Relevant bibliographies by topics / Amide resonance

Academic literature on the topic 'Amide resonance'

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Published: 10 December 2022
Last updated: 29 January 2023

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Journal articles on the topic "Amide resonance"

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Albatany, Mohammed, Susan Meakin, and Robert Bartha. "Brain pH Measurement Using AACID CEST MRI Incorporating the 2 ppm Amine Resonance." Tomography 8, no. 2 (March 9, 2022): 730–39. http://dx.doi.org/10.3390/tomography8020060.

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Many pathological conditions lead to altered intracellular pH (pHi) disrupting normal cellular functions. The chemical exchange saturation transfer (CEST) method, known as Amine and Amide Concentration Independent Detection (AACID), can produce image contrast that is predominantly dependent on tissue intracellular pHi. The AACID value is linearly related to the ratio of the 3.5 ppm amide CEST effect and the 2.75 ppm amine CEST effect in the physiological range. However, the amine CEST effect at 2 ppm is often more clearly defined in vivo, and may provide greater sensitivity to pH changes. The purpose of the current study was to compare AACID measurement precision utilizing the 2.0 and 2.75 ppm amine CEST effects. We hypothesized that the 2.0 ppm amine CEST resonance would produce measurements with greater sensitivity to pH changes. In the current study, we compare the range of the AACID values obtained in 24 mice with brain tumors and in normal tissue using the 2 ppm and 2.75 ppm amine resonances. All CEST data were acquired on a 9.4T MRI scanner. The AACID measurement range increased by 39% when using the 2 ppm amine resonance compared to the 2.75 ppm resonance, with decreased measurement variability across the brain. These data indicate that in vivo pH measurements made using AACID CEST can be enhanced by incorporating the 2 ppm amine resonance. This approach should be considered for pH measurements made over short intervals when no changes are expected in the concentration of metabolites that contribute to the 2 ppm amine resonance.
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Piontek, Aleksandra, Elwira Bisz, Błażej Dziuk, Roman Szostak, and Michal Szostak. "Structures and energetic properties of 4-halobenzamides." Acta Crystallographica Section C Structural Chemistry 74, no. 11 (October 23, 2018): 1395–402. http://dx.doi.org/10.1107/s2053229618013463.

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The amide bond represents one of the most fundamental functional groups in chemistry. The properties of amides are defined by amidic resonance (nN→π*C=O conjugation), which enforces planarity of the six atoms comprising the amide bond. Despite the importance of 4-halo-substituted benzamides in organic synthesis, molecular interactions and medicinal chemistry, the effect of 4-halo-substitution on the properties of the amide bond in N,N-disubstituted benzamides has not been studied. Herein, we report the crystal structures and energetic properties of a full series of 4-halobenzamides. The structures of four 4-halobenzamides (halo = iodo, bromo, chloro and fluoro) in the N-morpholinyl series have been determined, namely 4-[(4-halophenyl)carbonyl]morpholine, C11H12 XNO2, for halo = iodo (X = I), bromo (X = Br), chloro (X = Cl) and fluoro (X = F). Computations have been used to determine the effect of halogen substitution on the structures and resonance energies. 4-Iodo-N-morpholinylbenzamide crystallized with a significant distortion of the amide bond (τ + χN = 33°). The present study supports the correlation between the Ar—C(O) axis twist angle and the twist angle of the amide N—C(O) bond. Comparison of resonance energies in synthetically valuable N-morpholinyl and N-piperidinyl amides demonstrates that the O atom of the morpholinyl ring has a negligible effect on amidic resonance in the series.
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Glover, Stephen A., Adam A. Rosser, and Robert M. Spence. "Studies of the Structure, Amidicity, and Reactivity of N-Chlorohydroxamic Esters and N-Chloro-β,β-dialkylhydrazides: Anomeric Amides with Low Resonance Energies." Australian Journal of Chemistry 67, no. 9 (2014): 1344. http://dx.doi.org/10.1071/ch14270.

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Density functional calculations have been carried out to determine the properties of the title anomeric amides. At the B3LYP/6-31G(d) level, N-chloro-N-methoxyacetamide 8a is computed to be strongly pyramidal at nitrogen with a long amide bond that is untwisted. N-Chloro-N-dimethylaminoacetamide 9a is completely planar, but its amide bond is still much longer than that in N,N-dimethylacetamide 4. This is a steric, rather than a resonance, effect. COSNAR and a trans-amidation method calculate low resonance energies for both model amides, which is attributed to the combined electronegativity of the heteroatoms at the amide nitrogen and the strong anomeric effect when there is a chlorine substituent on nitrogen. When M06 and ωB97X-D dispersion-corrected density functional methods are used with the expanded 6-311++G(d,p) basis set, the resonance energies of 8a (–34 kJ mol–1) and 9a (–49 kJ mol–1) are in line with the gross electronegativity of the substituent atoms. Unlike other anomeric amides, 8a and 9a are not predicted to undergo HERON reactivity.
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Glover, Stephen, and Adam Rosser. "Heteroatom Substitution at Amide Nitrogen—Resonance Reduction and HERON Reactions of Anomeric Amides." Molecules 23, no. 11 (October 31, 2018): 2834. http://dx.doi.org/10.3390/molecules23112834.

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This review describes how resonance in amides is greatly affected upon substitution at nitrogen by two electronegative atoms. Nitrogen becomes strongly pyramidal and resonance stabilisation, evaluated computationally, can be reduced to as little as 50% that of N,N-dimethylacetamide. However, this occurs without significant twisting about the amide bond, which is borne out both experimentally and theoretically. In certain configurations, reduced resonance and pronounced anomeric effects between heteroatom substituents are instrumental in driving the HERON (Heteroatom Rearrangement On Nitrogen) reaction, in which the more electronegative atom migrates from nitrogen to the carbonyl carbon in concert with heterolysis of the amide bond, to generate acyl derivatives and heteroatom-substituted nitrenes. In other cases the anomeric effect facilitates SN1 and SN2 reactivity at the amide nitrogen.
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Zeimaran, Ehsan, Sobhan Bahraeian, Taravat Ghanbari, Sara Pourshahrestani, and Hussin Mohd Nor. "Synthesis and Characterization of Supramolecular Elastomers from Polyacids Composed of Vegetable Oils." Advanced Materials Research 747 (August 2013): 505–8. http://dx.doi.org/10.4028/www.scientific.net/amr.747.505.

