| 摘要 |
Sensor devices for electrolytic analysis of liquid media, comprising a working electrode coated with an aminoacid polymer (preferably poly-lysine on platinum), advantageously with a diffusion-lowering barrier layer of an applied or deposited thin porous or permeable layer of organic polymer or inorganic material superimposed upon it which allows analytes to pass through. The barrier coating stabilises the poly-aminoacid coating against dislodgement by acidic media and the poly-aminoacid/covering barrier combination gives a sensor having enough stability to be heat-sterilised, good pH independence and selectivity with minimal interference by other components, and long user life. Preferred barrier materials are PVC, (which can be applied from solution, e.g. dip-coating) and diamond-like carbon ("DLC"), preferably 5 mu m thick or less. The electro-analytical procedure preferred is pulsed amperometric detection ("PAD"). The sensors are especially effective for ethanol determination, and applicable to monitoring and measurement of fermentation media with reduced interference by any sugars present. |
