The Experts below are selected from a list of 87669 Experts worldwide ranked by ideXlab platform
Matteo Ghittorelli - One of the best experts on this subject based on the ideXlab platform.
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high sensitivity Ion detectIon at low voltages with current driven organic electrochemical transistors
Nature Communications, 2018Co-Authors: Paolo Romele, Zsolt Miklos Kovacsvajna, Paul W M Blom, Matteo Ghittorelli, Leona V Lingstedt, Irina N Crăciun, Fabrizio TorricelliAbstract:Ions dissolved in aqueous media play a fundamental role in plants, animals, and humans. Therefore, the in situ quantificatIon of the Ion concentratIon in aqueous media is gathering relevant interest in several fields including biomedical diagnostics, environmental monitoring, healthcare products, water and food test and control, agriculture industry and security. The fundamental limitatIon of the state-of-art transistor-based approaches is the intrinsic trade-off between sensitivity, Ion concentratIon range and operating voltage. Here we show a current-driven configuratIon based on organic electrochemical transistors that overcomes this fundamental limit. The measured Ion sensitivity exceeds by one order of magnitude the Nernst limit at an operating voltage of few hundred millivolts. The Ion sensitivity normalized to the supply voltage is larger than 1200 mV V−1 dec−1, which is the largest value ever reported for Ion-sensitive transistors. The proposed approach is general and can be extended to any transistor technology, thus opening opportunities for high-performance bioelectronics.
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high sensitivity Ion detectIon at low voltages with current driven organic electrochemical transistors
Nature Communications, 2018Co-Authors: Paolo Romele, Zsolt Miklos Kovacsvajna, Paul W M Blom, Matteo Ghittorelli, Leona V Lingstedt, Irina N Crăciun, Fabrizio TorricelliAbstract:Ions dissolved in aqueous media play a fundamental role in plants, animals, and humans. Therefore, the in situ quantificatIon of the Ion concentratIon in aqueous media is gathering relevant interest in several fields including biomedical diagnostics, environmental monitoring, healthcare products, water and food test and control, agriculture industry and security. The fundamental limitatIon of the state-of-art transistor-based approaches is the intrinsic trade-off between sensitivity, Ion concentratIon range and operating voltage. Here we show a current-driven configuratIon based on organic electrochemical transistors that overcomes this fundamental limit. The measured Ion sensitivity exceeds by one order of magnitude the Nernst limit at an operating voltage of few hundred millivolts. The Ion sensitivity normalized to the supply voltage is larger than 1200 mV V−1 dec−1, which is the largest value ever reported for Ion-sensitive transistors. The proposed approach is general and can be extended to any transistor technology, thus opening opportunities for high-performance bioelectronics. The organic electrochemical transistor is a type of transistor that modulates the channel current by the Ion concentratIon and is thus explored for bio-applicatIons. Here Ghittorelli et al. show a current-driven device configuratIon to increase the sensitivity by ten times than conventIonal approaches.
Carles Codina - One of the best experts on this subject based on the ideXlab platform.
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identificatIon of phenolic compounds in artichoke waste by high performance liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2003Co-Authors: Ferran Sanchezrabaneda, Olga Jauregui, Rosa M Lamuelaraventos, Jaume Bastida, Francesc Viladomat, Carles CodinaAbstract:A new fast and efficient method combining liquid chromatography coupled to Ionspray mass spectrometry in tandem mode with negative Ion detectIon is described for the qualitative analysis of artichoke waste. Forty-five phenolic compounds were identified on the basis of their mass spectra in full scan mode, mass spectra in different MS-MS modes, and retentIon times compared with those of available reference substances. The major compounds were found to be both caffeoylquinic and dicaffeoylquinic acids, luteolin glucuronide, luteolin galactoside, quercetin, and some quercetin glycosides.
Jong Seung Kim - One of the best experts on this subject based on the ideXlab platform.
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a highly selective colorimetric and ratiometric two photon fluorescent probe for fluoride Ion detectIon
Organic Letters, 2011Co-Authors: Jun Feng Zhang, Chang Su Lim, Bong Rae Cho, Sankarprasad Bhuniya, Jong Seung KimAbstract:A naphthalimide-based highly selective colorimetric and ratiometric fluorescent probe for the fluoride Ion displayed both one- and two-photon ratiometric changes. Upon reactIon with the F(-) (TBA(+) and Na(+) salts) anIon in CH(3)CN as well as in aqueous buffer solutIon, probe 1 shows dramatic color changes from colorless to jade-green and remarkable ratiometric fluorescence enhancements signals. These properties are mechanistically ascribed to a fluoride-triggered Si-O bond cleavage that resulted in a green fluorescent 4-amino-1,8-naphthalimide.