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Supramolecular elastomers were synthesized using vegetable oil materials namely palm acid oil (PAO) and sunflower oil (SFO). The oils were first epoxidized using formic acid and hydrogen peroxide. The epoxidized oils and adipic acid were then reacted to make polyacids, mainly triacid. Finally, diethylenetriamine (DETA) was added to polyacid to yield fatty amide and a polycondensation with urea performed to achieve the desired elastomers. The synthesized materials were characterized by using Fourier Transform Infrared (FTIR), Nuclear Magnetic Resonance (NMR) and Thermogravimetric Analyzer (TGA) in order to determine structure, type of bonding and thermal stability. The spectrums revealed that the synthesized fatty amides are contained amide groups that correctly formed from reaction of amine groups of DETA and acid functionality of polyacids. Moreover, the resulted structures showed the formation of multiple hydrogen-bonding in the elastomers. TGA thermograms clearly indicated good thermal stability of the elastomers to 500 °C.
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Nagae, Haruki, Takahiro Hirai, Daiki Kato, Shusei Soma, Shin-ya Akebi, and Kazushi Mashima. "Dinuclear manganese alkoxide complexes as catalysts for C–N bond cleavage of simple tertiary N,N-dialkylamides to give esters." Chemical Science 10, no. 10 (2019): 2860–68. http://dx.doi.org/10.1039/c8sc05819a.

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Amide bonds are stable due to the resonance between the nitrogen lone pair and the carbonyl moiety, and therefore the chemical transformation of amides, especially tertiary amides, involving C–N bond fission is considered one of the most difficult organic reactions, unavoidably requiring harsh reaction conditions and strong acids or bases.
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McVicar, Nevin, Alex X. Li, Daniela F. Gonçalves, Miranda Bellyou, Susan O. Meakin, Marco AM Prado, and Robert Bartha. "Quantitative Tissue Ph Measurement during Cerebral Ischemia Using Amine and Amide Concentration-Independent Detection (AACID) with MRI." Journal of Cerebral Blood Flow & Metabolism 34, no. 4 (February 5, 2014): 690–98. http://dx.doi.org/10.1038/jcbfm.2014.12.

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Tissue pH is an indicator of altered cellular metabolism in diseases including stroke and cancer. Ischemic tissue often becomes acidic due to increased anaerobic respiration leading to irreversible cellular damage. Chemical exchange saturation transfer (CEST) effects can be used to generate pH-weighted magnetic resonance imaging (MRI) contrast, which has been used to delineate the ischemic penumbra after ischemic stroke. In the current study, a novel MRI ratiometric technique is presented to measure absolute pH using the ratio of CEST-mediated contrast from amine and amide protons: amine/amide concentration-independent detection (AACID). Effects of CEST were observed at 2.75 parts per million (p.p.m.) for amine protons and at 3.50 p.p.m. for amide protons downfield (i.e., higher frequency) from bulk water. Using numerical simulations and in vitro MRI experiments, we showed that pH measured using AACID was independent of tissue relaxation time constants, macromolecular magnetization transfer effects, protein concentration, and temperature within the physiologic range. After in vivo pH calibration using phosphorus (31P) magnetic resonance spectroscopy (31P-MRS), local acidosis is detected in mouse brain after focal permanent middle cerebral artery occlusion. In summary, our results suggest that AACID represents a noninvasive method to directly measure the spatial distribution of absolute pH in vivo using CEST MRI.
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Katagiri, Gen, James D. Leonard, and Terry L. Gustafson. "Ultraviolet Resonance Raman Study of Nylon-6." Applied Spectroscopy 49, no. 6 (June 1995): 773–79. http://dx.doi.org/10.1366/0003702953964507.

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Ultraviolet resonance Raman spectra of nylon-6 have been investigated with the use of a quasi-continuous UV excitation source based on cw mode-locked Nd:YAG and Nd:YLF lasers. The selective enhancement of the amide vibrational modes is discussed in relation to the reported results for simple amide compounds and polypeptides in aqueous solution. The ultraviolet excitation can extract the amide III mode at 1280 cm−1 for the first time, from significantly overlapped CH2 vibrational modes. The UV-enhanced mode is observed at 1380 cm−1 and is attributed to the controversial amide S mode. We also demonstrate the utility of the present quasi-continuous laser system as an excellent UV source for ultraviolet resonance Raman studies of solid materials.
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Bernhardt, Paul V., and Curt Wentrup. "Structures of 4-Iminopyrido[1,2-a]pyrimidines, Pyrido[1,2-a]pyrimidin-4-ones, Pyridopyrimidinium Olates, and Thiazolo[3,2-a]pyrimidine Analogues." Australian Journal of Chemistry 65, no. 4 (2012): 371. http://dx.doi.org/10.1071/ch12040.

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The Structure-Correlation Principle of Bürgi and Dunitz is invoked in an analysis of the structures of 2-chloro-8-methyl-4-(2-(4-picolinyl)imino-4H-pyrido[1,2-a]pyrimidine 8, 7-chloro-5-(2-thiazolyl)imino-5H-thiazolo[3,2-a]pyrimidine 9, 2-methylamino-4H-pyrido[1,2-a]pyrimidin-4-one 10, 7-methylthio-5H-thiazolo[3,2-a]pyrimidin-5-one 11, 2,3-dihydro-7-methylthio-5H-thiazolo[3,2-a]pyrimidin-5-one 12, and 1-methyl-2-[(o-tert-butylphenyl)imino]-1,2-dihydropyrido[1,2-a]pyrimidin-1-ium-4-olate 13, which have been determined by X-ray crystallography. The most notable structural peculiarities are the long ‘amidine’ and ‘amide’ C–N bonds (1.40–1.50 Å) and the tilting of the ‘amidine’ C=N and ‘amide’ C=O groups towards a ring nitrogen atom (NCX = 114–118°). Also the ‘amidine’ C=N (1.28 Å) and ‘amide’ C=O bonds (1.22–1.24 Å) are long, i.e. in the normal range for resonance-stabilized amidines and amides in spite of the lack of such resonance in these compounds. These features mimic the transition states for ring opening to ketenes. The long amidine and amide C–N bonds and acute NCX angles are in accord with the observed thermal ring opening to ketenimines and ketenes, respectively.
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Glover, Stephen A., and Adam A. Rosser. "The role of substituents in the HERON reaction of anomeric amides." Canadian Journal of Chemistry 94, no. 12 (December 2016): 1169–80. http://dx.doi.org/10.1139/cjc-2016-0300.

