biological Activities Of Methylenebis-4h-1,2,4-Triazole Derivatives, Yildiz Uygun, Hacer Bayrak, Havva Özkan Jan 2013

Synthesis And Biological Activities Of Methylenebis-4h-1,2,4-Triazole Derivatives, Yildiz Uygun, Hacer Bayrak, Havva Özkan

Turkish Journal of Chemistry

5,5'-Methylenebis(4--phenyl-4H-1,2,4-triazole-3-thiol) (2) was synthesized starting from hydrazinecarbothioamide compound (1). Treatment of compound 2 with ethyl bromoacetate produced diethyl 5,5'-{methylenebis[(4-phenyl-4H-1,2,4-triazole-5,3-diyl)thio]}diacetate (3), which was converted to the corresponding diacetohydrazide derivative (4) by treatment with hydrazine hydrate. The reaction of compound 4 with several aldehydes produced the corresponding arylidene hydrazides, 5a--d. Syntheses of Mannich bases 6a--c were carried out by the treatment of compound 2 with several amines in the presence of formaldehyde. (4{[5-({5-[(4-Amino-2-chlorophenyl)thio]-4-phenyl-4H-1,2,4-triazol-3-ylmethyl)-4-phenyl-4H-1,2,4-triazol-3-yl]thio}-3-chlorophenyl)amine (8) was prepared by reduction of 2 nitro groups of 3,3' -methylenebis{5-[(2-chloro-4-nitrophenyl)thio]-4-phenyl-4H-1,2,4-triazole} (7) that were obtained from the condensation of 2} with 3,4-dichloronitrobenzene. The newly synthesized compounds were screened …


A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz Jan 2013

A New Anthracene Derivative Of Calix[4]Arene As A Fluorescent Chemosensor, Özlem Şahi̇n, Mustafa Şahi̇n, Nuri̇ye Koçak, Mustafa Yilmaz

Turkish Journal of Chemistry

A new anthracene derivative of calix[4]arene was synthesized as a highly fluorescent compound. This compound was examined for its fluorescent properties towards different metal ions (Li^+, Na^+, Mg^{2+}, Ca^{2+}, Ba^{2+}, Ni^{2+}, Cu^{2+}, Zn^{2+}, Pb^{2+}) by UV and fluorescence spectroscopy. On complexation by alkaline earth metal cations and transition metal cations, the fluorescence spectrum was quenched. In particular, Ca^{2+} caused greater than 98% quenching of the anthracene derivative of calix[4]arene.


Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia Jan 2013

Synthesis, Characterization, And Dft Calculation Of A Pd(Ii) Schiff Base Complex, Alireza Akbari, Zahra Alinia

Turkish Journal of Chemistry

The 4-((E)-(2-((E)-2, 4-dihydroxybenzylideneamino) ethylimino) methyl) benzene-1,3-diol tetradentate ligand, H_2L, reacted with PdCl_2 to produce the related complex. The complex was characterized by elemental analysis, infrared and electronic spectroscopy, thermogravimetric study, and molar conductance. Furthermore, the fully optimized geometries were calculated using the ADF 2009.01 package. Comparison between the calculated and experimental results covering molecular structures, assignment of fundamental vibrational modes, and thermodynamic properties were investigated. The optimized molecular geometries were compared with the experimental data obtained from X-ray data of a similar complex, which indicated that the theoretical results agree with the corresponding experimental values. The UV-Vis spectrum of the …


Synthesis, Characterization, And Fluorescence Study Of Phthalhydrazidylazo Derivative Of An Unsaturated Diketone And Its Metal Complexes, Radhika Pallikkavil, Muhammed Basheer Ummathur, Krishnannair Krishnankutty Jan 2013

Synthesis, Characterization, And Fluorescence Study Of Phthalhydrazidylazo Derivative Of An Unsaturated Diketone And Its Metal Complexes, Radhika Pallikkavil, Muhammed Basheer Ummathur, Krishnannair Krishnankutty