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fluoro and chromogenic chemodosimeters for heavy metal Ion detectIon in solutIon and biospecimens
Chemical Reviews, 2010Co-Authors: Duong Tuan Quang, Jong Seung KimAbstract:Heavy metal Ions are of great concern, not only among the scientific community, especially chemists, biologists, and environmentalists, but increasingly among the general populatIon, who are aware of the some of the disadvantages associated with them. In spite of the fact that some heavy metal Ions play important roles in living systems, they are very toxic and hence capable of causing serious environmental and health problems.1-6 Some heavy metal Ions, such as Fe(III), Zn(II), Cu(II), Co(II), Mn(II), and Mo(VI), are essential for the maintenance of human metabolism. However, high concentratIons of these Ions can lead to many adverse health effects.1,2,7-20 It is also a fact that others such as Hg(II), Cd(II), Pb(II), and As(III) are among the most toxic Ions known that lack any vital or beneficial effects. AccumulatIon of these over time in the bodies of humans and animals can lead to serious debilitating illnesses.2,21-30 Therefore, the development of increasingly selective and sensitive methods for the determinatIon of heavy metal Ions is currently receiving considerable attentIon.7,23,31-36 Several methods, including atomic absorptIon spectroscopy, inductively coupled plasma atomic emissIon spectrometry, electrochemical sensoring, and the use of piezoelectric quartz crystals make it possible to detect low limits.37-40 However, these methods require expensive equipment and involve time-consuming and laborious procedures that can be carried out only by trained professIonals. Alternatively, analytical techniques based on fluorescence detectIon are very popular because fluorescence measurements are usually very sensitive (parts per billIon/trillIon), easy to perform, and inexpensive.23,37,41-45 Furthermore, the photophysical properties of a fluorophore can be easily tuned using a range of routes: charge transfer, electron transfer, energy transfer, the influence of the heavy metal Ions, and the destabilizatIon of nonemissive n-π* excited states.5 Consequently, a large number of papers involving fluorescent chemosensors (see definitIon in sectIon 2) have been published. In general to date, fluorescent chemosensors for anIons and catIons have proven popular, but those for many heavy metal Ions such as Hg(II), Pb(II), Cu(II), Fe(III), and Ag(I) present challenges because these Ions often act as fluorescence quenchers. Cu(II) is a typical Ion that causes the chemosensor to decrease fluorescent emissIons due to quenching of the fluorescence by mechanisms inherent to the paramagnetic species.46-48 Such decreased emissIons are impractical for analytical purposes because of their low signal outputs upon complexatIon. In additIon, temporal separatIon of spectrally similar complexes by time-resolved fluorimetry is subsequently prevented.49 Compared to the relatively well-developed fluorescent chemosensors, fluorescent chemodosimeters (see definitIon in sectIon 2) have recently emerged as a research area of * Corresponding author. E-mail: jongskim@korea.ac.kr. † Hue University. ‡ Korea University. Duong Tuan Quang was born in 1970 in Thanhhoa, Vietnam, and graduated from Hue University in 1992, where he obtained his M.S. degree two years later and began his career as a lecturer in Chemistry soon afterwards. He received his Ph.D. degree in 2003 from Institute of Chemistry, Vietnamese Academy of Science and Technology. In 2006, he worked as a postdoctoral fellow in Professor Jong Seung Kim’s laboratory, Dankook University, Seoul, Korea. He was promoted as an associate professor in 2009 and went to Korea University as a research professor in 2010. His main task involved the development of chromogenic and fluorogenic molecular sensors to detect specific catIons and anIons. Chem. Rev. 2010, 110, 6280–6301 6280
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fluoro and chromogenic chemodosimeters for heavy metal Ion detectIon in solutIon and biospecimens
Chemical Reviews, 2010Co-Authors: Duong Tuan Quang, Jong Seung KimAbstract:Heavy metal Ions are of great concern, not only among the scientific community, especially chemists, biologists, and environmentalists, but increasingly among the general populatIon, who are aware of the some of the disadvantages associated with them. In spite of the fact that some heavy metal Ions play important roles in living systems, they are very toxic and hence capable of causing serious environmental and health problems.1-6 Some heavy metal Ions, such as Fe(III), Zn(II), Cu(II), Co(II), Mn(II), and Mo(VI), are essential for the maintenance of human metabolism. However, high concentratIons of these Ions can lead to many adverse health effects.1,2,7-20 It is also a fact that others such as Hg(II), Cd(II), Pb(II), and As(III) are among the most toxic Ions known that lack any vital or beneficial effects. AccumulatIon of these over time in the bodies of humans and animals can lead to serious debilitating illnesses.2,21-30 Therefore, the development of increasingly selective and sensitive methods for the determinatIon of heavy metal Ions is currently receiving considerable attentIon.7,23,31-36 Several methods, including atomic absorptIon spectroscopy, inductively coupled plasma atomic emissIon spectrometry, electrochemical sensoring, and the use of piezoelectric quartz crystals make it possible to detect low limits.37-40 