142
Views
0
CrossRef citations to date
0
Altmetric
Articles

Simultaneous determination of 11 nootropic substances potentially adulterated in dietary supplements for improving brain function using ultra-performance liquid chromatography and liquid chromatography–quadrupole-time-of-flight mass spectrometry

ORCID Icon, ORCID Icon, , , &
Pages 797-811 | Received 14 Mar 2023, Accepted 02 Jun 2023, Published online: 23 Jun 2023
 

Abstract

Recently, the demand for improved brain function and concentration has increased in the dietary supplement market. However, to artificially enhance their pharmacological efficacy, dietary supplements may be illegally adulterated with unauthorised substances. Therefore, we developed a rapid and accurate method to simultaneously determine 11 nootropic substances using an ultra-high-performance liquid chromatography (UPLC) system equipped with a photodiode array (PDA) detector. In addition, sample preparation procedures were semi-optimised for various types of matrices, including solid (hard capsule, tablet, powder, and pill) and liquid (oil and extract) samples. The method was validated to determine the limit of detection (LOD), limit of quantification (LOQ), method detection limit (MDL), method quantitation limit (MQL), specificity, linearity, precision, accuracy, recovery, stability, and matrix effects. The validation results satisfied international validation guideline requirements. To test the applicability of the method, 55 real samples advertised as effective brain health, memory, and cognition supplements were analysed. Among the real samples, vinpocetine (2.483 and 7.296 µg/g), and kavain (69–44.056 µg/g) were detected. In addition, the detected compounds were confirmed by comparing their fragmentation patterns with those of the reference standards using liquid chromatography–quadrupole-time-of-flight mass spectrometry (LC-QTOF/MS). In conclusion, the UPLC-PDA method not only rapidly and accurately quantifies illegal nootropics but also enables the pre-emptive investigation and identification of 11 nootropic substances in illegal dietary supplements to protect public health.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

Data supporting the findings of this study are available in the supplementary material of this article.

Additional information

Funding

This study was supported by a grant [Number: 21201MFDS306] from the Ministry of Food and Drug Safety of Korea in 2021.

Reprints and Corporate Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

To request a reprint or corporate permissions for this article, please click on the relevant link below:

Academic Permissions

Please note: Selecting permissions does not provide access to the full text of the article, please see our help page How do I view content?

Obtain permissions instantly via Rightslink by clicking on the button below:

If you are unable to obtain permissions via Rightslink, please complete and submit this Permissions form. For more information, please visit our Permissions help page.