Turkish Journal of Chemistry

The coupling of diazotized luminol with the unsaturated diketone 1,7-diphenylhepta-4,6-diene-1,3-dione yielded a new type of tridentate ligand (H_2L). Analytical, IR, ^1H NMR, and mass spectral data indicate the existence of the compound in the intramolecularly hydrogen-bonded keto-hydrazone tautomeric form. Dibasic tridentate coordination of the compound in its [ML(H_2O)] complexes [M = Cu(II), Ni(II) and Zn(II)] was established on the basis of analytical and spectral data. The Ni(II) and Zn(II) chelates are diamagnetic while Cu(II) complex showed normal paramagnetic moment. The fluorescence maxima of the compound in different solvents show that the emission wavelength increases with increases in the polarity of …


Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran Jan 2013

Comparative Study Of Microwave-Assisted And Conventional Synthesis Of Ibuprofen-Based Acyl Hydrazone Derivatives, Ayşe Uzgören Baran

Turkish Journal of Chemistry

A series of potential biological active acyl hydrazone derivatives containing ibuprofen moiety (compounds 4a--4p) was synthesized by the condensation of ibuprofen hydrazone with aromatic aldehydes using conventional and microwave irradiation methods. The microwave method was found to be successful with nearly the same or higher yields and shorter reaction time, and it was more environmentally friendly compared to the conventional heating method. The chemical structures of the synthesized compounds were characterized by IR, ^1H NMR, and APT-NMR spectroscopy.


Dynamic Passivation With Bsa Overcomes Ltcc Mediated Inhibition Of Pcr, Jason Besecker, Kenneth A. Cornell, Greg Hampikian Jan 2013

Dynamic Passivation With Bsa Overcomes Ltcc Mediated Inhibition Of Pcr, Jason Besecker, Kenneth A. Cornell, Greg Hampikian

Chemistry and Biochemistry Faculty Publications and Presentations

The increasing use of low temperature co-fired ceramic (LTCC) for the fabrication of biological microfluidic devices necessitates further research on LTCC biocompatibility. In this study we explore the inhibitory effect of DuPont's 951 LTCC on Polymerase Chain Reaction (PCR), and demonstrate a novel mechanism to increase biocompatibility between LTCC and PCR with the addition of a common passivation substance, bovine serum albumin (BSA). We show that DuPont's 951 LTCC binds negatively charged proteins including BSA and ovalbumin (OVA). This is a significant discovery as proteins (enzymes) are an essential component of most biological reactions, and a frequent addition to microfluidic …


Use Of Sweet Potato To Develop A Medium For Cultivation Of Lactic Acid Bacteria, Saeed A. Hayek Jan 2013

Use Of Sweet Potato To Develop A Medium For Cultivation Of Lactic Acid Bacteria, Saeed A. Hayek

Dissertations

This study investigated the use of sweet potatoes (Ipomoea batatas) as a basic component to develop a medium for cultivation of lactic acid bacteria (LAB). Extract from baked sweet potatoes was used to form a sweet potato medium (SPM). SPM was supplemented with 4 g/L of each nitrogen source (beef extract, yeast extract, and proteose peptone #3). Lactobacilli MRS was used as a control medium. Ten LAB strains were used to determine the suitability of SPM serving the growth of LAB. Our results showed no significant (p < 0.05) differences in the optical density, maximum specific growth rates, and bacterial populations between MRS and SPM. SPM also maintained higher pH values throughout the incubation period compared to that in MRS. The cost of SPM was 47% less than the cost of MRS. Further step was taken to determine the suitability of SPM serving LAB enzymatic activity. LAB strains growing in SPM showed relatively higher β-glucosidases, acid phosphatase, and phytase activities and lower a-glucosidase compared to that in MRS. Strains of L. reuteri showed the …


The Scope Of The Bis-Urea Macrocycle Assembly Motif, Michael F. Geer Jan 2013

The Scope Of The Bis-Urea Macrocycle Assembly Motif, Michael F. Geer

Theses and Dissertations

From the formation of rock candy crystals, to the functionality of DNA in the cell, to the cosmic dust throughout the universe, supramolecular chemistry has a great impact and importance in the world around us. In this thesis, we explore the supramolecular interactions and self-assembly of bis¬-urea macrocyclic systems and investigate how their structure and assembly influences bulk properties and functionality. Specifically, in chapter one, we review the factors that guide, limit, and define supramolecular structures from the atomic to the centimeter scale.

