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1. Fast and flexible strategy to produce electrochemical paper-based analytical devices using a craft cutter printer to create wax barrier and screen-printed electrodes

Author:
de Oliveira, Tássia Regina; Fonseca, Wilson Tiago; de Oliveira Setti, Grazielle; Faria, Ronaldo Censi
Source:
Talanta 2019 v.195 pp. 480-489
ISSN:
0039-9140
Subject:
ascorbic acid,   etc   ; acetaminophen; caffeine; cutting; detection limit; electrochemistry; electrodes; hydrophobicity;     Show all 8 Subjects
Abstract:
... This paper describes a simple, low-cost, and highly flexible rapid prototyping method to construct electrochemical paper-based analytical device (ePAD) for multiplexed analyte determinations. The ePAD was composed of two electrochemical cell (EC) compartments, separated by hydrophobic barriers of wax, and screen-printed electrodes (SPEs) deposited directly over the surface of the filter paper. The ...
DOI:
10.1016/j.talanta.2018.11.047

2. Redox-switchable atom transfer radical polymerization

Author:
Dadashi-Silab, Sajjad; Lorandi, Francesca; Fantin, Marco; Matyjaszewski, Krzysztof
Source:
Chemical communications 2019 v.55 no.5 pp. 612-615
ISSN:
1364-548X
Subject:
ascorbic acid,   etc   ; catalysts; copper; oxidants; oxidation; oxygen; polymerization; polymers;     Show all 8 Subjects
Abstract:
... Temporal control in atom transfer radical polymerization (ATRP) relies on modulating the oxidation state of a copper catalyst, as polymer chains are activated by L/Cuᴵ and deactivated by L/Cuᴵᴵ. (Re)generation of L/Cuᴵ activator has been achieved by applying a multitude of external stimuli. However, switching the Cu catalyst off by oxidizing to L/Cuᴵᴵ through external chemical stimuli has not yet ...
DOI:
10.1039/c8cc09209e

3. Study of Bi-directional detection for ascorbic acid and sodium nitrite based on Eu-containing luminescent polyoxometalate

Author:
Fu, Zhijing; Gao, Wenmei; Yu, Tian; Bi, Lihua
Source:
Talanta 2019 v.195 pp. 463-471
ISSN:
0039-9140
Subject:
ascorbic acid,   etc   ; color; detection limit; energy transfer; fluorescence; oxidants; photoluminescence; redox reactions; reducing agents; sodium nitrite;     Show all 10 Subjects
Abstract:
... Eu-containing polyoxometalate K13Eu(SiMoW10O39)2·28H2O (Eu-SiMoW) owns the stimu-chromic and photoluminescence properties. An ingenious test of ascorbic acid (AA) and sodium nitrite (NaNO2) was carried out based on the dual properties of Eu-SiMoW in solutions. First, the redox reaction of Eu-SiMoW and AA generated the blue reduced Eu-SiMoW, accompanied by fluorescence quenching; then the redox rea ...
DOI:
10.1016/j.talanta.2018.11.091

4. Multisyringe flow injection analysis (MSFIA) for the automatic determination of total iron in wines

Author:
Phansi, Piyawan; Danchana, Kaewta; Ferreira, Sergio L.C.; Cerdà, Víctor
Source:
Food chemistry 2019 v.277 pp. 261-266
ISSN:
0308-8146
Subject:
ascorbic acid,   etc   ; absorbance; flow injection analysis; iron; red wines; standard deviation; white wines;     Show all 7 Subjects
Abstract:
... This work presents a multisyringe flow injection analysis (MSFIA) system for the automatic spectrophotometric determination of total iron in wine. The reaction is based on the complexation of Fe(II) with 2-(5-bromo-2-pyridylazo)-5-(diethylamino)-phenol (Br-PADAP). Ascorbic acid was used as reducing reagent for Fe(III) to Fe(II) and, in this way, to determine the total iron content in wine. The abs ...
DOI:
10.1016/j.foodchem.2018.10.115

