title: Towards point of care testing forC. difficileinfection by volatile profiling, using the combination of a short multi-capillary gas chromatography column with metal oxide sensor detection.
abstract: Rapid volatile profiling of stool sample headspace was achieved using a combination of short multi-capillary chromatography column (SMCC), highly sensitive heated metal oxide semiconductor (MOS) sensor and artificial neural network (ANN) software. For direct analysis of biological samples this prototype offers alternatives to conventional GC detectors and electronic nose technology. The performance was compared to an identical instrument incorporating a long single capillary column (LSCC). The ability of the prototypes to separate complex mixtures was assessed using gas standards and homogenised in house 'standard' stool samples, with both capable of detecting more than 24 peaks per sample. The elution time was considerably faster with the SMCC resulting in a run time of 10 minutes compared to 30 minutes for the LSCC. The diagnostic potential of the prototypes was assessed using 50C. difficilepositive and 50 negative samples. The prototypes demonstrated similar capability of discriminating between positive and negative samples with sensitivity and specificity of 85% and 80% respectively.C. difficileis an important cause of hospital acquired diarrhoea, with significant morbidity and mortality around the world. A device capable of rapidly diagnosing the disease at the point of care would reduce cases, deaths and financial burden.
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: N D
authors.initials: ND
authors.lastname: McGuire
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: R J
authors.initials: RJ
authors.lastname: Ewen
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: B
authors.initials: B
authors.lastname: de Lacy Costello
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: C E
authors.initials: CE
authors.lastname: Garner
authors.affiliation: Institute of Translational Medicine, University of Liverpool, Liverpool, United Kingdom.
authors.forename: C S J
authors.initials: CS
authors.lastname: Probert
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: K
authors.initials: K
authors.lastname: Vaughan
authors.affiliation: Institute of Biosensing Technology, University of the West of England, Bristol, United Kingdom.
authors.forename: N M
authors.initials: NM
authors.lastname: Ratcliffe
keywords: Clostridium difficile; artificial neural network; gas chromatography; gastro-intestinal; metal oxide semiconductor; multicapillary column; sensor; stool; volatile