Development of a simplified densitometer for the determination of aflatoxins by thin-layer chromatography.
A simple, miniaturised and low power consuming (battery, fully semiconductor based) detector cell (SeBaDeC) was developed for the densitometric measurement of aflatoxins on TLC plates. A UV-light emitting diode (UV-LED) with a peak emission wavelength of 370 nm was used for fluorescence excitation, while a photo diode with a peak sensitivity of 440 nm in combination with a 418 nm cut-off filter was applied for detecting the fluorescence intensity. The resulting signal was further amplified by means of a commonly used operational amplifier integrated circuit (OA) and directly converted into a digital signal with a simple analogue-digital-converter (ADC). This signal was recorded at the serial (RS232) port of a portable PC and processed with a spreadsheet program. The software used for data recording is freeware and available in its source code, and the long lifetime of the UV-LED (up to 10 000 h) permits a maintenance free application of this device. This simplified device has shown to be able to detect concentrations of aflatoxins of 1 ng, thus offering a cheap and sensitive alternative to currently available TCL scanners.
Stroka
J
J
European Commission, Joint Research Centre, Institute for Health and Consumer Protection, Food Products and Consumer Goods Unit, Italy.
Anklam
E
E
D000348:Aflatoxins / Q000032:analysis*; D002855:Chromatography, Thin Layer / Q000379:methods*; D003720:Densitometry / Q000295:instrumentation*; D012984:Software; D013056:Spectrophotometry, Ultraviolet
D000348:Aflatoxins