5. Evaluation of the composition of Chinese bayberry wine and its effects on the color changes during storage

Author:
Zhang, Zhengwei; Li, Jieying; Fan, Liuping
Source:
Food chemistry 2019 v.276 pp. 451-457
ISSN:
0308-8146
Subject:
ascorbic acid,   etc   ; Maillard reaction; Morella rubra; anthocyanins; color; hydroxymethylfurfural; kinetics; phenols; storage temperature; storage time; wines;     Show all 11 Subjects
Abstract:
... The color changes of Chinese bayberry wines during storage is a wide and urgent problem and its mechanism is still not clear. The changes of composition and color parameters of Chinese bayberry wines were studied during 70 days of storage in the dark at three different temperatures (4, 25 and 37 °C). The L∗, a∗, b∗, anthocyanins, total phenols, and total flavonoids decreased along with the increas ...
DOI:
10.1016/j.foodchem.2018.10.054

6. Self-assembled gold nanoclusters for fluorescence turn-on and colorimetric dual-readout detection of alkaline phosphatase activity via DCIP-mediated fluorescence resonance energy transfer

Author:
Han, Xue; Han, Ming; Ma, Lin; Qu, Fei; Kong, Rong-Mei; Qu, Fengli
Source:
Talanta 2019 v.194 pp. 55-62
ISSN:
0039-9140
Subject:
ascorbic acid,   etc   ; alkaline phosphatase; blood serum; colorimetry; energy transfer; enzyme activity; fluorescence; humans; hydrolysis; nanogold; polyallylamines;     Show all 11 Subjects
Abstract:
... We present a fluorescence turn-on and colorimetric dual-readout sensing system for the sensitive detection of alkaline phosphatase (ALP) activity via self-assembled gold nanoclusters (AuNCs) based on fluorescence resonance energy transfer (FRET). The positively charged polyallylamine hydrochloride (PAH)-crosslinked AuNCs (PAH-AuNCs) with aggregation-induced enhancement (AIE) characteristics can el ...
DOI:
10.1016/j.talanta.2018.09.108

7. Investigation of radio frequency heating as a dry-blanching method for carrot cubes

Author:
Gong, Chuting; Zhao, Yanyun; Zhang, Hangjin; Yue, Jin; Miao, Yubin; Jiao, Shunshan
Source:
Journal of food engineering 2019 v.245 pp. 53-56
ISSN:
0260-8774
Subject:
ascorbic acid,   etc   ; blanching; carrots; color; dielectric heating; electrodes; hardness; heat; peroxidase; radio waves; texture;     Show all 11 Subjects
Abstract:
... Radio frequency (RF) heating was investigated as a novel dry-blanching method for carrot cubes in this study. RF heating uniformity and effectiveness for inactivating peroxidase (POD) in carrot cubes were evaluated along with carrot quality (texture, color and vitamin C (Vc) content) after blanching. Results showed that RF heating uniformity increased with increasing RF electrode gap, and was affe ...
DOI:
10.1016/j.jfoodeng.2018.10.004

8. The stability of Fe(III)-As(V) co-precipitate in the presence of ascorbic acid: Effect of pH and Fe/As molar ratio

Author:
Yuan, Zidan; Zhang, Guoqing; Lin, Jinru; Zeng, Xiangfeng; Ma, Xu; Wang, Xin; Wang, Shaofeng; Jia, Yongfeng
Source:
Chemosphere 2019 v.218 pp. 670-679
ISSN:
0045-6535
Subject:
ascorbic acid,   etc   ; aerobic conditions; arsenic; hydroquinone; iron; oxalates; oxides; pH; quinones;     Show all 9 Subjects
Abstract:
... The potential hazards of Fe(III)-As(V) co-precipitate under reducing conditions are incompletely known. This work investigated the effect of Fe(III) reduction by ascorbic acid (AH2) on the stability of Fe(III)-As(V) co-precipitate at different pHs and Fe/As molar ratios. The results showed that As (14–98.9%) and Fe (27.9–99.3%) were significantly released into solution by 79.9–97.5% Fe(III) reduct ...
DOI:
10.1016/j.chemosphere.2018.11.142

