THE OPTICAL MOLECULAR ANALYSIS OF THE PHARMACEUTICAL PREPARATIONS USING OF THE OFFICE FLATBED SCANNER: COLORIMETRY AND PHOTOMETRY

In recent years there has been a trend in using of various household optical devices – cameras, smartphones and other devices for chemical analysis. They are able to measure the amount of radiant energy passing through color filters mounted on the CCD, and to present the resulting information in digital form. The use of such a comparatively cheap device is available for the pharmaceutical analysis as well as for other tasks. It should be noted that the analytical signal sensitivity, the noise level, the range of linearity of the response function of the detector is very mediocre. Meanwhile, the change in the approach to the selection of the conditions of the signal can significantly improve the metrological characteristics of measurement results and to enhance the analytical capabilities of these devices. The most convenient equipment for the implementation of the new paradigm is ordinary office flatbed scanner with a slide adapter cause of its size, form factor, ability to ensure the stability of the measurement conditions. This paper describes the design and principles of using office flatbed scanner for colorimetric and photometric determination of active ingredients in pharmaceutical preparations. To optimize the conditions of the colorimetric analysis, we proposed special wedgeshaped for ditch liners. The possibilities of the developed optical analyzer are demonstrated on the example of the determination of acetylsalicylic acid in a drug Cardiomagnyl®. We measured absorption spectra and constructed calibration curves to determine methylorange in solutions of different acidity to demonstrate the capabilities of the photocolorimetry based on the flatbed scanner. All measurements are duplicated on registered dual-beam spectrophotometer Hitachi U-2900 (Japan) to assess the effectiveness of the developed approaches.