Read by QxMD icon Read

Analytical and Bioanalytical Chemistry

Markéta Machálková, Jan Schejbal, Zdeněk Glatz, Jan Preisler
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS) is a well-established method with a unique set of qualities including sensitivity, minute sample consumption, and label-free detection, all of which are highly desired in enzyme assays. On the other hand, the application of MALDI TOF MS is usually limited by high concentrations of MS-incompatible compounds in the reaction mixture such as salts or organic solvents. Here, we introduce kinetic and inhibition studies of β-secretase (BACE1), a key enzyme of the progression of Alzheimer's disease...
September 15, 2018: Analytical and Bioanalytical Chemistry
Raquel González de Vega, David Clases, María Luisa Fernández-Sánchez, Noemí Eiró, Luis O González, Francisco J Vizoso, Philip A Doble, Alfredo Sanz-Medel
MMP-11 is a member of the matrix metalloproteinase family (MMPs) which are overexpressed in cancer cells, stromal cells and the adjacent microenvironment. The MMP protein family encompasses zinc-dependent endopeptidases that degrade the extracellular matrix (ECM), facilitating the breakdown of the basal membrane and matrix connective tissues. This function is believed to be important in cancer development and metastasis. This paper investigated a gold nanoparticle-based immunohistochemical assay to visualise the distribution of MMP-11 in human breast cancer tissues from eight patients with and without metastases by employing laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)...
September 15, 2018: Analytical and Bioanalytical Chemistry
Kai Kysenius, Bence Paul, James B Hilton, Jeffrey R Liddell, Dominic J Hare, Peter J Crouch
Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) analysis of μ-droplets is becoming an attractive alternative for detecting and quantifying elements in biological samples. With minimal sample preparation required and detection limits comparable to solution nebulisation ICP-MS, μ-droplets have substantial advantages over traditional elemental detection, particularly for low volumes, such as aliquots taken from samples required for multiple independent biochemical assays, or fluids and tissues where elements of interest exist at native concentrations not suited to the necessary dilution steps required for solution nebulisation ICP-MS...
September 15, 2018: Analytical and Bioanalytical Chemistry
Hema Bhardwaj, Chandan Singh, R K Kotnala, Gajjala Sumana
Due to the similar electrochemical properties to graphene oxide (GO), graphene quantum dots (GQDs) are considered as a highly potential candidate for designing an electrochemical biosensor. In this report, GQDs were synthesized having an average diameter of 7 nm and utilized for the fabrication of an electrochemical immunosensor for the detection of food toxin, aflatoxin B1 (AFB1 ). An electrophoretic deposition technique was utilized to deposit the chemically synthesized GQDs onto indium tin oxide (ITO)-coated glass substrate...
September 14, 2018: Analytical and Bioanalytical Chemistry
Zhenping Liu, Yiyun Wang, Xuchu Wang, Weiwei Liu, Yibei Dai, Pan Yu, Zhaoping Liao, Ying Ping, Zhihua Tao
A molecular beacon (MB) is an oligonucleotide hybridization probe with a hairpin-shaped structure that leads to specific and instantaneous nucleic acid hybridization, enabling a variety of applications. However, integration of additional module sequences interferes with the performance of MBs and increases the complexity of sequence design. Herein, we develop and characterize a toehold integrated molecular beacon (ToMB) strategy for nucleic acid hybridization, where the reaction rate can be flexibly regulated by a target-induced MB conformational switch...
September 14, 2018: Analytical and Bioanalytical Chemistry
Christin Helmschrodt, Kathrin Schmidt, Sandra Bertulat, Laura Klein, Anke Finnah, Wolfgang Heuwieser, Angelika Richter
A robust liquid chromatography-tandem mass spectrometry method was developed and comprehensively validated for the quantification of cefquinome considering the changing matrix composition from bovine colostrum to raw milk. Sample preparation consisted of addition of isotopically labeled cefquinome internal standard prior to protein precipitation of 2 g colostrum or milk followed by solid-phase extraction. A wide concentration range from 1 to 5000 ng cefquinome per gram of colostrum or milk was quantified using a 3200 QTRAP tandem mass spectrometer in positive ionization mode with electrospray ionization...
