Analyst Blog

Detection of cardiac troponin with a surface acustive wave immunosensor

Youn-Suk Choi and Soo Suk Lee from the Samsung Advanced Institute of Technology, Republic of Korea, have developed a point of care diagnostic test for cardiac troponin I (cTnI).

The researchers fabricated a bubble-free microfluidics device based on a gold-nanoparticle immunoassay and a surface acoustic wave immunosensor. The authors highlight a limit of detection of  6.7 pg mL-1 as a clinically relevant result and a first for centrifugally-based microfluidic devices. In this work, the researchers developed the device for the detection of cTnI, a biomarker for acute myocardial infarction for which rapid analysis would be beneficial for patient prognosis. The group is now extending studies to alternative systems.

To read more about the current results, access this Analyst HOT article clicking on the link below. This paper will be free to read for the next 10 days.

A centrifugally actuated point-of-care testing system for the surface acoustic wave immunosensing of cardiac troponin I
Woochang Lee ,  Jaeyeon Jung ,  Young Ki Hahn ,  Sang Kyu Kim ,  Yeolho Lee ,  Joonhyung Lee ,  Tae-Han Lee ,  Jin-Young Park ,  Hyejung Seo ,  Jung Nam Lee ,  Jin Ho Oh ,  Youn-Suk Choi and Soo Suk Lee
Analyst, 2013,138, 2558-2566
DOI: 10.1039/C3AN00182B

Enzyme electrodes for glucose biosensing

Glucose oxidase (GOx) is responsible for breaking down glucose and produces a detectable secondary signal used in a variety of biological assays. The primary electrical response from this catalytic process is difficult to detect because of the distance of the signal from within the enzyme to the electrode. To overcome these limitations, Jingquan Liu and researchers at the Qingdao University, China, have developed an enzyme-based electrode with pyrene functionalized GOx, which self assembles onto graphene sheets. The large surface area and high conductivity of graphene sheets enhance the electron transfer from the GOx via interaction with the pyrene, down to the electrode. In addition, increasing alternating layers of the pyrene-GOx and graphene enhances the biocatalytic activity in glucose solutions.

To know more about this research, please access the link below. This paper will be free to read until April 12^th.

Graphene bridged enzyme electrodes for glucose biosensing application
Jingquan Liu ,  Na Kong ,  Aihua Li ,  Xiong Luo ,  Liang Cui ,  Rui Wang and Shengyu Feng
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36929C

Take a look at these selected HOT articles just published in Analyst. Analysis of skin damage due to solar radiation, a new technique enabling “condom brand spectroscopic fingerprint” and the development of a testing system for the surface acoustic wave immunosensing of cardiac troponin I are among the HOT topics reported in Analyst. All the papers below will be free for you to read until April 12^th. Have a read now!

Raman spectroscopic mapping for the analysis of solar radiation induced skin damage
S. M. Ali ,  F. Bonnier ,  K. Ptasinski ,  H. Lambkin ,  K. Flynn ,  F. M. Lyng and H. J. Byrne
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36617K

Probing site-exclusive binding of aqueous QDs and their organelle-dependent dynamics in live cells by single molecule spectroscopy
Chaoqing Dong ,  Basudev Chowdhury and Joseph Irudayaraj
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36906D

Spectroscopic imaging based approach for condom identification in condom contaminated fingermarks
Robert Bradshaw ,  Rosalind Wolstenholme ,  Leesa Susanne Ferguson ,  Chris Sammon ,  Kerstin Mader ,  Emmanuelle Claude ,  Robert D. Blackledge ,  Malcolm R. Clench and Simona Francese
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN00195D

Surface acoustic wave immunosensing of cardiac troponin I

Highly sensitive grating coupler-based surface plasmon-coupled emission (SPCE) biosensor for immunoassay
Jong Seol Yuk ,  Ernest F. Guignon and Michael A. Lynes
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN00135K

Graphene bridged enzyme electrodes for glucose biosensing application
Jingquan Liu ,  Na Kong ,  Aihua Li ,  Xiong Luo ,  Liang Cui ,  Rui Wang and Shengyu Feng
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36929C

A centrifugally actuated point-of-care testing system for the surface acoustic wave immunosensing of cardiac troponin I
Woochang Lee ,  Jaeyeon Jung ,  Young Ki Hahn ,  Sang Kyu Kim ,  Yeolho Lee ,  Joonhyung Lee ,  Tae-Han Lee ,  Jin-Young Park ,  Hyejung Seo ,  Jung Nam Lee ,  Jin Ho Oh ,  Youn-Suk Choi and Soo Suk Lee
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN00182B

Suwan Jayasinghe, Analyst, 2013, 138, 2215-2223

The Issue 8 of Analyst is now online. Take a look at our beautiful covers and discover all about the latest research in the field of analytical chemistry.