In chapter two, we investigate the incorporation of benzophenone, a well known triplet sensitizer, within a bis-urea …


Single Crystal To Single Crystal Polymerization Of A Columnar Assembled Diacetylene Macrocycle, Weiwei Xu Jan 2013

Single Crystal To Single Crystal Polymerization Of A Columnar Assembled Diacetylene Macrocycle, Weiwei Xu

Theses and Dissertations

Organic tubular materials have attracted lots of attentions for their potential applications as nanoscale fluidic transport systems, specific ion sensors, molecular sieves and confined molecular reaction containers. While conjugated polymers, due to delocalized Pi electrons, exhibit interesting solar cells and sensors applications. In this thesis, we developed a conjugated polymer which combines the attributes of conjugated polymers with tubular materials, which should have great potential to work as a sensing material.

We reproduced and scaled-up the synthesis of a polymerizable macrocycle 1 that contains two rigidly separated diacetylene units. We found that, through hydrogen bonding, 1 can assemble into columnar …


Instrument And Method Development For Single-Cell Classification Using Fluorescence Imaging Multivariate Optical Computing, Joseph Swanstrom Jan 2013

Instrument And Method Development For Single-Cell Classification Using Fluorescence Imaging Multivariate Optical Computing, Joseph Swanstrom

Theses and Dissertations

Multivariate optical computing (MOC) is an all-optical approach of predictive spectroscopy that utilizes multivariate calibration and spectral pattern recognition techniques while operating in a simple filter photometer instrument, removing the need for expensive instrumentation and post-processing of spectral data. This is accomplished with specially designed interference filters called multivariate optical elements (MOEs). MOC can provide analytical solutions for applications requiring low cost, rugged, and simple to operate instrumentation for use in remote and hazardous environments such as open ocean waters. These instrument specifications are central for developing a method for classifying phytoplankton in their natural environment. Phytoplankton are photosynthetic single …


Programmable Polymers Preparation Optimization And Applications On Solute Templates, Yinyan He Jan 2013

Programmable Polymers Preparation Optimization And Applications On Solute Templates, Yinyan He

Theses and Dissertations

Programmable polymer is a type of stimuli-responsive polymer which can keep their induced properties after removal of the stimulu, as well as programmable polymers maintain the general properties as stimuli-responsive polymers, such as recognize and respond to the stimulus. The previous reported solvent Caryl-Nimide bonds based programmable polymers (SPP-1) can freely rotate and change the carboxylic acid recognition group orientation in response to templates. Solvent templates were used in the SPP-1. One potential application for SPPs is using their recognition and memory properties for the identification and separation of mixture solutions of various analytes. In my first project, I wanted …


Comparative Evaluation Of N-Acetylcysteine And N-Acetylcysteine Amide In Acetaminophen-Induced Oxidative Stress, Ahdab Naeem Khayyat Jan 2013

Comparative Evaluation Of N-Acetylcysteine And N-Acetylcysteine Amide In Acetaminophen-Induced Oxidative Stress, Ahdab Naeem Khayyat

Masters Theses

"Acetaminophen (APAP) is the most widely used pharmaceutical analgesic-antipyretic agent in the world, but its toxicity is a common cause of drug-induced hepatotoxicity. With APAP toxicity, cellular glutathione (GSH) is depleted. This results in the availability of N-acetyl-p-benzoquinone imine (NAPQI), is a toxic metabolite of APAP that binds to cellular macromolecules, which leads to cell necrosis. N-acetyl cysteine (NAC), a GSH precursor, is the only approved antidote for an acetaminophen overdose. It is a negatively charged molecule that diminishes its penetration into the cells, thereby requiring fairly high doses that increase the severity of side effects. In addition, oral and …


Yellowstone Over-Snow Vehicle Emission Tests – 2012, John D. Ray, Gary A. Bishop, Brent G. Schuchmann, Chris Frey, Gurdas Sandhu, Brandon Graver Jan 2013

Yellowstone Over-Snow Vehicle Emission Tests – 2012, John D. Ray, Gary A. Bishop, Brent G. Schuchmann, Chris Frey, Gurdas Sandhu, Brandon Graver

Fuel Efficiency Automobile Test Publications

No abstract provided.