9. Chitosan as a stabilizer and size-control agent for synthesis of porous flower-shaped palladium nanoparticles and their applications on photo-based therapies

Author:
Phan, Thi Tuong Vy; Hoang, Giang; Nguyen, Van Tu; Nguyen, Thanh Phuoc; Kim, Hye Hyun; Mondal, Sudip; Manivasagan, Panchanathan; Moorthy, Madhappan Santha; Lee, Kang Dae; Junghwan, Oh
Source:
Carbohydrate polymers 2019 v.205 pp. 340-352
ISSN:
0144-8617
Subject:
ascorbic acid,   etc   ; absorption; biocompatibility; chitosan; growth models; image analysis; nanoparticles; palladium; photothermotherapy; stabilizers;     Show all 10 Subjects
Abstract:
... This study reported a newly developed green synthesis method using chitosan and vitamin C to prepare porous flower–shaped palladium nanoparticles. We found that chitosan not only worked as a stabilizer but also as a size-control agent for the synthesis of these nanoparticles. The growth model of flower-shaped palladium nanoparticles was proposed to interpret mechanistic understanding. The obtained ...
DOI:
10.1016/j.carbpol.2018.10.062

10. A novel fluorescent probe for ascorbic acid based on seed-mediated growth of silver nanoparticles quenching of carbon dots fluorescence

Author:
Liu, Jinshui; Wang, Lizhen; Bao, Huijuan
Source:
Analytical and bioanalytical chemistry 2019 v.411 no.4 pp. 877-883
ISSN:
1618-2642
Subject:
ascorbic acid,   etc   ; carbon quantum dots; detection limit; energy transfer; fluorescence; fluorescent dyes; nanosilver; silver;     Show all 8 Subjects
Abstract:
... A novel, economic, and eco-friendly method of detecting ascorbic acid (AA) with excellent sensitivity was developed. The method took advantage of the fluorescence of carbon quantum dots (CDs) decreasing as the AA concentration increased through interactions between AA and Ag(I) in the presence of silver nanoparticle (AgNP) seeds, producing more AgNPs and allowing fluorescence resonance energy tran ...
DOI:
10.1007/s00216-018-1505-9

11. Enhanced remediation of arsenic and chromium co-contaminated soil by eletrokinetic-permeable reactive barriers with different reagents

Author:
Xu, Yunfeng; Li, Jiangpeng; Xia, Wei; Sun, Ying; Qian, Guangren; Zhang, Jia
Source:
Environmental science and pollution research international 2019 v.26 no.4 pp. 3392-3403
ISSN:
0944-1344
Subject:
ascorbic acid,   etc   ; X-ray diffraction; arsenic; chelating agents; chromium; polluted soils; reducing agents; remediation; sodium citrate;     Show all 9 Subjects
Abstract:
... The present work focused on the effects of different reagents on the remediation of arsenic and chromium co-contaminated soil by electrokinetic technology coupled with permeable reactive barrier (EK-PRB). In a running of EK-PRB, reductant (ascorbic acid, sodium citrate) and chelating agent (EDTA-2Na) were used to pretreat contaminated soil together with CaAl-LDH as reactive materials for PRB. As a ...
DOI:
10.1007/s11356-018-3842-9

12. High pressure impregnation (HPI) of apple cubes: Effect of pressure variables and carrier medium

Author:
Vatankhah, Hamed; Ramaswamy, Hosahalli S.
Source:
Food research international 2019 v.116 pp. 320-328
ISSN:
0963-9969
Subject:
ascorbic acid,   etc   ; apples; biocompatible materials; chitosan; drip loss; freeze-thaw cycles; freezing; models; texture; viscosity;     Show all 10 Subjects
Abstract:
... High pressure impregnation (HPI) is a novel technique to infuse desired fluids into porous biomaterials. In this study, the effect of 24 different pressure–time combination treatments were studied: come-up time (0 to 6 min), pressurization rate [100, 150, 200, 300 (MPa/min)] and pressure holding times (0–30 min) at 100, 300 & 600 MPa. Experiments were carried out based on HPI of ascorbic acid (AA) ...
DOI:
10.1016/j.foodres.2018.08.042