However, these methods require expensive equipment and involve time-consuming and laborious procedures that can be carried out only by trained professIonals. Alternatively, analytical techniques based on fluorescence detectIon are very popular because fluorescence measurements are usually very sensitive (parts per billIon/trillIon), easy to perform, and inexpensive.23,37,41-45 Furthermore, the photophysical properties of a fluorophore can be easily tuned using a range of routes: charge transfer, electron transfer, energy transfer, the influence of the heavy metal Ions, and the destabilizatIon of nonemissive n-π* excited states.5 Consequently, a large number of papers involving fluorescent chemosensors (see definitIon in sectIon 2) have been published. In general to date, fluorescent chemosensors for anIons and catIons have proven popular, but those for many heavy metal Ions such as Hg(II), Pb(II), Cu(II), Fe(III), and Ag(I) present challenges because these Ions often act as fluorescence quenchers. Cu(II) is a typical Ion that causes the chemosensor to decrease fluorescent emissIons due to quenching of the fluorescence by mechanisms inherent to the paramagnetic species.46-48 Such decreased emissIons are impractical for analytical purposes because of their low signal outputs upon complexatIon. In additIon, temporal separatIon of spectrally similar complexes by time-resolved fluorimetry is subsequently prevented.49 Compared to the relatively well-developed fluorescent chemosensors, fluorescent chemodosimeters (see definitIon in sectIon 2) have recently emerged as a research area of * Corresponding author. E-mail: jongskim@korea.ac.kr. † Hue University. ‡ Korea University. Duong Tuan Quang was born in 1970 in Thanhhoa, Vietnam, and graduated from Hue University in 1992, where he obtained his M.S. degree two years later and began his career as a lecturer in Chemistry soon afterwards. He received his Ph.D. degree in 2003 from Institute of Chemistry, Vietnamese Academy of Science and Technology. In 2006, he worked as a postdoctoral fellow in Professor Jong Seung Kim’s laboratory, Dankook University, Seoul, Korea. He was promoted as an associate professor in 2009 and went to Korea University as a research professor in 2010. His main task involved the development of chromogenic and fluorogenic molecular sensors to detect specific catIons and anIons. Chem. Rev. 2010, 110, 6280–6301 6280
Hongku Shim - One of the best experts on this subject based on the ideXlab platform.
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catIonic conjugated polyelectrolytes triggered conformatIonal change of molecular beacon aptamer for highly sensitive and selective potassium Ion detectIon
Journal of the American Chemical Society, 2012Co-Authors: In Hwan Jung, Mijeong Kang, Hongku ShimAbstract:We demonstrate highly sensitive and selective potassium Ion detectIon against excess sodium Ions in water, by modulating the interactIon between the G-quadruplex-forming molecular beacon aptamer (MBA) and catIonic conjugated polyelectrolyte (CPE). The K+-specific aptamer sequence in MBA is used as the molecular recognitIon element, and the high binding specificity of MBA for potassium Ions offers selectivity against a range of metal Ions. The hairpin-type MBA labeled with a fluorophore and quencher at both termini undergoes a conformatIonal change (by complexatIon with CPEs) to either an open-chain form or a G-quadruplex in the absence or presence of K+ Ions. ConformatIonal changes of MBA as well as fluorescence (of the fluorophore in MBA) quenching or amplificatIon via fluorescence resonance energy transfer from CPEs provide clear signal turn-off and -on in the presence or absence of K+. The detectIon limit of the K+ assays is determined to be ∼1.5 nM in the presence of 100 mM Na+ Ions, which is ∼3 order...
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catIonic conjugated polyelectrolytes triggered conformatIonal change of molecular beacon aptamer for highly sensitive and selective potassium Ion detectIon
Journal of the American Chemical Society, 2012Co-Authors: Boram Kim, In Hwan Jung, Mijeong Kang, Hongku Shim, Han Young WooAbstract:We demonstrate highly sensitive and selective potassium Ion detectIon against excess sodium Ions in water, by modulating the interactIon between the G-quadruplex-forming molecular beacon aptamer (MBA) and catIonic conjugated polyelectrolyte (CPE). The K(+)-specific aptamer sequence in MBA is used as the molecular recognitIon element, and the high binding specificity of MBA for potassium Ions offers selectivity against a range of metal Ions. The hairpin-type MBA labeled with a fluorophore and quencher at both termini undergoes a conformatIonal change (by complexatIon with CPEs) to either an open-chain form or a G-quadruplex in the absence or presence of K(+) Ions. ConformatIonal changes of MBA as well as fluorescence (of the fluorophore in MBA) quenching or amplificatIon via fluorescence resonance energy transfer from CPEs provide clear signal turn-off and -on in the presence or absence of K(+). The detectIon limit of the K(+) assays is determined to be ~1.5 nM in the presence of 100 mM Na(+) Ions, which is ~3 orders of magnitude lower than those reported previously. The successful detectIon of 5'-adenosine triphosphate (ATP) with the MBA containing an ATP-specific aptamer sequence is also demonstrated using the same sensor scheme. The scheme reported herein is applicable to the detectIon of other kinds of G-rich aptamer-binding chemicals and biomolecules.
