Open Access

Bernd Spangenberg, Andrea Seigel, Alexandra Schröck, Rebekka Hauser

• We present a video-densitometric quantification method for the pain killer known as diclofenac and ibuprofen. These non-steroidal anti-inflammatory drugs were separated on cyanopropyl bonded plates using CH2Cl2, methanol, cyclohexane (95+5+40, v/v) as mobile phase. The quantification is based on a bio-effective-linked analysis using vibrio fischeri bacteria. Within 10 minutes a CCD-cameraWe present a video-densitometric quantification method for the pain killer known as diclofenac and ibuprofen. These non-steroidal anti-inflammatory drugs were separated on cyanopropyl bonded plates using CH2Cl2, methanol, cyclohexane (95+5+40, v/v) as mobile phase. The quantification is based on a bio-effective-linked analysis using vibrio fischeri bacteria. Within 10 minutes a CCD-camera registers the white light of the light-emitting bacteria. Diclofenac and ibuprofen effectively suppress the bacterial light emission which can be used for quantification within a linear range of 10 to 2000 ng. The detection limit for ibuprofen is 20 ng and the limit of quantification 26 ng per zone. Measurements were carried out using a 16-bit ST-1603ME CCD camera with 1.56 megapixels [from Santa Barbara Instrument Group, Inc., Santa Barbara, USA]. The range of linearity covers more than two magnitudes because the extended Kubelka-Munk expression is used for data transformation [1]. The separation method is inexpensive, fast and reliable. Ibuprofen is named after its chemical description: iso-butyl-propanoic phenolic acid. Both pain killers are world-widein use and both substances are stable in aqueous solution. Both substances are mainly excreted in the urine.…