Synthesis And Characterization Of Biodegradable Poly(Vinyl Esters) With Hdac Inhibitory Activity, Kyle Lawrence Horton Jan 2013

Synthesis And Characterization Of Biodegradable Poly(Vinyl Esters) With Hdac Inhibitory Activity, Kyle Lawrence Horton

Wayne State University Theses

HDAC inhibitors are known to have anti-inflammatory properties. HDAC inhibitors are used in combination with Oct4 to generate induced pluripotent stem cells. I hypothesized that polyesters based on simple aliphatic HDAC inhibitors like valproic acid (VPA) and phenylbutyric acid (PBA) can serve as alternatives to existing polyester biomaterials with improved anti-inflammatory properties and as scaffolds for generation of iPSCs when used in combination with layer-by-layer thin films delivering reprogramming transcription factors. Vinyl ester of phenylbutyric acid (VEPA) and vinyl ester of valproic acid (VEVA) were synthesized from their carboxylic acid precursors using an iridium complex catalyst at yields as high …


Spliceosomal Prp24 Unwinds A Minimal U2/U6 Complex From Yeast, Chandani Manoja Warnasooriya Jan 2013

Spliceosomal Prp24 Unwinds A Minimal U2/U6 Complex From Yeast, Chandani Manoja Warnasooriya

Wayne State University Theses

Splicing plays a major role in eukaryotic gene expression by processing pre-mRNA to form mature mRNA. Pre-mRNAs undergo splicing to remove introns, non–protein coding regions, and religate exons, protein coding regions. This process is catalyzed by the spliceosome, which consists of five small nuclear ribonucleoprotein particles (snRNPs: U1, U2, U4, U5 and U6) and numerous protein factors. Proper assembly of spliceosomal components is critical for function, and thus, defects in assembly can be lethal. Several spliceosomal proteins facilitate structural rearrangements important for spliceosomal assembly and function. Prp24 is an essential factor in U6 snRNP assembly, and it has been proposed …


Development, Evaluation And Application Of Cyclofructans As Separation Agents, Nilusha L.T Padivitage Jan 2013

Development, Evaluation And Application Of Cyclofructans As Separation Agents, Nilusha L.T Padivitage

Chemistry & Biochemistry Dissertations - Archive

Hydrophilic interaction chromatography (HILIC) is now considered as a viable and established analytical tool for the separation of very polar and hydrophilic compounds, which are not sufficiently retained under Reversed phase liquid chromatography (RPLC). HILIC is becoming a routine technique in the areas of proteomic and metabolomic research and it is steadily increasing in importance in the fields of pharmaceutical, biolological, environmental and food chemistry. HILIC shows a complementary selectivity to RPLC. The use of water-miscible organic rich mobile phases (generally a mixture of acetonitrile and water (1-40 % of water in the mobile phase) is compatible with atmospheric pressure …


Anion Detection In The Positive Ion Mode Electrospray Ionization Mass Spectrometry By Use Of Cationic Ion Pairing Agents: Behavior And Applications, Edra Dodbiba Jan 2013

Anion Detection In The Positive Ion Mode Electrospray Ionization Mass Spectrometry By Use Of Cationic Ion Pairing Agents: Behavior And Applications, Edra Dodbiba

Chemistry & Biochemistry Dissertations - Archive

Anion detection and quantitation has long been of great interest to many scientific areas of research in academic and industrial settings. Their importance extends to areas such as water and environmental analysis, biological system analysis, and also the pharmaceutical and food industries. A variety of sensitive detection methods have been developed for anions. Many of these methods have significant advantages, but also drawbacks. In my dissertation I have described a new method for the detection of anions using electrospray ionization mass spectrometry (ESI-MS) positive ion mode, and cationic ion pairing reagents. Using this method, anions are paired with a plethora …


Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis Jan 2013

Spectroscopic Analysis Of Polymerization And Exonuclease Proofreading By A High-Fidelity Dna Polymerase During Translesion Dna Synthesis, Babho Devadoss, Irene Lee, Anthony J. Berdis