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Anomeric amides, RCON(X)(Y), have two electronegative atoms at the amide nitrogen, a configuration that results in greatly reduced amide resonance and strongly pyramidal nitrogen atoms. This, combined with facilitation of anomeric interactions, can result in the HERON reaction, an intramolecular migration of the more electronegative atom, X, from nitrogen to the carbonyl with production of a Y-stabilised nitrene. We have modelled, at the B3LYP/6-31G(d) level, a variety of anomeric amides that undergo the HERON reaction to determine factors that underpin the process. The overriding driving force is anomeric destabilisation of the bond to the migrating group. Rotated transition states show loss of residual resonance and this is a component of the overall activation energies. However, the reduced resonance in these systems plays only a minor role. We have determined the resonance energies (RE) and HERON activation barriers (EA) of five anomeric systems. REs for the amides have been calculated isodesmically using our calibrated trans amidation method and COSNAR calculations. Reduction of their overall EAs by the corresponding RE gives rearrangement energies (Erearr.), a measure of relative impact on rearrangement of substituents on nitrogen. In CH3CON(OMe)(Y) systems producing (CH3CO2Me + NY), a loosely bound electron pair on the donor atom, Y, in nY–σ*NOMe anomeric interactions drives the reaction. Erearr. increases in the sequence Y = N(nitrene) < O−(oxide) ≪ NMe2 < SMe ≪ OMe. For the same systems, RE increases in the order Y = N < O− ≪ OMe ≪ NMe2 ∼ SMe. Other effects such as molecular conformation, nature of the migrating group, X, and acyl substituents at the carbonyl carbon are discussed.
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Dissertations / Theses on the topic "Amide resonance"

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Gaul, David Allen. "Synthetic, mechanistic, structural, and dynamic NMR investigations of zinc bis(amide) compounds." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/30741.

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Sakata, Akihiko. "Grading glial tumors with amide proton transfer MR imaging: different analytical approaches." Kyoto University, 2016. http://hdl.handle.net/2433/215431.

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Final publication is available at http://link.springer.com/article/10.1007/s11060-014-1715-8
Kyoto University (京都大学)
0048
新制・課程博士
博士(医学)
甲第19605号
医博第4112号
新制||医||1014(附属図書館)
32641
京都大学大学院医学研究科医学専攻
(主査)教授 村井 俊哉, 教授 平岡 眞寛, 教授 山田 泰広
学位規則第4条第1項該当
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Tse, Man-kit. "Structural characterization and domain dissection of human XAF1 protein, and application of solvent-exposed-amide spectroscopy in mapping protein-protein interface." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43223801.

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Tse, Man-kit, and 謝汶桀. "Structural characterization and domain dissection of human XAF1 protein, and application of solvent-exposed-amide spectroscopy inmapping protein-protein interface." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43223801.

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Xu, Chao [Verfasser]. "Exploring novel magnetic resonance imaging markers for ischemic stroke in the application of vessel size imaging and amide proton transfer imaging / Chao Xu." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2012. http://d-nb.info/1028494939/34.

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Yu, Xue, and 于雪. "Imaging of peritoneal metastasis : evaluation of diagnostic performance of DWI-MRI and FDG-PET/CT, correlation of the functional indices and feasibility study based on amide proton transfer MRI." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2013. http://hdl.handle.net/10722/193483.

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Introduction Peritoneal metastasis is advanced disease and is usually widely disseminated at the time of discovery. It is crucial to detect peritoneal metastasis at an early stage and to allow precise patient selection for the right treatments. Both fluorodeoxyglucose positron emission tomography/computed tomography (FDGPET/CT) and magnetic resonance imaging (MRI) are used in peritoneal metastasis detection. Standardized uptake value (SUV), derived from FDGPET/ CT can evaluate glucose metabolism in cells, whilst apparent diffusion coefficient (ADC) derived from diffusion-weighted MRI (DWI) is used for quantitative analysis of tumour cellularity. Amide proton transfer (APT) MRI is a novel imaging technique based on exchangeable amide protons as endogenous contrast agent and can measure the increased amide proton signal in malignant tissues indirectly through bulk water proton signals. This thesis aims to: 1) compare the diagnostic performance of FDG-PET/CT and MRI in peritoneal metastasis evaluation; 2) study the relationship between SUV and ADC in peritoneal metastasis; 3) investigate the feasibility of APT in peritoneal metastasis evaluation. Materials and Methods Patients with peritoneal metastasis detected on FDG-PET/CT were prospectively recruited for MRI. FDG-PET/CT and MRI images were reviewed independently by two radiologists in separate sessions. Diagnostic characteristics were calculated for both imaging techniques. SUVmax and SUVmean were obtained by placing ROIs on PET, while ADCmin and ADCmean were calculated by contouring lesions on DWI. APT MRI was performed using a single-slice turbo spin echo sequence, with a block of presaturation pulses at 33 frequency offsets. ROIs were placed on peritoneal metastasis and muscle on APT. Mean of integrated asymmetrical magnetic transfer ratio (MTRasym) over 3-4 ppm with respect to water resonance was calculated for peritoneal metastasis and muscle. Results Eight patients were recruited in this study with 128 anatomical sites evaluated. DWI/MRI had good diagnostic performance (sensitivity = 92%, specificity = 99%, accuracy = 98%) compared to that of FDG-PET/CT (sensitivity = 90%, specificity= 100%, accuracy = 98%). Thirty-four peritoneal metastases were selected for quantitative analysis. Significant inverse correlation was found between ADCmean and SUVmax (r = -0.528, p = 0.001) and between ADCmean and SUVmean (r = -0.548, p = 0.001). ADCmin was significantly and negatively correlated with SUVmax (r = -0.508, p = 0.002) and SUVmean (r = -0.513, p = 0.002). In the above study cohort, 6 patients underwent APT imaging with 8 peritoneal metastases evaluated. Seven lesions showed positive APT signal and one had negative APT signal. The mean APT signal for peritoneal metastasis was 2.28%±1.76%, significantly different from that of muscle (-2.79%±0.95%, p < 0.001). Conclusions In conclusion, both DWI/MRI and FDG-PET/CT had good diagnostic performance in peritoneal metastasis evaluation. The negative correlation between SUV and ADC suggested an inverse relationship between tissue metabolism and cellularity. APT MRI is feasible to generate sufficient contrast signal for peritoneal metastasis and has potential to discriminate peritoneal tumours from its surrounding soft tissue using integrated MTRasym as a quantitative marker. These functional indices allow understanding of the biological behaviours of peritoneal tumours and could act as adjuncts in peritoneal metastasis imaging.
published_or_final_version
Diagnostic Radiology
Master
Master of Philosophy
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Tee, Yee Kai. "Quantitative measurement of pH in stroke using chemical exchange saturation transfer magnetic resonance imaging." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:e5634676-55a5-43ef-92e7-12166f3d6bf0.

