journal
MENU ▼
Read by QxMD icon Read
search

Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy

journal
https://www.readbyqxmd.com/read/28810180/classification-and-quantitation-of-milk-powder-by-near-infrared-spectroscopy-and-mutual-information-based-variable-selection-and-partial-least-squares
#1
Hui Chen, Chao Tan, Zan Lin, Tong Wu
Milk is among the most popular nutrient source worldwide, which is of great interest due to its beneficial medicinal properties. The feasibility of the classification of milk powder samples with respect to their brands and the determination of protein concentration is investigated by NIR spectroscopy along with chemometrics. Two datasets were prepared for experiment. One contains 179 samples of four brands for classification and the other contains 30 samples for quantitative analysis. Principal component analysis (PCA) was used for exploratory analysis...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28810179/utility-of-ultrasound-assisted-cloud-point-extraction-and-spectophotometry-as-a-preconcentration-and-determination-tool-for-the-sensitive-quantification-of-mercury-species-in-fish-samples
#2
Nail Altunay
The current study reports, for the first time, the development of a new analytical method employing ultrasound assisted-cloud point extraction (UA-CPE) for the extraction of CH3Hg(+) and Hg(2+) species from fish samples. Detection and quantification of mercury species were performed at 550nm by spectrophotometry. The analytical variables affecting complex formation and extraction efficiency were extensively evaluated and optimized by univariate method. Due to behave 14-fold more sensitive and selective of thiophene 2,5-dicarboxylic acid (H2TDC) to Hg(2+) ions than CH3Hg(+) in presence of mixed surfactant, Tween 20 and SDS at pH5...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28810178/distance-dependent-fluorescence-quenching-and-enhancement-of-gold-nanoclusters-by-gold-nanoparticles
#3
Haiyan Qin, Diao Ma, Jianxiu Du
The interaction between fluorescent gold nanoclusters (AuNCs) and gold nanoparticles (AuNPs) has been investigated. It was observed that the fluorescence of AuNCs was remarkably quenched when direct contact with AuNPs. The fluorescence quenching of AuNCs by AuNPs was dynamic quenching and exhibited size-dependent property. A larger size of AuNPs displayed a stronger quenching effect and gave a larger quenching constant. When a silica spacer shell was introduced between AuNPs and AuNCs, a fluorescence enhancement of AuNCs by Au@SiO2 NPs was observed...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28806701/application-of-different-spectrophotometric-methods-for-simultaneous-determination-of-elbasvir-and-grazoprevir-in-pharmaceutical-preparation
#4
Khalid A M Attia, Nasr M El-Abasawi, Ahmed El-Olemy, Ahmed H Abdelazim
The first three UV spectrophotometric methods have been developed of simultaneous determination of two new FDA approved drugs namely; elbasvir and grazoprevir in their combined pharmaceutical dosage form. These methods include simultaneous equation, partial least squares with and without variable selection procedure (genetic algorithm). For simultaneous equation method, the absorbance values at 369 (λmax of elbasvir) and 253nm (λmax of grazoprevir) have been selected for the formation of two simultaneous equations required for the mathematical processing and quantitative analysis of the studied drugs...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28806700/a-large-raman-scattering-cross-section-molecular-embedded-sers-aptasensor-for-ultrasensitive-aflatoxin-b1-detection-using-cs-fe3o4-for-signal-enrichment
#5
Quansheng Chen, Mingxiu Yang, Xiaojing Yang, Huanhuan Li, Zhiming Guo, M H Rahma
With growing concern on oil safety problems, developing a simple and sensitive method to detect Aflatoxin B1 (AFB1), a common mycotoxin in peanut oil, is very necessary. In this study, Surface-enhanced Raman Scattering (SERS) aptasensor was developed for ultrasensitive AFB1 detection using the amino-terminal AFB1 aptamer (NH2-DNA1); and thiol-terminal AFB1 complementary aptamer (SH-DNA2) conjugated magnetic-beads (CS-Fe3O4) as enrichment nanoprobe and AuNR@DNTB@Ag nanorods (ADANRs) as reporter nanoprobe respectively...