The outside front cover introduces the interesting minireview written by Suwan Jayasinghe from the University College London, featuring the most recent tools developed to generate fibers, scaffolds and membranes for application in regenerative biology and medicine. According to the author, these structures have important implications in both the laboratory and clinical settings, as they mimic the native extracellular matrix and can be used to directly reconstruct a three-dimensional functional tissue.

Cell electrospinning: a novel tool for functionalising fibres, scaffolds and membranes with living cells and other advanced materials for regenerative biology and medicine
Suwan N. Jayasinghe
Analyst, 2013,138, 2215-2223
DOI: 10.1039/C3AN36599A

Chen at al., Analyst, 2013, 138, 2392-2397

Our inside front cover features the work of Zhong-Ping Yao and colleagues from the Hong Kong Polytechnic University, who reported a new tool for detection and quantitation of ketamine and norketamine. In this study, drugs are detected in urine and oral fluids using wooden-tip electrospray ionization mass spectrometry (WT-ESI-MS). Compared to other methods, this approach has the advantage of little sample preparation and no chromatographic separation.

Rapid detection and quantitation of ketamine and norketamine in urine and oral fluid by wooden-tip electrospray ionization mass spectrometry
Pui-Kin So ,  Tsz-Tsun Ng ,  Haixing Wang ,  Bin Hu and Zhong-Ping Yao
Analyst, 2013,138, 2239-2243
DOI: 10.1039/C3AN36641C

Along with our two new covers, we have some HOT articles for you to enjoy. To know more, click on the links below. All these papers will be free to read until April 4^th.

Near-infrared to near-infrared upconverting NaYF4:Yb3+,Tm3+ nanoparticles-aptamer-Au nanorods light resonance energy transfer system for the detection of mercuric(II) ions in solution
Hong-Qi Chen ,  Fei Yuan ,  Shao-Zhen Wang ,  Juan Xu ,  Yi-Yan Zhang and Lun Wang
Analyst, 2013,138, 2392-2397
DOI: 10.1039/C3AN36921H

Determination of nitrite and glucose in water and human urine with light-up chromogenic response based on the expeditious oxidation of 3,3′,5,5′-tetramethylbenzidine by peroxynitrous acid
Jia Zhang ,  Cheng Yang ,  Chuanxia Chen and Xiurong Yang
Analyst, 2013,138, 2398-2404
DOI: 10.1039/C3AN00080J

Corona discharge radical emission spectroscopy: a multi-channel detector with nose-type function for discrimination analysis
Yunfei Tian ,  Peng Wu ,  Xi Wu ,  Xiaoming Jiang ,  Kailai Xu and Xiandeng Hou
Analyst, 2013,138, 2249-2253
DOI: 10.1039/C3AN36859A

Reversible binding and quantification of heparin and chondroitin sulfate in water using redox-stable biferrocenylene SAMs
Kun Chen and Michael Schmittel
Analyst, 2013,138, 2405-2410
DOI: 10.1039/C3AN36781A

Porphyrin-anion transmembrane transport using PAMPA

The Parallel Artificial Membrane Permeability Assay (PAMPA) is a popular tool used in pharmaceutical industry to screen new drugs and evaluate their permeability across membranes. Vladimir Kral and colleagues from the Institute of Chemical Technology Prague, propose a low cost approach for screening transmembrane transport of supermolecular complexes using PAMPA. According to the authors, inorganic anions bound to a porphyrin receptor can be efficiently transported across membranes.

To know more about the study, please click on the link below. This paper will be free to read until April 4^th.

Study of receptor mediated selective anion transmembrane transport using parallel artificial membrane permeability assay
Lenka Veverková ,  Kamil Záruba and Vladimír Král
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36760F

Photomicrograph of a nifedipine particle and photermal spectra

Duncan Craig from the University College London and collaborators from the Universities of Cambridge and East Anglia have applied Photothermal Infrared Microscopy (PTMS) to study drug degradation.

A combination of Fourier Transform Infrared Spectroscopy (FT-IR) and a modification of atomic force microscopy, PTMS, was used to pick up microparticles of a drug known for its photo-instability and analyse its degradation by changes in the FT-IR spectrum after exposure to light.  In this HOT new Analyst paper the researchers not only show the application of this new technique but discuss some limitations and areas for future development.

To know more about the study, please access the link below. This paper will be free to read until April 4^th.