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Stroke is one of the leading causes of death and adult disability worldwide. The major therapeutic intervention for acute ischemic stroke is the administration of recombinant tissue plasminogen activator (rtPA) to help to restore blood flow to the brain. This has been shown to increase the survival rate and to reduce the disability of ischemic stroke patients. However, rtPA is associated with intracranial haemorrhage and thus its administration is currently limited to only about 5% of ischemic stroke patients. More advanced imaging techniques can be used to better stratify patients for rtPA treatment. One new imaging technique, chemical exchange saturation transfer (CEST) magnetic resonance imaging, can potentially image intracellular pH and since tissue acidification happens prior to cerebral infarction, CEST has the potential to predict ischemic injury and hence to improve patient selection. Despite this potential, most studies have generated pH-weighted rather than quantitative pH maps; the most widely used metric to quantify the CEST effect is only able to generate qualitative contrast measurements and suffers from many confounds. The greatest clinical benefit of CEST imaging lies in its ability to non-invasively measure quantitative pH values which may be useful to identify salvageable tissue. The quantitative techniques and work presented in this thesis thus provide the necessary analysis to determine whether a threshold for the quantified CEST effect or for pH exists to help to define tissue outcome following stroke; to investigate the potential of CEST for clinical stroke imaging; and subsequently to facilitate clinical translation of CEST for acute stroke management.
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Msayib, Yunus. "Quantifying impaired metabolism following acute ischaemic stroke using chemical exchange saturation transfer magnetic resonance imaging." Thesis, University of Oxford, 2017. http://ora.ox.ac.uk/objects/uuid:a98323ce-5998-436d-bca4-09df549cf191.

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In ischaemic stroke a disruption of cerebral blood flow leads to impaired metabolism and the formation of an ischaemic penumbra in which tissue at risk of infarction is sought for clinical intervention. In stroke trials, therapeutic intervention has largely been based on perfusion-weighted measures, but these have not been shown to be good predictors of tissue outcome. The aim of this thesis was to develop analysis techniques for magnetic resonance imaging (MRI) of chemical exchange saturation transfer (CEST) in order to quantify metabolic signals associated with tissue fate in patients with acute ischaemic stroke. This included addressing robustness for clinical application, and developing quantitative tools that allow exploration of the in-vivo complexity. Tissue-level analyses were performed on a dataset of 12 patients who had been admitted to the John Radcliffe Hospital in Oxford with acute ischaemic stroke and recruited into a clinical imaging study. Further characterisation of signals was performed on stroke models and tissue phantoms. A comparative study of CEST analysis techniques established a model-based approach, Bloch-McConnell model analysis, as the most robust for measuring pH-weighted signals in a clinical setting. Repeatability was improved by isolating non-CEST effects which attenuate signals of interest. The Bloch-McConnell model was developed further to explore whether more biologically-precise quantification of CEST effects was both possible and necessary. The additional model complexity, whilst more reflective of tissue biology, diminished contrast that distinguishes tissue fate, implying the biology is more complex than pH alone. The same model complexity could be used reveal signal patterns associated with tissue outcome that were otherwise obscured by competing CEST processes when observed through simpler models. Improved quantification techniques were demonstrated which were sufficiently robust to be used on clinical data, but also provided insight into the different biological processes at work in ischaemic tissue in the early stages of the disease. The complex array of competing processes in pathological tissue has underscored a need for analysis tools adequate for investigating these effects in the context of human imaging. The trends herein identified at the tissue level support the use of quantitative CEST MRI analysis as a clinical metabolic imaging tool in the investigation of ischaemic stroke.
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Galius, Veniamin. "Automated assignment of amide resonances in NMR spectra of proteins with known crystal structure /." [S.l.] : [s.n.], 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=18043.

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Green, Edward L. "Characterization of the TPQ cofactor in amine oxidases and the heme cofactor in cystathionine beta-synthase by resonance raman spectroscopy. : Implications for catalytic properties /." Full text open access at:, 2001. http://content.ohsu.edu/u?/etd,224.

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Books on the topic "Amide resonance"

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Brownlee, Victoria. A Tale of Two Jobs. Oxford University Press, 2018. http://dx.doi.org/10.1093/oso/9780198812487.003.0004.