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28806697/photoelectron-spectra-and-biological-activity-of-cinnamic-acid-derivatives-revisited
#6
Igor Novak, Leo Klasinc, Sean P McGlynn
The electronic structures of several derivatives of cinnamic acid have been studied by UV photoelectron spectroscopy (UPS) and Green's function quantum chemical calculations. The spectra reveal the presence of dimers in the gas phase for p-coumaric and ferulic acids. The electronic structure analysis has been related to the biological properties of these compounds through the analysis of some structure-activity relationships (SAR).
August 10, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28802161/physicochemical-analysis-of-permian-coprolites-from-brazil
#7
M I C Rodrigues, J H da Silva, F Eroni P Santos, P Dentzien-Dias, J C Cisneros, A S de Menezes, P T C Freire, B C Viana
In this paper we performed the study of two coprolites (fossilized feces) collected from the exposed levels of the Pedra de Fogo Formation, Parnaiba Sedimentary Basin, and Rio do Rasto Formation, Paraná Sedimentary Basin, both of the Palaeozoic era (Permian age). They were characterized using X-ray diffractometry, infrared, Raman and energy dispersive spectroscopy techniques in order to aid our understanding of the processes of fossilization and to discuss issues related to the feeding habits of the animals which generated those coprolites, probably cartilaginous fishes...
August 8, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28806698/fluorescence-and-electron-paramagnetic-resonance-studies-of-norfloxacin-and-n-donor-mixed-ligand-ternary-copper-ii-complexes-stability-and-interaction-with-sds-micelles
#8
Gabriel S Vignoli Muniz, Jimmy Llontop Incio, Odivaldo C Alves, Klaus Krambrock, Letícia R Teixeira, Sonia R W Louro
The stability of ternary copper(II) complexes of a heterocyclic ligand, L (L being 2,2'-bipyridine (bipy) or 1,10-phenanthroline (phen)) and the fluorescent antibacterial agent norfloxacin (NFX) as the second ligand was studied at pH7.4 and different ionic strengths. Fluorescence quenching upon titration of NFX with the binary complexes allowed to obtain stability constants for NFX binding, Kb, as a function of ionic strength. The Kb values vary by more than two orders of magnitude when buffer concentration varies from 0...
August 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28802856/different-mathematical-processing-of-absorption-ratio-and-derivative-spectra-for-quantification-of-mixtures-containing-minor-component-an-application-to-the-analysis-of-the-recently-co-formulated-antidiabetic-drugs-canagliflozin-and-metformin
#9
Hayam M Lotfy, Dalia Mohamed, Mona S Elshahed
In the presented work several spectrophotometric methods were performed for the quantification of canagliflozin (CGZ) and metformin hydrochloride (MTF) simultaneously in their binary mixture. Two of these methods; response correlation (RC) and advanced balance point-spectrum subtraction (ABP-SS) were developed and introduced for the first time in this work, where the latter method (ABP-SS) was performed on both the zero order and the first derivative spectra of the drugs. Besides, two recently established methods; advanced amplitude modulation (AAM) and advanced absorbance subtraction (AAS) were also accomplished...
August 5, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28797842/carbon-dot-based-dual-emission-silica-nanoparticles-as-a-ratiometric-fluorescent-probe-for-vanadium-v-detection-in-mineral-water-samples
#10
Lijun He, Heng Zhang, Huanhuan Fan, Xiuming Jiang, Wenjie Zhao, Guo Qiang Xiang
Herein, we propose a simple and effective strategy for designing a ratiometric fluorescent nanosensor. We designed and developed a carbon dots (CDs) based dual-emission nanosensor for vanadium(V) by coating the surface of dye-doped silica nanoparticles with CDs. The fluorescence of dual-emission silica nanoparticles was quenched in acetic acid through potassium bromate (KBrO3) oxidation. V(V) could catalyze KBrO3 oxidation reaction process, resulting in the ratiometric fluorescence quenching of dual-emission silica nanoparticles...