13. Light regulation of vitamin C in tomato fruit is mediated through photosynthesis

Author:
Ntagkas, Nikolaos; Woltering, Ernst; Nicole, Celine; Labrie, Caroline; Marcelis, Leo F.M.
Source:
Environmental and experimental botany 2019 v.158 pp. 180-188
ISSN:
0098-8472
Subject:
ascorbic acid,   etc   ; chlorophyll; fruiting; genotype; leaves; light intensity; lighting; photosynthesis; tomatoes;     Show all 9 Subjects
Abstract:
... Higher levels of irradiance result in higher accumulation of ascorbate in leaves and fruits. Photosynthesis and respiration are an integral part of the physiological mechanism of light regulation of ascorbate in leaves, but little is known about the light regulation of ascorbate in fruit. The aim of this study was to investigate whether fruit illumination alone is sufficient for ascorbate increase ...
DOI:
10.1016/j.envexpbot.2018.12.002

14. Point-of-use detection of ascorbic acid using a spectrometric smartphone-based system

Author:
Aguirre, Miguel Ángel; Long, Kenneth D.; Canals, Antonio; Cunningham, Brian T.
Source:
Food chemistry 2019 v.272 pp. 141-147
ISSN:
0308-8146
Subject:
ascorbic acid,   etc   ; liquid-phase microextraction; methylene blue; orange juice; quality control; spectral analysis; vitamin supplements;     Show all 7 Subjects
Abstract:
... A rapid and portable analytical methodology has been developed for ascorbic acid (Vitamin C) quantification from aqueous samples using a spectrometric smartphone-based system for the first time. The method employs point-of-use approaches both for sample preparation and sample measurement, demonstrating the capability for mobile quality control of pharmaceutical and food products. Our approach util ...
DOI:
10.1016/j.foodchem.2018.08.002

15. Highly Efficient Zn–Cu–In–Se Quantum Dot-Sensitized Solar Cells through Surface Capping with Ascorbic Acid

Author:
Zhang, Hua; Fang, Wenjuan; Wang, Wenran; Qian, Nisheng; Ji, Xiaohe
Source:
ACS applied materials & interfaces 2019 v.11 no.7 pp. 6927-6936
ISSN:
1944-8252
Subject:
ascorbic acid,   etc   ; copper; electrodes; energy; ligands; quantum dots; solar cells; titanium; zinc;     Show all 9 Subjects
Abstract:
... The balance between band structure, composition, and defect is essential for improving the optoelectronic properties of ternary and quaternary quantum dots and the corresponding photovoltaic performance. In this work, ascorbic acid (AA) as capping ligand is introduced into the reaction system to prepare green Zn–Cu–In–Se (ZCISe) quantum dots. Results show that the addition of AA can increase the Z ...
DOI:
10.1021/acsami.8b18033

16. Ultrasensitive Photoelectrochemical Detection of Multiple Metal Ions Based on Wavelength-Resolved Dual-Signal Output Triggered by Click Reaction

Author:
Deng, Han-Mei; Huang, Liao-Jing; Chai, Ya-Qin; Yuan, Ruo; Yuan, Ya-Li
Source:
Analytical chemistry 2019 v.91 no.4 pp. 2861-2868
ISSN:
1520-6882
Subject:
ascorbic acid,   etc   ; DNA; DNA fragmentation; biosensors; copper; detection limit; electrodes; lead; magnesium; metal ions; nanomaterials; neoplasms;     Show all 12 Subjects
Abstract:
... In this work, a click reaction-triggered wavelength-resolved dual-signal output photoelectrochemical (PEC) biosensor with DNAzymes-assisted cleavage recycling amplification was proposed for sensitive triplex metal ions assay. Substantial DNA fragments azido-S₁ and azido-S₂, derived from the Pb²⁺ (target 1) and Mg²⁺ (target 2) dependent cleavage cycle of DNAzymes, respectively, were grafted efficie ...
DOI:
10.1021/acs.analchem.8b04831