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Chapter 3 addresses the Old Testament figure of Job. It considers the resonance of his biblical narrative amid a climate of religious persecution in Europe. Job’s narrative was typically understood to mark bodily suffering as a test of faith and, for many readers, affirmed that their suffering, like Job’s, was divinely authorized for a finite period of time. A wave of theological and literary writings affirm the remarkable impact of the Joban trajectory of suffering in early modern culture. Shakespeare’s King Lear is no exception. Yet, instead of upholding the Joban paradigm of eventual restoration—a feature of the anonymous source play, King Leir—Shakespeare’s play is notable for its deliberate disruption of the typological process of promise and fulfilment. In fact, this play offers a shocking inversion of established exegetical traditions of suffering more generally.
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Bussel, Robert. Epilogue. University of Illinois Press, 2017. http://dx.doi.org/10.5406/illinois/9780252039492.003.0013.

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This epilogue reflects on the legacy of Harold Gibbons and Ernest Calloway. It begins with a discussion of some valuable insights that the two men's experience provides. As far back as the 1960s, Gibbons and Calloway lamented the stagnation of union organizing amid structural changes in the economy that were diluting labor's strength. They thought creatively about how the Teamsters could exercise decisive economic leverage, and their concept of treating workers as total persons might find new political resonance in tackling the work–family divide that has arisen as dual earner families have become a social norm. The epilogue also considers several sobering aspects of Gibbons and Calloway's careers, including the short-lived successes of total person unionism as well as its limited reach, both within St. Louis and elsewhere. Finally, it suggests that Gibbons and Calloway's most powerful legacy was their insistence on the essential interrelationships between work, citizenship, and democracy.
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Book chapters on the topic "Amide resonance"

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Vaithilingam, Krishnakumar, and Sameer Mahmood Zaheer. "Optimization and Validation of Amine Coupling of Ligand." In Methods for Fragments Screening Using Surface Plasmon Resonance, 69–76. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-1536-8_9.

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Thiagaraj, Dinesh, and Ponni Vijayan. "Preparation of Protein with Histidine Tag for Amine Coupling." In Methods for Fragments Screening Using Surface Plasmon Resonance, 11–21. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-1536-8_3.

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Kręglewski, Marek. "Vibration - Inversion - Torsion - Rotation Energy Levels and Vibrational Resonances in the Methyl Amine Molecule." In Structures and Conformations of Non-Rigid Molecules, 29–43. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-011-2074-6_2.

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WAGNER, GERHARD, and KURT WÜTHRICH. "Amide Proton Exchange and Surface Conformation of the Basic Pancreatic Trypsin Inhibitor in Solution: Studies with Two-dimensional Nuclear Magnetic Resonance." In NMR in Structural Biology, 540–58. WORLD SCIENTIFIC, 1995. http://dx.doi.org/10.1142/9789812795830_0048.

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Zhang, Zhongqi, Weiqun Li, Ming Li, Timothy M. Logan, Shenheng Guan, and Alan G. Marshall. "Higher-order structure and dynamics of FK506-binding protein probed by backbone amide hydrogen/deuterium exchange and electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry." In Techniques in Protein Chemistry, 703–13. Elsevier, 1997. http://dx.doi.org/10.1016/s1080-8914(97)80069-5.

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Cimini, Amy. "Adjacencies and Its Negations." In Wild Sound, 50–103. Oxford University Press, 2022. http://dx.doi.org/10.1093/oso/9780190060893.003.0002.

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“How can worlds of sound be joined?” While Amacher developed this question in realized and unrealized concert music during the mid-1960s, it also conjoined spectral and spatial ways of listening in her inaugural broadcast and environmental projects, City-Links WBFO, Buffalo, and In City, Buffalo 1967 on much different historical and material terrain. A close look at conceptual and notational strategies in Amacher’s electroacoustic percussion work Adjacencies illuminates her musical thought at an early stage and reveals how spectral listening could function as meeting place within which sound and ongoing life exchange intensities elsewhere. Critical comparisons with Karlheinz Stockhausen’s Mikrophonie I (1964) and Anthony Braxton’s Composition No. 9 for Amplified Shoveller Quartet (1969) elaborate how musical forms and experiences amid resonant metals, dramaturgy, and promissory grammar can work in concert or in conflict with historical spaces of biopolitics. Following Adjacencies’ archival traces across the radio broadcast City-Links and festival-like In City moves its connective ways of listening into concrete changes amid so-called redevelopment in urban history and policy debates, entwining social histories and media aesthetics that will inform Amacher’s long-distance projects in the decade to follow.
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DUBS, ANDREAS, GERHARD WAGNER, and KURT WÜTHRICH. "INDIVIDUAL ASSIGNMENTS OF AMIDE PROTON RESONANCES IN THE PROTON NMR SPECTRUM OF THE BASIC PANCREATIC TRYPSIN INHIBITOR." In NMR in Structural Biology, 62–79. WORLD SCIENTIFIC, 1995. http://dx.doi.org/10.1142/9789812795830_0006.

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Mark, James E., Dale W. Schaefer, and Gui Lin. "Copolymers and Interpenetrating Networks." In The Polysiloxanes. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780195181739.003.0010.