Fabrizio Torricelli - One of the best experts on this subject based on the ideXlab platform.
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integrated amplifier with complementary organic electrochemical transistors for high sensitivity Ion detectIon and real time monitoring
Integrated Sensors for Biological and Neural Sensing, 2021Co-Authors: Fabrizio Torricelli, Paolo Romele, Paschalis Gkoupidenis, Dimitrios A Koutsouras, Katharina Lieberth, Zsolt Miklos Kovacsvajna, Paul W M BlomAbstract:Ions are fundamental biological regulators enabling the communicatIon between cells, regulating metabolic and bioenergetic processing and playing a key role in pH regulatIon and hydratIon. The in-situ quantificatIon of the Ion concentratIon is gathering relevant interest in biomedical diagnostics and healthcare. State-of-art transistor-based Ion sensors show an intrinsic trade-off between sensitivity, operating range and supply voltage. To overcome these limitatIons, here we focus on Ion sensor amplifiers where complementary OECTs are integrated in a push-pull configuratIon, providing sensitivity larger than 1 V/dec at a supply voltage down to 0.5 V and operating in the physiological range. Ion detectIon over a range of five orders of magnitude and real-time monitoring of variatIons two orders of magnitude lower than the detected concentratIon are achieved. The Ion-sensitive amplifier sets a new benchmark for Ion-sensing devices, opening possibilities for predictive diagnostics and personalized medicine.
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high sensitivity Ion detectIon at low voltages with current driven organic electrochemical transistors
Nature Communications, 2018Co-Authors: Paolo Romele, Zsolt Miklos Kovacsvajna, Paul W M Blom, Matteo Ghittorelli, Leona V Lingstedt, Irina N Crăciun, Fabrizio TorricelliAbstract:Ions dissolved in aqueous media play a fundamental role in plants, animals, and humans. Therefore, the in situ quantificatIon of the Ion concentratIon in aqueous media is gathering relevant interest in several fields including biomedical diagnostics, environmental monitoring, healthcare products, water and food test and control, agriculture industry and security. The fundamental limitatIon of the state-of-art transistor-based approaches is the intrinsic trade-off between sensitivity, Ion concentratIon range and operating voltage. Here we show a current-driven configuratIon based on organic electrochemical transistors that overcomes this fundamental limit. The measured Ion sensitivity exceeds by one order of magnitude the Nernst limit at an operating voltage of few hundred millivolts. The Ion sensitivity normalized to the supply voltage is larger than 1200 mV V−1 dec−1, which is the largest value ever reported for Ion-sensitive transistors. The proposed approach is general and can be extended to any transistor technology, thus opening opportunities for high-performance bioelectronics.
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high sensitivity Ion detectIon at low voltages with current driven organic electrochemical transistors
Nature Communications, 2018Co-Authors: Paolo Romele, Zsolt Miklos Kovacsvajna, Paul W M Blom, Matteo Ghittorelli, Leona V Lingstedt, Irina N Crăciun, Fabrizio TorricelliAbstract:Ions dissolved in aqueous media play a fundamental role in plants, animals, and humans. Therefore, the in situ quantificatIon of the Ion concentratIon in aqueous media is gathering relevant interest in several fields including biomedical diagnostics, environmental monitoring, healthcare products, water and food test and control, agriculture industry and security. The fundamental limitatIon of the state-of-art transistor-based approaches is the intrinsic trade-off between sensitivity, Ion concentratIon range and operating voltage. Here we show a current-driven configuratIon based on organic electrochemical transistors that overcomes this fundamental limit. The measured Ion sensitivity exceeds by one order of magnitude the Nernst limit at an operating voltage of few hundred millivolts. The Ion sensitivity normalized to the supply voltage is larger than 1200 mV V−1 dec−1, which is the largest value ever reported for Ion-sensitive transistors. The proposed approach is general and can be extended to any transistor technology, thus opening opportunities for high-performance bioelectronics. The organic electrochemical transistor is a type of transistor that modulates the channel current by the Ion concentratIon and is thus explored for bio-applicatIons. Here Ghittorelli et al. show a current-driven device configuratIon to increase the sensitivity by ten times than conventIonal approaches.