17. A new fluorescence reagent: Synthesis, characterization and application for speciation of arsenic (III)/(VI) species in tea samples

Author:
Öksüz, Nur; Saçmacı, Şerife; Saçmacı, Mustafa; Ülgen, Ahmet
Source:
Food chemistry 2019 v.270 pp. 579-584
ISSN:
0308-8146
Subject:
ascorbic acid,   etc   ; acidity; arsenic; fluorescence; fluorometry; ions; nitric acid; pH; statistical analysis; tea; temperature;     Show all 11 Subjects
Abstract:
... A sensitive and selective fluorimetric method for the rapid determination of trace amounts of As(III)/As(V) species in certain tea samples forms the basis of the study. 3′,6′-bis(diethylamino)-2-{[(1E)-(4,5-dimethyl-2-furyl)methylene]amino}spiro[isoindole-1,9′-xanthen]-3(2H)-one (DMBD), was synthesized and characterized as a new fluorescence reagent for the speciation of As(III)/As(V) species. As( ...
DOI:
10.1016/j.foodchem.2018.07.076

18. Bioavailability of coenzyme Q10 supplements depends on carrier lipids and solubilization

Author:
López-Lluch, Guillermo; del Pozo-Cruz, Jesús; Sánchez-Cuesta, Ana; Cortés-Rodríguez, Ana Belén; Navas, Plácido
Source:
Nutrition 2019 v.57 pp. 133-140
ISSN:
0899-9007
Subject:
ascorbic acid,   etc   ; bioavailability; blood; coenzyme Q10; cross-over studies; food preservatives; lipids; solubilization;     Show all 8 Subjects
Abstract:
... Bioavailability of supplements with coenzyme Q10 (CoQ10) in humans seems to depend on the excipients of formulations and on physiological characteristics of the individuals. The aim of this study was to determine which factors presented in CoQ10 supplements affect the different response to CoQ10 in humans.We tested seven different supplement formulations containing 100 mg of CoQ10 in 14 young, hea ...
DOI:
10.1016/j.nut.2018.05.020

19. Characterization of interactions of eggPC lipid structures with different biomolecules

Author:
Corrales Chahar, F.; Díaz, S.B.; Ben Altabef, A.; Gervasi, C.; Alvarez, P.E.
Source:
Chemistry and physics of lipids 2018 v.210 pp. 60-69
ISSN:
0009-3084
Subject:
ascorbic acid,   etc   ; egg yolk; liquids; phosphatidylcholines;     Show all 4 Subjects
Abstract:
... In this paper we study the interactions of two biomolecules (ascorbic acid and Annonacin) with a bilayer lipid membrane. Egg yolk phosphatidylcholine (eggPC) liposomes (in crystalline liquid state) were prepared in solutions of ascorbic acid (AA) at different concentration levels. On the other hand, liposomes were doped with Annonacin (Ann), a mono-tetrahydrofuran acetogenin (ACG), which is an eff ...
DOI:
10.1016/j.chemphyslip.2017.11.013

20. Vitamin C for the critically ill: Is the evidence strong enough?

Author:
L. Langlois, Pascal; Lamontagne, François
Source:
Nutrition 2019 v.60 pp. 185-190
ISSN:
0899-9007
Subject:
ascorbic acid; ascorbic acid deficiency,   etc   ; animal models; antioxidants; bioactive properties; blood serum; cortisol; guidelines; immunomodulation; inflammation; intravenous injection; metabolomics; mortality; patients; pharmacokinetics; repletion; retrospective studies; sepsis (infection); systematic review; therapeutics; thiamin;     Show all 21 Subjects
Abstract:
... Vitamin C exhibits interesting properties in the context of critical illness, with benefits described in neurologic, cardiovascular, renal, and hematologic systems, both in in vitro and in animal models. Through direct effects on bacterial replication, immunomodulation, and antioxidant reserve of the organism, vitamin C directly affects the pathophysiological process of sepsis, trauma, burn, and s ...
DOI:
10.1016/j.nut.2018.10.009