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Random copolymers are prepared by the copolymerization of a mixture of cyclic oligomers. Although the resulting polymer can be quite blocky (figure 8.1), taking the reaction to equilibrium can give a polymer that is essentially random in its chemical sequencing. One reason for preparing copolymers is to introduce functional species, such as hydrogen or vinyl side groups, along the chain backbone to facilitate cross linking. Another reason is the introduction of sufficient chain irregularity to make the polymer inherently noncrystallizable. Specific examples of comonomers include imides, perylenediimide, urethane-ureas, epoxies, other siloxanes, amides, styrene, divinylbenzene, acrylics, silsesquioxanes, polythiophenes, and poly(lactic acid). One novel combination is the preparation of polysiloxanebased episulfide resins. An unusual application is the use of monomethylitaconate- grafted polymethylsiloxane to induce crystal growth of CaCO3. Polysiloxanes containing thermally curable brenzoxazine moieties in the main chain are also in the category. These and other copolymers have been extensively characterized by nuclear magnetic resonance (NMR) spectroscopy. The sequential coupling of functionally terminated chains of different chemical structure can be used to make block copolymers, including those in which one or more of the blocks is a polysiloxane. If the blocks are relatively long, separation into a two-phase system invariably occurs. Frequently, one block will be in a continuous phase and the other will be dispersed in domains having an average size the order of a few hundred angstroms. Such materials can have unique mechanical properties not available from homopolymer species. Sometimes similar properties can be obtained by the simple blending of two or more polymers. Examples of blocks used with polydimethylsiloxane (PDMS) include imides, epoxies, butadienes, ε-caprolactones, amides having trichlorogermyl pendant groups, urethanes, ureas, poly(ethylene glycols), polystyrene, vinyl acetates, acrylates or methacrylates, 2-vinylpyridine, and even other polysiloxanes. Some results have also been reported for polyesters, polyethers, hydroxyethers of bisphenol A, bisphenol A arylene ether sulfones, vinylpyridinebenzoxazines, methyloxazolines, terpyridines, polysulfones, &gamma;-benzyl-Lglutamate, and carboranes. Two other examples are foamed polypropylene and melamine resins. Even ABA, ABC triblock copolymers, and ABCBA pentablock copolymers involving PDMS have been reported.
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Markham, Michael. "Bach Anxiety." In Rethinking Bach, 337–60. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780190943899.003.0015.

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A recent Twitter post by the composer Nico Muhly aligns with a recurring trope of “Bach-ness” that defines Bach’s public mythic profile. This chapter focuses on similar images of Bach, whether visual or aural. Bach has been most commonly imagined in the popular consciousness as representing not the human but the superhuman, the inhuman, the dehumanized, and the sublime. One can sense in recent writings on Bach an anxiety about how well these attributes can continue to resonate in our current moment of political or cultural relevance tests, and about which works by Bach are most likely to thrive in this new postmodern media world. I will wonder aloud, with some trepidation, whether Bach’s public mythic profile, long solidified along Modernist lines as the encyclopedic mathematical mystic, is undergoing a broad, gradual change; indeed, if it needs to in order for his music to survive in a twenty-first-century media environment and amid a postmodern audience sensibility.
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Drijfhout, Jan W., and Peter Hoogerhout. "Methods of preparing peptide—carrier conjugates." In Fmoc Solid Phase Peptide Synthesis. Oxford University Press, 1999. http://dx.doi.org/10.1093/oso/9780199637256.003.0014.

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For many applications, peptides should be conjugated to carriers. An important example is the conjugation of peptides to proteins, carbohydrates, or lipids for immunological studies. Further examples are the preparation of peptide affinity media and the conjugation of peptides to suitable coating compounds on surfaces for enzyme-linked immunosorbent assay and plasma resonance. The most important consideration in designing conjugates is that the peptide part of the conjugate must retain its biological activity. This means that the site of activity of the peptide must not be involved in the conjugation reaction. However, the active part of the peptide is often not precisely known, which complicates the design of a proper conjugation strategy. In addition, if the peptide is a fragment of a larger biologically active protein, the small peptide will frequently not adopt the conformation (for instance, a loop structure) of the corresponding sequence in the native protein. This might also abolish desired biological properties, such as the possibility to induce functional antibodies recognizing the native protein. In that case, appropriate artificial conformational restrictions should be introduced into the peptide - if possible. From the numerous conjugation methods available, only a few are described in this chapter. One example concerns the application of the homobifunctional cross-linker glutaraldehyde. Heterobifunctional cross-linking is illustrated by coupling of thiol-containing peptides or carriers to sulphydryl-reactive carriers or peptides, respectively. A general and easy method of conjugating peptides to proteins is to make use of homobifunctional cross-linkers. An example of a homobifunctional cross-linker is glutaraldehyde. This bis-aldehyde reacts with amine groups at neutral or basic pH to yield enamines, which can be reduced optionally to amines with sodium cyanoborohydride. The peptide and the protein react selectively via their N-terminus and/or lysine side chains to give not only a very complex mixture of products—peptide-peptide, peptide-protein, and protein-protein conjugates—but also large constructs containing peptide and protein. Typically, several peptide molecules per protein molecule are coupled. In view of the complex reaction pathway, the batch-to-batch reproducibility of the conjugate is difficult to control. If the peptide contains a lysine in the active part, it is recommended to extend the peptide N- or C-terminally with some additional lysines during synthesis in order to provide more amine groups for conjugation.
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Conference papers on the topic "Amide resonance"

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JI, Yan, Xiao-liang YANG, and Jun-ming TANG. "Amide Resonance Structure Detected by NMR to Predict Hydroxyl Unit in Protein." In 2nd International Conference on Biomedical and Biological Engineering 2017 (BBE 2017). Paris, France: Atlantis Press, 2017. http://dx.doi.org/10.2991/bbe-17.2017.74.

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Zhao, Jing, Yinsheng Chen, Yiying Zhao, Shasha Yang, Zhongping Chen, and Yin Wu. "Assessment of chemoradiotherapy response in glioma with magnetic resonance amide proton transfer imaging in a rodent model." In 2017 39th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC). IEEE, 2017. http://dx.doi.org/10.1109/embc.2017.8036881.

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Boogaarts, Maarten G. H., Paul C. Hinnen, Iwan Holleman, Rienk T. Jongma, and Gerard Meijer. "REMPI, SEP and MATI on laser desorbed diphenyl-amine." In The 7th international symposium: Resonance ionization spectroscopy 1994. AIP, 1995. http://dx.doi.org/10.1063/1.47597.

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DASH, JYOTIRMAYEE, Shaumik Ray, Vaibhav Kaware, Nitin Basutkar, Ashootosh V. Ambade, Kavita Joshi, and Bala Pesala. "Terahertz Resonances of Di(pyridin-2-yl)amine: A Detailed Experimental and Computational study." In International Conference on Fibre Optics and Photonics. Washington, D.C.: OSA, 2014. http://dx.doi.org/10.1364/photonics.2014.s5a.79.