Chemistry Faculty Publications

High fidelity DNA polymerases maintain genomic fidelity through a series of kinetic steps that include nucleotide binding, conformational changes, phosphoryl transfer, polymerase translocation, and nucleotide excision. Developing a comprehensive understanding of how these steps are coordinated during correct and pro-mutagenic DNA synthesis has been hindered due to lack of spectroscopic nucleotides that function as efficient polymerase substrates. This report describes the application of a non-natural nucleotide designated 5-naphthyl-indole-2′-deoxyribose triphosphate which behaves as a fluorogenic substrate to monitor nucleotide incorporation and excision during the replication of normal DNA versus two distinct DNA lesions (cyclobutane thymine dimer and an abasic site). Transient …


An Acid Catalyzed Reversible Ring-Opening/Ring-Closure Reaction Involving A Cyano-Rhodamine Spirolactam, H. Li, H. Guan, X. Duan, J. Hu, Guiren Wang, Qian Wang Jan 2013

An Acid Catalyzed Reversible Ring-Opening/Ring-Closure Reaction Involving A Cyano-Rhodamine Spirolactam, H. Li, H. Guan, X. Duan, J. Hu, Guiren Wang, Qian Wang

Faculty Publications

Cyanamide was introduced into the rhodamine spirolactam framework to produce a colorless and non-fluorescent compound RBCN. It shows a reversible ring-opening/ring-closure process in response to the solution pH, which exhibits an “ON/OFF” switching in its fluorescence. Different from other rhodamine-type dyes, the ring-open form of RBCN is stable in protic solvents under neutral, near neutral and basic conditions, showing a pink color and very strong fluorescence. We also demonstrated the potential of RBCN in live cell imaging.


Production Mechanisms, Number Concentration, Size Distribution, Chemical Composition, And Optical Properties Of Sea Spray Aerosols, Nicholas Meskhidze, Markus D. Petters, Kostas Tsigaridis, Tim Bates, Colin O'Dowd, Jeff Reid, Ernie R. Lewis, Brett Gantt, Magdalena D. Anguelova, Prakash V. Bhave, Andrew Wozniak Jan 2013

Production Mechanisms, Number Concentration, Size Distribution, Chemical Composition, And Optical Properties Of Sea Spray Aerosols, Nicholas Meskhidze, Markus D. Petters, Kostas Tsigaridis, Tim Bates, Colin O'Dowd, Jeff Reid, Ernie R. Lewis, Brett Gantt, Magdalena D. Anguelova, Prakash V. Bhave, Andrew Wozniak

Chemistry & Biochemistry Faculty Publications

(First paragraph)

The impact of sea spray aerosols on global climate remains one of the most uncertain components of the aerosol–radiation–climate problem, but has received less attention than the impacts of terrestrial and anthropogenic aerosols. The last decade has produced a large body of information regarding the sources and composition of marine aerosols, resulting in a reassessment of the complex role that sea spray particles play in climate and various geophysical phenomena. As sea spray aerosol contributes substantially to the preindustrial, natural background which provides the baseline on top of which anthropogenic forcing should be quantified, and because the ocean …


Ultrasensitive Analysis Of Binding Affinity Of Hiv Receptor And Neutralizing Antibodies Using Solution-Phase Electrochemiluminescence Assay, Xiao-Hong Nancy Xu, Zhaoyang Wen, William J. Brownlow Jan 2013

Ultrasensitive Analysis Of Binding Affinity Of Hiv Receptor And Neutralizing Antibodies Using Solution-Phase Electrochemiluminescence Assay, Xiao-Hong Nancy Xu, Zhaoyang Wen, William J. Brownlow

Chemistry & Biochemistry Faculty Publications

Binding of a few ligand molecules with its receptors on cell surface can initiate cellular signaling transduction pathways, and trigger viral infection of host cells. HIV-1 infects host T-cells by binding its viral envelope protein (gp120) with its receptor (a glycoprotein, CD4) on T cells. Primary strategies to prevent and treat HIV infection is to develop therapies (e.g., neutralizing antibodies) that can block specific binding of CD4 with gp120. The infection often leads to the lower counts of CD4 cells, which makes it an effective biomarker to monitor the AIDS progression and treatment. Despite research over decades, quantitative assays for …


