INTRODUCTION: Quinotoxine is an alkaloid that was originally obtained synthetically by Pasteur. Its presence in quinine bark was subsequently established. However, numerous biological tests with this alkaloid dispelled all suspicions about its toxicity. Despite this, the suffix -toxin in its trivial name has remained unchanged. In the 1970s, the appearance of this alkaloid was registered on the pharmaceutical market. Over the years, a number of its derivatives, which featured a powerful antibacterial effect, also appeared. Whether it has been regarded as a synthetic precursor or a drug, the potential of the alkaloid in question is undeniable. Therefore, every single aspect of its analysis is fully justified.
AIM: The aim of this article is to provide a much handier method for the qualitative analysis of the alkaloid quinotoxine.
MATERIALS AND METHODS: A strategy developed by Kehrmann was applied for the qualitative analysis of quinotoxine; this strategy targets the alkaloid’s inherent piperidine residue. All tests were conducted using standard laboratory glassware. The authenticity of the studied alkaloid was confirmed by infrared and ultraviolet visible (UV-Vis) analysis.
RESULTS: Immediately following the introduction of the studied alkaloid to the bromine-phenothiazine solution, the appearance of a characteristic blue coloration was registered. To rule out the possibility of a false-positive result, the alkaloid quinine was also analyzed in parity. No indication of any analytical reflex to the quinuclidine-containing alkaloid was observed. The main characteristic of this test, the limit of detection (LOD), was also established. Its value was determined to be 7.5 micrograms.
CONCLUSION: This communiqué can be perceived as a first attempt to analyze the piperidine residue of the alkaloid quinotoxine. Given that other available methods target the quinoline residue, which is common to this alkaloid class, the presented test may represent an optimal choice for achieving the intended goal. Moreover, given the feasibility of the presented test, it can be easily implemented and can be performed by student pharmacists.
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