"The technique uses field-effect transistors (electronic devices that contain an electrode
 source and a draining electrode connected to a transducer) based on carbon nanotubes and
 with Candida albicans-specific antibodies", Raquel A. Villamizar, lead author of the study
 said.

 The Candida samples, which can be obtained from blood, serum or vaginal secretions, are
 placed directly on the biosensor, where the interaction between antigens and antibodies  changes the electric current of the devices. This change is recorded and makes it possible to
 measure the amount of yeast present in a sample.

 "Thanks to the extraordinary charge transference properties of the carbon nanotubes, the
 fungus detection process is direct, fast, and does not require the use of any marker", remarks
 Villamizar, who is co-author of a study that provides details of the biosensor and was
 published recently in the journal Sensors and Actuators B: Chemical.

 To date, conventional diagnosis of Candida has been carried out using microbial cultures,
 serological tests, PCR molecular biology techniques (polymerase chain reactions used to
 amplify DNA), or immunoassays such as ELISA (Enzyme Linked Inmunoabsorbent Assay).

 These techniques require long analysis times and sometimes give rise to false positives and
 negatives. ELISA also requires the use of markers (compounds that must be added to detect
 the presence of yeast by fluorescence and other techniques).

 The new carbon nanotubes biosensor, however, "makes it possible to improve some of the
 quality parameters of the traditional methods, for example the speed and simplicity of
 measurements, and it is an alternative tool that could be used in routine sample analysis",
 explains Villamizar.

 The researcher adds that by using this biosensor "it will be possible in future to obtain a rapid
 diagnosis of infection with this pathogen, which will help to ensure administration of the
 correct prophylactic treatments".

 The Candida albicans fungus exists naturally in the skin, mouth, the mucous membranes lining
 the digestive tract, and the respiratory and genitourinary systems. This yeast can cause
 anything from simple mycosis of the skin to complicated cases of candidiasis. It is much more
 commonly found in patients suffering from immunodeficiency, tumours, diabetes and
 lymphomas, among other diseases.

 Courtesy of http://www.sciencedaily.com