Improved Method For Quantifying The Air-Sea Flux Of Volatile And Semi-Volatile Organic Carbon, Emily Hauser, Rebecca M. Dickhut, Renee Falconer, Andrew S. Wozniak Jan 2013

Improved Method For Quantifying The Air-Sea Flux Of Volatile And Semi-Volatile Organic Carbon, Emily Hauser, Rebecca M. Dickhut, Renee Falconer, Andrew S. Wozniak

Chemistry & Biochemistry Faculty Publications

A method for quantifying the diffusive air-sea exchange of gaseous organic carbon (OC) was developed. OC compounds were separated into two operational pools-those that were kinetically air limited in diffusion across the air-sea interface and those that were water limited-during simultaneous air/water sampling. The method separates OC compounds into low Henry's law constant (low-H) semivolatile OC (SOC) and high Henry's law constant (high-H) volatile OC (VOC) pools that can be categorized by relating diffusion kinetic parameters to Henry's Law constant. Air limited (low-H; H << similar to 0.1 L atm mol(-1)) compounds were collected in pure water traps and were quantified as dissolved OC, whereas …


Silver Nanoparticles Induce Developmental Stage-Specific Embryonic Phenotypes In Zebrafish, Kerry J. Lee, Lauren M. Browning, Prakash D. Nallathamby, Christopher J. Osgood, Xiao-Hong Nancy Xu Jan 2013

Silver Nanoparticles Induce Developmental Stage-Specific Embryonic Phenotypes In Zebrafish, Kerry J. Lee, Lauren M. Browning, Prakash D. Nallathamby, Christopher J. Osgood, Xiao-Hong Nancy Xu

Chemistry & Biochemistry Faculty Publications

Much is anticipated from the development and deployment of nanomaterials in biological organisms, but concerns remain regarding their biocompatibility and target specificity. Here we report our study of the transport, biocompatibility and toxicity of purified and stable silver nanoparticles (Ag NPs, 13.1 ± 2.5 nm in diameter) upon the specific developmental stages of zebrafish embryos using single NP plasmonic spectroscopy. We find that single Ag NPs passively diffuse into five different developmental stages of embryos (cleavage, early-gastrula, early-segmentation, late-segmentation, and hatching stages), showing stage-independent diffusion modes and diffusion coefficients. Notably, the Ag NPs induce distinctive stage and dose-dependent phenotypes and …


A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper Jan 2013

A Preliminary Examination Of An In Situ Dual Dye Approach To Measuring Light Fluxes In Lotic Systems, Elizabeth C. Minor, Elizabeth James, Jay A. Austin, Veronica Nelson, Ryan Lusk, Kenneth Mopper

Chemistry & Biochemistry Faculty Publications

Light is a critical parameter in aquatic ecosystems, affecting primary production and in situ photochemistry. However, measuring light exposure for suspended particles or dissolved components in a dynamic water column can be challenging with existing Eulerian approaches. Here, we assess the simultaneous deployment of two dyes differing in photolability (rhodamine WT and fluorescein) as a Lagrangian measure of sunlight exposure in a lotic system. Fluorescein is sensitive to light exposure; rhodamine WT is relatively photostable. We examined dye fluorescence at various pH, salinity, and temperature conditions. We also tested dye photolability as a function of pH and wavelength range. In …


An Expanded Genetic Code In Mammalian Cells With A Functional Quadruplet Codon, Wei Niu, Peter G. Schultz, Jiantao Guo Jan 2013

An Expanded Genetic Code In Mammalian Cells With A Functional Quadruplet Codon, Wei Niu, Peter G. Schultz, Jiantao Guo

Department of Chemistry: Faculty Publications

We have utilized in vitro evolution to identify tRNA variants with significantly enhanced activity for the incorporation of unnatural amino acids into proteins in response to a quadruplet codon in both bacterial and mammalian cells. This approach will facilitate the creation of an optimized and standardized system for the genetic incorporation of unnatural amino acids using quadruplet codons, which will allow the biosynthesis of biopolymers that contain multiple unnatural building blocks.