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Peng Wu, Jingxin Zhang, Dachao Li, and Kexin Xu. "Optimization of surface plasmon resonance glucose detection based on D-galactose/D-glucose protein amine coupling method." In 2010 OSA-IEEE-COS Advances in Optoelectronics and Micro/Nano-Optics (AOM). IEEE, 2010. http://dx.doi.org/10.1109/aom.2010.5713590.

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Mikael, Luana de Rezende, Coralia Gabrielle Vieira Silveira, Camilla Duarte Ribeiro, Daniel Damiani, Pedro Henrique de Lara Leite, Helton Benevides Santana de Oliveira, Danilo Donizete de Faria, Roberta Arb Saba Rodrigues Pinto, and Sonia Maria Cesar de Azevedo Silva. "Fahr’s syndrome as a differential diagnosis amid parkinsonian syndromes: a case report." In XIII Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1516-3180.465.

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Context: Parkinsonian syndromes are routinely identified by neurologists. However, the differential diagnosis among probable etiologies can be challenging and complex. In Fahr’s syndrome, calcifications of the basal ganglia secondary to disorders of calcium metabolism are observed. A possible clinical presentation associated with this entity is the presence of a parkinsonian syndrome. Case report: A 54-years-old female patient presented with a progressive tremor in the right upper and lower limbs associated with bradykinesia. Seizures were observed during the course of the disease. After extensive clinical workup, primary hypoparathyroidism was diagnosticated along with the recognition of a mutation in the calcium activator gene. Computed tomography and magnetic resonance imaging of the head showed bilateral coarse calcifications in thalami and basal ganglia compatible with Fahr’s syndrome. We began treatment for control of the underlying disease, as well as for symptomatic control of parkinsonism. Conclusions: Different pathologies could justify the parkinsonian syndrome observed initially in the case described. Among them: Iidiopathic Parkinson’s Disease, Multiple System Atrophy, Progressive Supranuclear Palsy. In our patient, the atypical evolution in a young woman led to the research of possible secondary treatable causes. A diagnosis of Fahr’s syndrome related to hypoparathyroidism was unveiled. The differential diagnosis of Parkinson’s Syndrome is broad and difficult. We must be aware of the possible atypical presentations due to the possibility of a secondary condition whose etiology could be effectively treated.
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Wu, Peng, Dachao Li, Jingxin Zhang, Bing Song, and Kexin Xu. "Research on Influencing Factors of Surface Plasmon Resonance Glucose Detection Based on D-Galactose/D-Glucose Protein Immobilizied by Amine Coupling Method." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-40281.

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Prediction of blood glucose based on measuring the glucose concentration in interstitial fluid is an effectively way to control diabetes. A surface plasmon resonance (SPR) system based on a miniature integrated SPR sensor is set up in this paper to measure the glucose concentration in interstitial fluid, and the D-galactose/D-glucose Binding Protein (GGBP) which can specifically absorb glucose is immobilized onto the SPR sensor surface by amine coupling method for higher sensitivity. The experiment result is affected by various factors, such as the grime on sensor surface, baseline, flow velocity, mass transfer effect, temperature, protein activity, bubbles. In this paper these factors are studied systemically by experiments and some solutions are proposed accordingly: (1) Make sure the sensor surface is clean before it is used. (2) Dynamic baseline can provide the best baseline location during the measurement. (3) Flow velocity of 10uL/min-30uL/min is supposed to be chosen. (4) The density of protein immobilized on the sensor surface should maintain lower to avoid the mass transfer effect. (5) Higher response is got when the temperature is between 26°C and 30°C and it is important to keep temperature constant during the experiment. (6) The protein should be preserved with a proper way and make sure it is active during the measurement. (7) The sample should be degassed and filtered before the experiment and make sure there is no air in the pipeline. Through optimizing the experiment conditions, the sensitivity and stability of the measurement are improved.
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Chang, Tsung-Yao, and Chii-Wann Lin. "Solutions of SAT Problems Solved by a SPR-Based DNA Processor." In ASME 2008 First International Conference on Micro/Nanoscale Heat Transfer. ASMEDC, 2008. http://dx.doi.org/10.1115/mnht2008-52036.

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DNA computation has shown its potential not only on mathematics, but on various practical areas such as diagnosis, single nucleotide polymorphism (SNP) detection, smart amplification, encryption and drug delivery etc. However, most previous researches about DNA computation possess a couple of weaknesses, including time-wasting, effort-wasting, lack of reusability and no miniaturization. In order to address this issue and improve weaknesses mentioned above, we built up a surface plasmon resonance (SPR) system for the detection on the DNA array chip to solve a 3-clause satisfiability (SAT) problem with 3 variables x, y and z. Every variable is defined as a 15-nt single strand DNA (ssDNA) which is immobilized on one spot of the gold surface. We further define SPR reflective intensity changes 0, 0.2 and 2 A.U. caused by changes of molecular weight on surface as Boolean signals False, True and None, respectively. Moreover, False signal represents a positive hybridization reaction via the hydrogen bond that binds the complementary ssDNA conjugating to IgG (150 kDa) by the crosslinker Sulfo-SMPB which can links thiol group labeled on ssDNA and amine group existed on IgG; True signal represents the hybridization reaction that binds the complementary ssDNA-IgG-Antigen which can result in a much larger intensity change. For a SAT problem F = (XT ∪ YF)∩(XF ∪ ZT)∩(YT ∪ ZT), there are 8 possible answers. Therefore, we established a 3-spot array as a set which is immobilized sequence x, y and z. After one calculation, we read out the solution of this set and then regenerate it by injecting 0.05 N sodium hydroxide solution. In this work, we used 200 ng/ml Xc-Human IgG, Yc-Rabbit IgG and Zc-Goat IgG as reaction agents for hybridization which represent False signal. Furthermore, 100 ng/ml Anti-Human IgG, Rabbit IgG and Goat IgG were taken as True signal agents. A full reaction can be completed within 30 minutes at room temperature. The buffer in the study is 1 x phosphate buffered solution (PBS) with 100 mM sodium chloride. The proposed platform has improved drawbacks that occurred in previous researches about DNA computer. Besides, it is provided with abilities a processor should have which are recalculable and realtime measurement so that provides us a novel approach for addressable and reusable diagnosis.
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Chen, Kok Hao, and Jong Hyun Choi. "DNA Oligonucleotide-Templated Nanocrystals: Synthesis and Novel Label-Free Protein Detection." In ASME 2009 International Mechanical Engineering Congress and Exposition. ASMEDC, 2009. http://dx.doi.org/10.1115/imece2009-11958.