August 4, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28797841/a-cr-vi-selective-probe-based-on-a-quinoline-amide-calix-4-arene
#11
Juliane F Ferreira, Izilda A Bagatin
A new quinoline-amide calix[4]arene 3-receptor for detection of hazardous anions and cations have been synthesized. The 3-receptor was examined for its sensing properties towards several different anions (Cr2O7(2-), SCN(-), F(-), Cl(-), NO3) and metal ions (Hg(2+), Cd(2+), Ag(+)) by UV-vis and fluorescence spectroscopies. It was detected that the 3-receptor has only sensing ability for Cr2O7(2-) and Hg(2+) ions, resulting in the association constants higher for Cr2O7(2-) than to the Hg(2+) ions. High selectivity towards Cr2O7(2-) were also observed by fluorescence measurement among other ions (F(-), Cl(-), SCN(-), Hg(2+), Cd(2+), Ag(+)) with a low limit of detection (7...
August 3, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28787624/fluorescence-emission-induced-by-the-femtosecond-filament-transmitting-through-the-butane-air-flame
#12
Suyu Li, Yanhua Li, Zhe Shi, Laizhi Sui, He Li, Qingyi Li, Anmin Chen, Yuanfei Jiang, Mingxing Jin
We measure the backward fluorescence spectra generated by the femtosecond filament transmitting through the butane/air flame, and study the fluorescence emission from combustion intermediates (CN, CH and C2 radicals), air (mainly N2 and N2(+)). It is found that the fluorescence emission from combustion intermediates, N2 and N2(+) shows difference when the femtosecond filament transmits through different parts of the butane/air flame, and we attempt to analyze it in this paper. This study demonstrates that the filament-induced fluorescence technique can be utilized to sense the combustion intermediates...
August 3, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28787622/attaching-naphthalene-derivatives-onto-bodipy-for-generating-excited-triplet-state-and-singlet-oxygen-tuning-pet-based-photosensitizer-by-electron-donors
#13
Xian-Fu Zhang, Nan Feng
meso-Naphthalene substituted BODIPY compounds were prepared in a facile one pot reaction. The naphthalene functionalization of BODIPY leads up to a 5-fold increase in the formation efficiency of excited triplet state and singlet oxygen in polar solvents. Steady state and time resolved fluorescence, laser flash photolysis, and quantum chemistry methods were used to reveal the mechanism. All measured data and quantum chemical results suggest that these systems can be viewed as electron donor-acceptor (D-A) pair (BODIPY acts as the acceptor), photoinduced charge transfer (PCT) or photoinduced electron transfer (PET) occurs upon photo excitation (D-A+hν→D(δ+)-A(δ-), 0<δ≤1), and the charge recombination induced the formation of triplet state (D(δ+)-A(δ-)→D-A (T1)...
August 3, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28783587/-turn-on-fluorescent-probe-for-detection-of-h2s-and-its-applications-in-bioimaging
#14
Qi Zhao, Jin Kang, Ying Wen, Fangjun Huo, Yongbin Zhang, Caixia Yin
A novel fluorescent probe (named YQ-1) containing disulfide-bond coumarin derivative was developed for H2S. In response to H2S, YQ-1 showed remarkable fluorescent emission enhancement at 462nm. Besides, YQ-1 exhibited higher selectivity, faster response rate, low cytotoxicity and low detection limit (0.052μM). Further, YQ-1 was used to detect the presence of H2S level in living A549 cells, indicating YQ-1 has good membrane permeability and fluorescence properties.
August 3, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28787623/a-new-fluorene-based-schiff-base-as-fluorescent-chemosensor-for-selective-detection-of-cr-3-and-al-3
#15
Mahmood Tajbakhsh, Gholam Babaei Chalmardi, Ahmadreza Bekhradnia, Rahman Hosseinzadeh, Nahid Hasani, Mohammadreza Azizi Amiri
2-((9H-fluoren-2-ylimino) methyl)phenol (F3) was synthesized by condensation reaction of 9H-fluoren-2-amine and 2-hydroxybenzaldehyde in EtOH and characterized by its melting point, (1)H-,(13)C NMR and molecular mass. F3 exhibits a high selectivity for detection of Cr(3+) and Al(3+) ions as a fluorescent chemosensor and showed a single emission band at 536nm upon excitation at 333nm according to fluorescence emission studies. The addition of Cr(3+) and Al(3+) make a significant increase in fluorescent intensity at 536nm in CH3CN, while other metal ions have almost no influence on the fluorescence...
