Analyst Blog

Detecting bacteria using magnetic nanoparticles

Jeon et al., Analyst, 2012, Advance Article

Nowadays, the standard method for detecting bacteria in food samples is through the use of conventional cell culture and immunoassays using fluorescent and radioactive tags. While this method is very accurate, it does not allow real-time, on-site analysis. From Pohang University of Science and Technology, Korea, comes the work of Sangmin Jeon and coworkers who have developed a simple, and rapid method for the detection of pathogenic bacteria in foods using magnetic nanoparticles and TiO₂ nanocrystals. To read how they have accomplished this, click on the title below.

A facile and sensitive detection of pathogenic bacteria using magnetic nanoparticles and optical nanocrystal probes
Jinmyoung Joo, Changyong Yim, Donghoon Kwon, Jaejin Lee, Hwa Hui Shin, Hyung Joon Cha and Sangmin Jeon
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35369E

Colorimetric determination of hypochlorite

Yang et al., Analyst, 2012, Advance Article

Xiurong Yang and colleagues from the Changchun Institute of Applied Chemistry, China, have made a colorimetric method using gold nanoparticles to detect hypochlorite (OCl^–) in water. The assay can be performed in two easy steps and could possibly help with environmental monitoring of OCl⁻/HOCl in waters sanitized by chlorine or hypochlorite compounds. Click on the link below to read more about their research.

Colorimetric determination of hypochlorite with unmodified gold nanoparticles through the oxidation of a stabilizer thiol compound
Jia Zhang,  Xiaolei Wang and Xiurong Yang
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35239G

Analyzing biological tissue at a molecular level

Chen and Yao et al., Analyst, 2012, Advance Article

Huanwen Chen and Zhong-Ping Yao from the East China Institute of Technology and The Hong Kong Polytechnic University, respectively, have together with colleagues been working on a method of direct ionization followed by mass spectrometry to analyze plant and animal tissue at the molecular level at ambient conditions. Click on the title below to read more about their method.

Direct ionization of biological tissue for mass spectrometric analysis
Bin Hu, Ying-Han Lai, Pui-Kin So, Huanwen Chen and Zhong-Ping Yao
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN16223G

Monitoring Parkinson’s disease with implantable microelectrodes

Chen et al., Analyst, 2012, Advance Article

Parkinson’s disease is a neurodegenerative disorder that is characterized by the progressive depletion of dopamine (DA). There are currently several treatments that attempt to replace this depletion. As a result, accurately measuring the levels of DA in the brain has become very important. Jia-Jin Jason Chen from the National Cheng Kung University, Taiwan, and colleagues have designed implantable DA sensing microelectrodes. To read more about their work click on the link below.

Microelectrodes with gold nanoparticles and self-assembled monolayers for in vivo recording of striatal dopamine
Tien-Chun Tsai, Chun-Xian Guo, Huan-Zhang Han, Yu-Ting Li, Ying-Zu Huang, Chang-Ming Li and Jia-Jin Jason Chen
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN16306C

Goodacre et al., Analyst, 2012, Advance Article

This month we have a HOT paper from Editorial Board member Duncan Graham. Together with Royston Goodacre and colleagues from the University of Manchester, the University of Strathclyde and Manchester Metropolitan University,  they have developed a fast and cost-effective method for the synthesis of substrates used in SERS using galvanic displacement. Click on the title below to read more.

The optimisation of facile substrates for surface enhanced Raman scattering through galvanic replacement of silver onto copper
Samuel Mabbott, Iain A. Larmour, Vladimir Vishnyakov, Yun Xu, Duncan Graham and Royston Goodacre
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35323G

Xu et al., Analyst, 2012, Advance Article

Imagine analyzing a single nanoparticle? That’s what Xiao-Hong Nancy Xu and her co-workers in the USA at Old Dominion University have been doing. They have development a single-NP plasmonic microscopy and spectroscopy and ultrasensitive in vivo assay which they are using to study transport and toxicity of single silver nanoparticles on embryonic development.

Single nanoparticle spectroscopy for real-time in vivo quantitative analysis of transport and toxicity of single nanoparticles in single embryos
Kerry J. Lee, Prakash D. Nallathamby, Lauren M. Browning, Tanvi Desai, Pavan K. Cherukuri and Xiao-Hong Nancy Xu
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35293A

Paul S. Francis from Deakin University, Australia, and colleagues from Australia and the USA have studied osmium complexes that contain phenanthroline, diphosphine and diarsine ligands and assessed their potential as chemiluminescence reagents. Osmium complexes do have some advantages over their ruthenium counterparts. The larger crystal field strength of the heavy metal raises the energy of the non-emissive d–d states. This in turn reduces thermal deactivation of the metal-to-ligand charge transfer (MLCT) states, creating greater photostability.

Francis et al., Analyst, 2012, Advance Article

Click here to read more about these interesting complexes.

Chemiluminescence from osmium(II) complexes with phenanthroline, diphosphine and diarsine ligands
Elizabeth M. Zammit, Gregory J. Barbante, Brenden Carlson, Egan H. Doeven, Neil W. Barnett, Conor F. Hogan, Mark M. Richter and Paul S. Francis
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35446B

A new biosensor that uses a target-induced DNAzyme cascade with catalytic and molecular beacons (CAMB) to fluorescently detect mercury(II) ions in water has been designed by a team from China. Yongxi Zhao from Xi’an Jiaotong University and colleagues tested the biosensor on river water samples with satisfactory results. Click on the title below to read more.

Amplified fluorescence detection of mercury(II) ions (Hg²⁺) using target-induced DNAzyme cascade with catalytic and molecular beacons
Lin Qi, Yongxi Zhao, Hui Yuan, Kai Bai, Yue Zhao, Feng Chen, Yanhua Dong and Yayan Wu
Analyst, 2012, Advance Article
DOI: 10.1039/C2AN35437C