September 14, 2018: Analytical and Bioanalytical Chemistry
Imanol Torre-Fdez, Julene Aramendia, Leticia Gomez-Nubla, Kepa Castro, Maite Maguregui, Silvia Fdez-Ortiz de Vallejuelo, Gorka Arana, Juan M Madariaga
The application of a non-destructive analytical procedure to characterise the mineral phases in meteorites is a key issue in order to preserve this type of scarce materials. In the present work, the Elephant Moraine 83227 meteorite, found in Antarctica in 1983 and originated from 4 Vesta asteroid, was analysed by micro-Raman spectroscopy, micro-energy-dispersive X-ray fluorescence and the structural and chemical analyser (Raman spectroscopy coupled with scanning electron microscopy-energy-dispersive spectroscopy) working in both point-by-point and image modes...
September 14, 2018: Analytical and Bioanalytical Chemistry
Adam T Woolley
No abstract text is available yet for this article.
September 14, 2018: Analytical and Bioanalytical Chemistry
Tingting Wang, Dan Luo, Zheyan Chen, Yining Qu, Xiuhua Ma, Jiannong Ye, Qingcui Chu, Dongping Huang
A novel capillary electrophoresis with laser-induced fluorescence detection method has been developed for the analysis of aldehyde metabolism biomarkers for oxidative stress in exhaled breath condensate (EBC), and fluorescein 5-thiosemicarbazide was used as a derivatization reagent. In a simple capillary zone electrophoresis mode, ten low molecular weight aldehydes (LMWAs) could be well separated within 30 min. The reaction efficiency was doubled by increasing sample solution pH and magnetic stirring, and the LODs of this method reached 0...
September 13, 2018: Analytical and Bioanalytical Chemistry
Bin Li, Ying Zhang, Junyue Ge, Kehui Liu, Ping Li
Appropriate sample preparation is pivotally important to obtain high-quality mass spectrometry imaging (MSI) data. Unlike mammalian tissues, preparation of cryosections from plant tissues for MSI measurement is quite challenging due to its intrinsic complex texture and cellular structure. This is especially true for leaf samples which are generally thin, water-rich, and fragile. In this work, a systematic study was performed, aiming to evaluate three embedding materials and five mounting approaches for matrix-assisted laser desorption ionization (MALDI) MSI of secondary metabolites in cross sections of the ginkgo leaf...
September 13, 2018: Analytical and Bioanalytical Chemistry
Thomas J Wenzel
No abstract text is available yet for this article.
September 13, 2018: Analytical and Bioanalytical Chemistry
Susana Campuzano
No abstract text is available yet for this article.
September 13, 2018: Analytical and Bioanalytical Chemistry
Yan-Qin Huang, Sha Fu, Yong-Sheng Wang, Jin-Hua Xue, Xi-Lin Xiao, Si-Han Chen, Bin Zhou
We certify that protamine-gold nanoclusters (PRT-AuNCs) synthesized by one-pot method exhibit peroxidase-like activity. The catalytic activity of PRT-AuNCs followed typical Michaelis-Menten kinetics and exhibited higher affinity to 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate compared to that of natural horseradish peroxidase. Meanwhile, we found that Hg(II) could dramatically and selectively enhance the peroxidase-like activity of PRT-AuNCs, and the enhanced mechanism by Hg(II) was demonstrated to be generation of the cationic Au species and the partly oxidized Au species (Auδ+ ) by Hg2+ -Au0 /Au+ interaction...
September 13, 2018: Analytical and Bioanalytical Chemistry
Shasha Jiao, Pengyan Liu, Ying Liu, Rubing Zou, Ying Zhao, Yihua Liu, Guonian Zhu, Yirong Guo
In this study, heterologous indirect competitive enzyme-linked immunosorbent assay (icELISA) was introduced into the screening of hybridomas for the development of broad-specific monoclonal antibodies (mAbs) against organophosphorus (OP) pesticides. After immunization, two formats of icELISA based on the homologous hapten antigen and four heterologous hapten antigens were conducted for hybridoma screening. Two mAbs 2G6 and 7B2 with good recognition toward three OP pesticides (parathion, methyl-parathion, and fenitrothion) were produced...
