Analyst Blog

Scientists in the Netherlands have developed and tested a new method that uses Raman spectroscopy to quickly identify harmful bacteria in drinking water. This could prevent contaminated drinking water from making people ill by detecting deadly bacteria before it ever reaches the tap.

Many of the standard methods used to test water quality rely on selective plating and enzyme activity tests which take a long time to get results. ‘The bottleneck between collection and results is because microbes need time to grow, or nucleic acids need time to be processed,’ says Jack van de Vossenberg, from the KWR Watercycle Research Institute, who led the research.

To read the full article please visit Chemistry World.

Identification of bacteria in drinking water with Raman spectroscopy
Jack van de Vossenberg, Heli Tervahauta, Kees Maquelin, Carola H. W. Blokker-Koopmans, Marijan Uytewaal-Aarts, Dick van der Kooij, Annemarie van Wezel and Bram van der Gaag  
Anal. Methods, 2013, Accepted Manuscript
DOI: 10.1039/C3AY40289D

Duncan Graham is Professor of chemistry at the University of Strathclyde, UK. He has recently been named as the next Chair of the Editorial Board for Analyst, and will start this role in 2014. His research areas include nucleic acid chemistry and synthetic chemistry for bioanalysis. Currently he is working on functionalised metallic nanoparticles that can be used for the diagnosis and treatment of disease.

What motivated you to specialise in SERS (surface enhanced Raman spectroscopy)?

Duncan Graham

 To read the full article please visit Chemistry World.

The first baseline analysis of healthy human breath brings closer the possibility of routine diagnosis of disease from exhaled air. Over 70 volatile organic compounds (VOCs) have been identified by Pawel Mochalski and colleagues from the Austrian Academy of Sciences, who used headspace solid phase microextraction (HS-SPME) to pre-concentrate samples prior to their analysis by GC-MS.

Breath analysis for healthcare is a hot topic, with the ultimate goal being a device that can identify an illness from a single breath at your doctor’s surgery. Although this is still some way off, breath chemistry is used currently to monitor some conditions. Exhaled nitric oxide is used to keep tabs on asthma and tuberculosis (TB), while hydrocarbons can warn of the impending rejection of a transplanted heart.

To read the full article please visit Chemistry World.

 Blood and breath levels of selected volatile organic compounds in healthy volunteers
Paweł Mochalski, Julian King, Martin Klieber, Karl Unterkofler, Hartmann Hinterhuber, Matthias Baumann and Anton Amann Analyst, 2013,138, 2134-2145
DOI: 10.1039/C3AN36756H

A mass-spectrometry technique that can characterise and spatially resolve the metabolites produced by bacteria could lead to a better understanding of how different microbes interact with each other, and how their chemistry could be harnessed industrially.

Of the thousands of chemical metabolites produced by bacteria, only a tiny fraction are accessible to the organic chemist using traditional synthetic techniques. Microbes can defend against attack with their own herbicides, pesticides and antibiotics, and encourage plants and animals that are beneficial to their survival by producing stimulants or substances that inhibit pathogens.

To read the full article please visit Chemistry World.

Spatially resolved analysis of glycolipids and metabolites in living Synechococcus sp. PCC 7002 using nanospray desorption electrospray ionization
Ingela Lanekoff, Oleg Geydebrekht, Grigoriy E. Pinchuk, Allan E. Konopka and Julia Laskin
Analyst, 2013,138, 1971-1978
DOI: 10.1039/C3AN36716A

An immunosensor that recognises the specific immune response to gluten, generated by coeliac disease sufferers, has been developed by scientists in Spain and Portugal.

Coeliac disease is a chronic intolerance to gluten – a protein found in wheat, barley, rye and oats – that leads to inflammation of the small intestine. This can cause malnutrition and diarrhoea in sufferers.

To read the full article please visit Chemistry World.

An electrochemical deamidated gliadin antibody immunosensor for celiac disease clinical diagnosis
Marta M. P. S. Neves ,  María Begoña González-García ,  Henri P. A. Nouws and Agustín Costa-García
Analyst, 2013, Advance Article
DOI: 10.1039/C3AN36728B

Currently the only way to identify whether a suspicious lump is something to be concerned about is to have it removed surgically and then examined by histological review. But a new diagnostic technique based around Raman spectroscopy could provide a faster diagnosis without the need for such invasive procedures.

Raman Spectroscopy has been used previously to distinguish benign and metastatic axillary lymph nodes (in the breast) and mediastinal nodes (in the oesophagus). Now Nicholas Stone and co-workers at the University of Exeter, UK have now applied the technique to distinguish between different cancerous conditions of lymph nodes in the head and neck.

Doctors coudl soon be using Raman spectroscopy to peform 'optical biopsies' of tumours © Shutterstock

 To read the full article please visit Chemistry World.

Discrimination between benign, primary and secondary malignancies in lymph nodes from the head and neck utilising Raman spectroscopy and multivariate analysis
Gavin Rhys Lloyd, Linda E. Orr, Jonathan Christie-Brown, Keith McCarthy, Simon Rose, Michael Thomas and Nicholas Stone
Analyst, 2013, Advance Article
DOI: 10.1039/C2AN36579K

Antibiotics are used regularly for treating bacterial infections, but there is currently no quick and simple test to determine the most effective type or dose of antibiotic for a specific patient infection. As a result, it’s estimated that around 30% of all antibiotic prescriptions are not the optimum choice. This can lead to the formation of drug-resistant bacteria, delayed recovery, and in some cases death from an infection.

Tests for the most appropriate antibiotic choice are performed for life-threatening patient infections. However, microbes have to be grown on agar plates from a very small patient sample which delays results for a few days. Hiroaki Suzuki et al have designed a microfluidic device that is able to determine the most effective antibiotic treatment in just 12 hours.

To read the full article please visit Chemistry World.

A microfluidic microbial culture device for rapid determination of the minimum inhibitory concentration of antibiotics
Rika Takagi ,  Junji Fukuda ,  Keiji Nagata ,  Yutaka Yawata ,  Nobuhiko Nomura and Hiroaki Suzuki
Analyst, 2013,138, 1000-1003
DOI: 10.1039/C2AN36323B