Analyst Blog

Three HOT articles from Analyst covering sampling bias, copper sensing and PDMS functionalisation for a photnoic lab-on-a-chip device.  All articles are free to read until 8th April.

Michael H. Ramsey and co-workers from Sussex and London describe a new method for estimating the uncertainty of analytical measurements caused by bias in sampling. Improved evaluation of measurement uncertainty from sampling by inclusion of between-sampler bias using sampling proficiency testing Michael H. Ramsey, Bastiaan Geelhoed, Roger Wood and Andrew P. Damant Analyst, 2011, Advance Article DOI: 10.1039/C0AN00705F
	Based on the Cu(I)-catalyzed alkyne–azide cycloaddition reaction, a novel ultra-high sensitive and selective ECL sensor for Cu(II) was developed and is reported in this paper from Guonan Chen and co-workers from Fuzhou University in China. Development of ultra-high sensitive and selective electrochemiluminescent sensor for copper(II) ions: a novel strategy for modification of gold electrode using click chemistry Suyan Qiu, Sen Gao, Xi Zhu, Zhenyu Lin, Bin Qiu and Guonan Chen Analyst, 2011, Advance Article DOI: 10.1039/C0AN00846J
César Fernández-Sánchez and co-workers from Spain and Germany report on a comparative study of different approaches for the selective immobilisation of biomolecules on the surface of poly(dimethylsiloxane) (PDMS). The motivation of this work is to set a robust and reliable protocol for the easy implementation of a biosensor device in a PDMS-based photonic lab-on-a-chip (PhLoC). Selective functionalisation of PDMS-based photonic lab on a chip for biosensing Bergoi Ibarlucea, César Fernández-Sánchez, Stefanie Demming, Stephanus Büttgenbach and Andreu Llobera Analyst, 2011, Advance Article DOI: 10.1039/C0AN00941E

In this HOT communication, Zongxiu Nie and his team from China and Taiwan report the development of a miniature cylindrical ion trap mass spectrometer (CIT-MS) equipped with laser-induced acoustic ionization and a charge detector.  They describe its use in the measurement of the total dry mass of red blood cells after calibration with standard polystyrene beads.

The novel miniature CIT-MS has, compared with a previous lab scale quadrupole ion trap mass spectrometer (QIT-MS), smaller volume, simpler ion trap fabrication and overall instrument construction, requires a lower trapping voltage and has reduced weight, power and cost. The new miniaturized instrument has potential for applications in field-portable, biological and aerosol analysis.

Interested in knowing more? Read for free until April 4th.

Characterization of bioparticles using a miniature cylindrical ion trap mass spectrometer operated at rough vacuum
Zhiqiang Zhu, Caiqiao Xiong, Gaoping Xu, Hao Liu, Xiaoyu Zhou, Rui Chen, Wen-Ping Peng and Zongxiu Nie
Analyst, 2011, Advance Article
DOI: 10.1039/C0AN00911C

This study describes the development of an effective detection probe for the visualisation of organophosphorous pesticides based on the rare combination of both colorimetric and fluorescent output.

Haibing Li and co-workers at the Central China Normal University developed a versatile yet simple strategy for the fabrication of a highly selective and sensitive fenamithion probe based on Rhodamine B modified silver nanoparticles. They propose and prove a novel amino-containing analyte-induced etching mechanism to explain their results. This system allows prompt on-site and real-time detection of the pesticide, fenamithion, in real vegetable and water samples, with high sensitivity and excellent anti-disturbance ability.

Interested in knowing more? Read the article for free until March 1st.

Dual-signal fenamithion probe by combining fluorescence with colorimetry based on Rhodamine B modified silver nanoparticles
Zhimin Cui, Cuiping Han and Haibing Li
Analyst, 2011, Advance Article
DOI: 10.1039/C0AN00617C

Scientists from Korea have immobilised a reactive antibody onto the surface of a microfluidic sensor to allow immunosensing with minimal steps to analyse a fluctuating analyte concentration continuously. They found that the antibody showed rapid kinetic properties in both the association and dissociation reactions, and also had a high binding affinity.

When monitoring the analyte level in the sample, the binder was able to be continuously recycled without interrupting the analytical conditions, according to the researchers.  The continuous immunosensor displayed characteristics that were suitable for in vitro disease diagnosis so could be used as a novel analytical tool for a direct online clinical decision, they added.

Minimum-step immuno-analysis based on continuous recycling of the capture antibody
Hyun-Kyu Cho, Sung-Min Seo, Il-Hoon Cho, Sung-Ho Paek, Dong-Hyung Kim and Se-Hwan Paek
Analyst, 2011, Advance Article
DOI: 10.1039/C0AN00811G

Chemiluminescence has been extensively used for analytical purposes but very limited research has been devoted to the theoretical basics of the technique. In this study by Paul S. Francis and co-workers in Australia, a combination of electrochemical, spectroscopic and computational techniques are used to explore the properties of ruthenium complexes designed for coupling with other molecules or surfaces for electrochemiluminescence applications. 

Interested in knowing more?  Read for free here until 21st March!

Simultaneous control of spectroscopic and electrochemical properties in functionalised electrochemiluminescent tris(2,2′-bipyridine)ruthenium(II) complexes
Gregory J. Barbante, Conor F. Hogan, David J. D. Wilson, Naomi A. Lewcenko, Frederick M. Pfeffer, Neil W. Barnett and Paul S. Francis
Analyst, 2011, Advance Article
DOI: 10.1039/C0AN00952K

In this study, Xing-guo Chen and co-workers in Lanzhou, China, established a new flow injection–capillary electrophoresis (FI–CE) system in which a cross-H-channel interface was constructed for coupling FI with CE. Compared with typical FI–CE, the advantages of this new technique include lower sample solution requirement, shorter analysis time, and higher sensitivity.

Interested in knowing more?  Read the full text here; free until 18^th March!

A novel cross-H-channel interface for flow injection-capillary electrophoresis to reduce sample requirement and improve sensitivity
Hua-dong Zhu, Wenjuan Lü, Hong-hong Li, Yan-hua Ma, Shao-qiang Hu, Hong-li Chen and Xing-guo Chen
Analyst, 2011, Advance Article
DOI: 10.1039/C0AN00592D