September 12, 2018: Analytical and Bioanalytical Chemistry
Chun Y Wong, Jorge Martinez, Hani Al-Salami, Crispin R Dass
Therapeutic proteins are administered subcutaneously because of their instability in the gastrointestinal tract. Current research suggests that polymeric-based nanoparticles, microparticles and liposomes are ideal nanocarriers to encapsulate proteins for disease management. In order to develop a successful drug delivery system, it is crucial to determine drug release profile and stability. However, the non-active excipients in polymeric formulations can influence the quantification of proteins in analytical techniques...
September 11, 2018: Analytical and Bioanalytical Chemistry
Sheying Dong, Qi Lou, Guiqi Huang, Jingjun Guo, Xiaohong Wang, Tinglin Huang
The method based on the dispersive solid-phase extraction (DSPE) by novel molybdenum disulfide modified with carbon dot (MoS2 /CD) composite combined with high-performance liquid chromatography (HPLC) was developed for the determination of three brominated flame retardants (BFRs), including tetrabromobisphenol A (TBBPA), tetrabromobisphenol A bisallylether (TBBPA-BAE), and tetrabromobisphenol A bis(2,3-dibromopropyl ether) (TBBPA-BDBPE). Owing to the stacked planar structure and large surface area of MoS2 , a large number of CDs can be easily loaded on the surface of MoS2 ...
September 10, 2018: Analytical and Bioanalytical Chemistry
Alireza Banazadeh, Seth Williamson, Masoud Zabet, Ahmed Hussien, Yehia Mechref
More than 50% of all known proteins are glycosylated, which is critical for many biological processes such as protein folding and signal transduction. Glycosylation has proven to be associated with different mammalian diseases such as breast and liver cancers. Therefore, characterization of glycans is highly important to facilitate a better understanding of the development and progression of many human diseases. Although matrix-assisted laser desorption ionization-mass spectrometry (MALDI-MS) offers several advantages such as ease of operation and short analysis times, however, due to the complexity of glycan structures and their low ionization efficiency, there are still challenges that need to be addressed to achieve sensitive glycan analysis...
September 8, 2018: Analytical and Bioanalytical Chemistry
Júlia Pereira Rodrigues, Shamina Saiyara Prova, Luiz Alberto Beraldo Moraes, Demian Rocha Ifa
The discovery of new secondary metabolites is a challenge to biotechnologists due to the emergence of superbugs and drug resistance. Knowledge about biodiversity and the discovery of new microorganisms have become major objectives; thus, new habitats like extreme ecosystems have become places of interest to research. In this context, caatinga is an unexplored biome. The ecosystem caatinga is a rich habitat for thermophilic microbes. Its high temperature and dry climate cause selective microbes to flourish and become established...
September 8, 2018: Analytical and Bioanalytical Chemistry
Patrick Harte, Marco Evertz, Timo Schwieters, Marcel Diehl, Martin Winter, Sascha Nowak
In this study, laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) was applied to previously aged carbonaceous anodes from lithium ion batteries (LIBs). The electrodes were treated by cyclic aging in a lithium ion cell set-up with LiNi0.5 Mn1,5 O4 (LNMO) cathodes and hard carbon (HC)/mesocarbon microbead (MCMB) anodes. An inhomogeneous transition metal deposition pattern could be induced by replacing the spacer in a standard coin cell set-up with a washer. The inhomogeneity pattern matched the dimension of the washer depicted by the hole in the center...
September 7, 2018: Analytical and Bioanalytical Chemistry
Hind El Hadri, Julien Gigault, Jiaojie Tan, Vincent A Hackley
Applications of asymmetrical flow field-flow fractionation (AF4) continue to expand rapidly in the fields of nanotechnology and biotechnology. In particular, AF4 has proven valuable for the separation and analysis of particles, biomolecular species (e.g., proteins, bacteria) and polymers (natural and synthetic), ranging in size from a few nanometers to several micrometers. The separation of non-spheroidal structures (e.g., rods, tubes, etc.) with primary dimensions in the nanometer regime, is a particularly challenging application deserving of greater study and consideration...
September 7, 2018: Analytical and Bioanalytical Chemistry
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"