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Semiconductor and magnetic nanoparticles hold unique optical and magnetic properties, and great promise for bio-imaging and therapeutic applications. As part of their stable synthesis, the nanocrystal surfaces are usually capped by long chain organic moieties such as trioctylphosphine oxide. This capping serves two purposes: it saturates dangling bonds at the exposed crystalline lattice, and it prevents irreversible aggregation by stabilizing the colloid through entropic repulsion. These nanocrystals can be rendered water-soluble by either ligand exchange or overcoating, which hampers their widespread use in biological imaging and biomedical therapeutics. Here, we report a novel scheme of synthesizing fluorescent PbS and magnetic Fe3O4 nanoparticles using DNA oligonucleotides. Our method of PbS synthesis includes addition of Na2S to the mixture solution of DNA sequence and Pb acetate (at a fixed molar ratio of DNA/S2−/Pb2+ of 1:2:4) in a standard TAE buffer at room temperature in the open air. In the case of Fe3O4 particle synthesis, ferric and ferrous chloride were mixed with DNA in DI water at a molar ratio of DNA/Fe2+/Fe3+ = 1:4:8 and the particles were formed via reductive precipitation, induced by increasing pH to ∼11 with addition of ammonium hydroxide. These nanocrystals are highly stable and water-soluble immediately after the synthesis, due to DNA termination. We examined the surface chemistry between oligonucleotides and nanocrystals using FTIR spectroscopy, and found that the different chemical moieties of nucleobases passivate the particle surface. Strong coordination of primary amine and carbonyl groups provides the chemical and colloidal stabilities, leading to high particle yields (Figure 1). The resulting PbS nanocrystals have a distribution of 3–6 nm in diameter, while a broader size distribution is observed with Fe3O4 nanoparticles as shown in Figure 1b and c, respectively. A similar observation was reported with the pH change-induced Fe3O4 particles of a bimodal size distribution where superparamagnetic and ferrimagnetic magnetites co-exist. In spite of the differences, FTIR measurements suggest that the chemical nature of the oligonucleotide stabilization in this case is identical to the PbS system. As a particular application, we demonstrate that aptamer-capped PbS QD can detect a target protein based on selective charge transfer, since the oligonucleotide-templated synthesis can also serve the additional purpose of providing selective binding to a molecular target. Here, we use thrombin and a thrombin-binding aptamer as a model system. These QD have diameters of 3∼6 nm and fluoresce around 1050 nm. We find that a DNA aptamer can passivate near IR fluorescent PbS nanocrystals, rendering them water-soluble and stable against aggregation, and retain the secondary conformation needed to selectively bind to its target, thrombin, as shown in Figure 2. Importantly, we find that when the aptamer-functionalized nanoparticles binds to its target (only the target), there is a highly systematic and selective quenching of the PL, even in high concentrations of interfering proteins as shown in Figure 3a and b. Thrombin is detected within one minute with a detection limit of ∼1 nM. This PL quenching is attributed to charge transfer from functional groups on the protein to the nanocrystals. A charge transfer can suppress optical transition mechanisms as we observe a significant decrease in QD absorption with target addition (Figure 3c). Here, we rule out other possibilities including Forster resonance energy transfer (FRET) and particle aggregation, because thrombin absorb only in the UV, and we did not observe any significant change in the diffusion coefficient of the particles with the target analyte, respectively. The charge transfer-induced photobleaching of QD and carbon nanotubes was observed with amine groups, Ru-based complexes, and azobenzene compounds. This selective detection of an unlabeled protein is distinct from previously reported schemes utilizing electrochemistry, absorption, and FRET. In this scheme, the target detection by a unique, direct PL transduction is observed even in the presence of high background concentrations of interfering negatively or positively charged proteins. This mechanism is the first to selectively modulate the QD PL directly, enabling new types of label free assays and detection schemes. This direct optical transduction is possible due to oligonucleotidetemplated surface passivation and molecular recognition. This chemistry may lead to more nanoparticle-based optical and magnetic probes that can be activated in a highly chemoselective manner.
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Reports on the topic "Amide resonance"

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Fernando, P. U. Ashvin Iresh, Gilbert Kosgei, Matthew Glasscott, Garrett George, Erik Alberts, and Lee Moores. Boronic acid functionalized ferrocene derivatives towards fluoride sensing. Engineer Research and Development Center (U.S.), July 2022. http://dx.doi.org/10.21079/11681/44762.

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In this technical report (TR), a robust, readily synthesized molecule with a ferrocene core appended with one or two boronic acid moieties was designed, synthesized, and used toward F- (free fluoride) detection. Through Lewis acid-base interactions, the boronic acid derivatives are capable of binding with F- in an aqueous solution via ligand exchange reaction and is specific to fluoride ion. Fluoride binding to ferrocene causes significant changes in fluorescence or electrochemical responses that can be monitored with field-portable instrumentation at concentrations below the WHO recommended limit. The F- binding interaction was further monitored via proton nuclear magnetic resonance spectroscopy (1H-NMR). In addition, fluorescent spectroscopy of the boronic acid moiety and electrochemical monitoring of the ferrocene moiety will allow detection and estimation of F- concentration precisely in a solution matrix. The current work shows lower detection limit (LOD) of ~15 μM (285 μg/L) which is below the WHO standards. Preliminary computational calculations showed the boronic acid moieties attached to the ferrocene core interacted with the fluoride ion. Also, the ionization diagrams indicate the amides and the boronic acid groups can be ionized forming strong ionic interactions with fluoride ions in addition to hydrogen bonding interactions.
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