August 2, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28783586/dynamic-surface-enhanced-raman-spectroscopy-and-chemometric-methods-for-fast-detection-and-intelligent-identification-of-methamphetamine-and-3-4-methylenedioxy-methamphetamine-in-human-urine
#16
Shizhuang Weng, Ronglu Dong, Zede Zhu, Dongyan Zhang, Jinling Zhao, Linsheng Huang, Dong Liang
Conventional Surface-Enhanced Raman Spectroscopy (SERS) for fast detection of drugs in urine on the portable Raman spectrometer remains challenges because of low sensitivity and unreliable Raman signal, and spectra process with manual intervention. Here, we develop a novel detection method of drugs in urine using chemometric methods and dynamic SERS (D-SERS) with mPEG-SH coated gold nanorods (GNRs). D-SERS combined with the uniform GNRs can obtain giant enhancement, and the signal is also of high reproducibility...
August 2, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28806699/a-portable-synthesis-of-water-soluble-carbon-dots-for-highly-sensitive-and-selective-detection-of-chlorogenic-acid-based-on-inner-filter-effect
#17
Huan Yang, Liu Yang, Yusheng Yuan, Shuang Pan, Jidong Yang, Jingjing Yan, Hui Zhang, Qianqian Sun, Xiaoli Hu
In this work, a simple and facile hydrothermal method for synthesis of water-soluble carbon dots (CDs) with malic acid and urea, and were then employed as a high-performance fluorescent probe for selective and sensitive determination of chlorogenic acid (CGA) based on inner filter effect. The as-synthesized CDs was systematically characterized by Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Energy disperse spectroscopy (EDS), UV-vis absorption spectroscopy, spectrofluorophotometry, and the results indicated that the sizes of CDs were mainly distributed in the range of 1...
August 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28803123/highly-selective-on-off-fluorescence-recognition-of-fe-3-based-on-a-coumarin-derivative-and-its-application-in-live-cell-imaging
#18
Sona Warrier, Prashant S Kharkar
A novel coumarin chemosensor, 7-hydroxy-2-oxo-N-(pyridin-2-ylmethyl)chromene-3-carboxamide (Probe 1), demonstrated significant selectivity towards Fe(3+) ions. Probe 1 exhibited high fluorescence emission profile at 447nm, excellent selectivity towards Fe(3+) over other biologically important metal ions (Al(3+), Ba(2+), Co(2+), Cu(2+), Zn(2+), Cd(2+), Hg(2+), Pb(2+) and Sn(2+)). Interestingly, there was ~30-fold decrease in fluorescence intensity upon Fe(3+) binding. The limit of detection of Fe(3+) was found to be 0...
August 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28802857/spectrophotometric-methods-for-the-determination-of-urea-in-real-samples-using-silver-nanoparticles-by-standard-addition-and-2nd-order-derivative-methods
#19
Nauman Ali, Muhammad Ismail, Adnan Khan, Hamayun Khan, Sajjad Haider, Tahseen Kamal
In this work, we have developed simple, sensitive and inexpensive methods for the spectrophotometric determination of urea in urine samples using silver nanoparticles (AgNPs). The standard addition and 2nd order derivative methods were adopted for this purpose. AgNPs were prepared by chemical reduction of AgNO3 with hydrazine using 1,3-di-(1H-imidazol-1-yl)-2-propanol (DIPO) as a stabilizing agent in aqueous medium. The proposed methods were based on the complexation of AgNPs with urea. Using this concept, urea in the urine samples was successfully determined spectrophotometric methods...
August 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28800432/linear-and-circular-dichroism-characterization-of-thionine-binding-mode-with-dna-polynucleotides
#20
Eimer Mary Tuite, Bengt Nordén
The binding mode of thionine (3,7-diamino-5-phenothiazinium) with alternating and non-alternating DNA polynucleotides at low binding ratios was conclusively determined using linear and circular dichroism spectroscopies. The binding to [poly(dG-dC)]2 and poly(dG)·poly(dC) was purely intercalative and was insensitive to ionic strength. Intercalative binding to [poly(dA-dT)]2 is observed at low ionic strength, but a shift of some dye to an non-intercalative mode is observed as the background salt concentration increases...
August 1, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
journal
journal
32447
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"