Analysis of single particle photodegradation using photothermal infrared microspectroscopy
Jonathan G. Moffat ,  Mark D. Eddleston ,  Peter S. Belton ,  William Jones and Duncan Q. M. Craig
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36686C

Streptavidin-biotin as example of receptor-ligand binding in TERS

Targeted nanoparticles and Tip-Enhanced Raman spectroscopy (TERS) can be used to investigate biomolecular interactions, suggests a new study published in Analyst.

Hao Wang and Zachary Schultz  at the University of Notre Dame, USA, examine the effect of nanoparticle probe size on detected TERS signal obtained from different functionalised gold nanoparticles, and compare the observed TERS signals from aggregated nanoparticle SERS. TERS is usually employed in the analysis of carbon nanotubes, dye molecules, and semiconductors, but recently it has also been used for detection of molecules in biological samples.
According to the authors, the new methodology suggests a way to enhance TERS signals associated with protein receptors in biological systems that cannot be isolated on a metallic surface.

To read more about this research, please access the link below. This paper will be free to read until March 18^th .

The chemical origin of enhanced signals from tip-enhanced Raman detection of functionalized nanoparticles
Hao Wang and Zachary D. Schultz
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36898J

Visualizing latent fingerprints on stailess steel substrates

Check out our latest hot articles just published in Analyst!

They include a wide variety of topics such as nanospray desorption electrospray ionization for detection of microbial metabolites, near-infrared fluorescent probes for sensing nitroreductase in an aqueous medium, and visualization of latent fingerprint on stainless steel surfaces by electrochemiluminescence. These papers will be free to read until March 25th. Take a look NOW!

Non-destructive enhancement of latent fingerprints on stainless steel surfaces by electrochemiluminescence
Linru Xu ,  Yan Li ,  Yayun He and Bin Su
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN00110E

A novel near-infrared fluorescent probe for selectively sensing nitroreductase (NTR) in an aqueous medium
Youmin Shi ,  Sichun Zhang and Xinrong Zhang
Analyst, 2013, 138, 1952-1955 
DOI: 10.1039/C3AN36807F

Near-infrared fluorescent probe for selectively sensing nitroreductase in an aqueous medium

Label-free selective impedimetric detection of Cu2+ ions using catalytic DNA
Cristina Ocaña ,  Natalia Malashikhina ,  Manel del Valle and Valeri Pavlov
Analyst, 2013,138, 1995-1999 
DOI: 10.1039/C3AN36778A

Chitosan-capped silver nanoparticles as a highly selective colorimetric probe for visual detection of aromatic ortho-trihydroxy phenols
Zhaohui Chen ,  Xiaodan Zhang ,  Haiyan Cao and Yuming Huang
Analyst, 2013, e
DOI: 10.1039/C3AN36905F

Hairpin oligonucleotides anchored terbium ion: a fluorescent probe to specifically detect lead(II) at sub-nM levels
Yueteng Wei ,  Ru Liu ,  Yaling Wang ,  Yuliang Zhao ,  Zhifang Cai and Xueyun Gao
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36795A

Schematic interaction between Ce3+ and phosphate

Guang-Li Wang and co-workers, from the Jiangnan University, China, have developed an assay to detect the level of phosphate in water. 

Ce³⁺ ions are used to aggregate citrate-capped silver nanoparticles with cysteine-capped quantum dots, thereby causing efficient quenching of the fluorescence signal.  However, when phosphate is introduced to the system it interacts with the Ce³⁺ ions causing the quenched aggregates to redisperse and switching the fluorescent signal from “off” to “on”.  This work has potential applications for the environmental analysis of groundwater.

To read more about this work, please access this Analyst HOT article below. It will be free to read until March 8th.

Novel switchable sensor for phosphate based on the distance-dependant fluorescence coupling of cysteine-capped cadmium sulfide quantum dots and silver nanoparticles
Guang-Li Wang ,  Huan-Jun Jiao ,  Xiao-Ying Zhu ,  Yu-Ming Dong and Zai-Jun Li
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36878E

Schematic picture of a hybrid instrument correlating different spectral imaging modes

Scientists use chemical imaging to address a variety of issues visualising the arrangement of atoms, the content of single cells or the colourless gases released into Earth’s atmosphere by cities of kilometre scale. Many analytical techniques have been developed to date and researchers are now interested in combining the different imaging modalities to increase and improve the information gathered from imaging experiments.

In this new Critical Review just published in Analyst Paul Bohn and his group at the University of Notre Dame, USA, explore all the latest imaging techniques and introduce the new area of Raman imaging and mass spectrometry in the field of correlated imaging.

To know more, please access the full article below. It will be free to read until March 8th.

Correlated imaging – a grand challenge in chemical analysis
Rachel Masyuko ,  Eric J. Lanni ,  Jonathan V. Sweedler and Paul W. Bohn
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36416J