For effective drug quality control and detection of falsified and substandard medicines in developing
countries, there is an urgent need to develop reliable, rapid, and inexpensive analytical methods. In this
work, a methodology combining a low-cost near infrared transmission spectrophotometer with
chemometrics and sample analysis in solution has been applied to develop qualitative and quantitative
methods to analyze metronidazole in various formulations. To achieve this, calibration and validation
solution samples of metronidazole at different concentrations were prepared. The qualitative method
consisted of building a model based on a data driven soft independent modeling of class analogy using
metronidazole samples at the concentration of 100 mg L−1 as the target class. The built model allowed
a satisfactory identification of metronidazole at the target concentration and a clear discrimination of the
excipient mixture and metronidazole samples at other concentration levels and related active
pharmaceutical ingredients used to mimic falsified and substandard drugs. The quantitative method was
based on a partial least squares regression model allowing the quantification of metronidazole in the
concentration range of 50–125 mg L−1
. The regression model was fully validated according to the
accuracy profile methodology. Both qualitative and quantitative methods were successfully employed to
analyze various metronidazole tablet samples collected in Burkina Faso. The obtained outcomes
underline the feasibility of using these economically accessible portable spectrophotometers as a first
line screening tool for drug quality control and detection of falsified and substandard drugs in developing
countries.

Metronidazole, spectrometry, Infra red, Chemometry, Burkina Faso