Planar chromatographic super-hyphenations for rapid dereplication

Abstract

Analytical chemistry offers important tools that provide insight and step-by-step understanding. However, natural samples containing many thousands of different compounds are subject to natural variance which makes it complex for artificial intelligence and human understanding. Instead of the prevailing comprehensive separation/detection approach, a prioritization approach is discussed for dereplication that focuses on the most necessary to discover. It is extremely helpful to combine on the same surface two disciplines, i.e. chemistry for separation of mixtures and biology for detection of biological effects, to filter out and prioritize the important compounds that then need to be identified. Complex mixtures are separated in parallel with imaging high-performance thin-layer chromatography, detected non-targeted with planar multiplex bioassays to prioritize compounds and elute the important ones to orthogonal column chromatography−diode array detection−high-resolution mass spectrometry for further characterization. Super-hyphenations reduce thousands of compounds to a manageable number of important active compounds. Its potential lies not only in the prioritization of compounds, but also detection of unknown compounds that were not previously the focus of analysts. An image is worth a thousand words and an effect image even more so. On-surface multiplex bioassays enable the differentiation of opposing signals/effects of compounds in a complex natural sample, which only makes understanding possible. On-surface metabolization enables the study of any changes in the effects through digestion or de-/toxification (S9 liver system). By these new tools applied on the same surface, the mechanisms of action of complex mixtures can be better understood. The latest open-source 2LabsToGo system combines the chemistry and biology laboratory in a miniaturized system developed for wider use of this innovative technique.

Bioactivity Profiling and Quantification of Gastrodin in Gastrodia elata Cultivated in the Field versus Facility via Hyphenated High-Performance Thin-Layer Chromatography

“…Hyphenated HPTLC [ 45 ] and its miniaturization to an open-source 2LabsToGo system [ 54 ] is a straightforward, fast, and low-cost technique for the separation of complex mixtures. It contributes to more sustainable methods, analyzing all samples simultaneously with less consumption of chemical reagents.…”

“…For complex sample analysis, hyphenated high-performance thin-layer chromatography (HPTLC) is a versatile tool that can be used for simultaneous sample separation, allowing authenticity screening [ 27 , 28 , 29 , 30 , 31 , 32 ], non-target bioprofiling [ 33 , 34 , 35 , 36 ], as well as quantification of chemical marker compounds [ 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ] from a wide variety of samples, including foods, plants, and other natural products. The combination of multiple analytical steps and identification of bioactivity by the same workflow makes hyphenated HPTLC a very sustainable technique and allows complex mixtures, such as plant extracts, to be studied in parallel in a much faster and straightforward way [ 45 , 46 ].…”

Stability of Flavan-3-ols, Theaflavins, and Methylxanthines in 30 Industrial Green, Black, and White Tea (Camellia sinensis L.) Extracts Characterized via Liquid Chromatography Techniques

“…HPTLC was combined with enzymatic or biological planar assays to answer important questions regarding the bioactivity of the functional extracts. Such hyphenated HPTLC is a highly straightforward tool to find effects in complex samples [21][22][23][24][25]. Here, as an alternative method, HPTLC-UV/Vis was used for comparative quantification and for the verification of the obtained HPLC-DAD results via a second independent chromatographic method.…”

Will planar bioassays replace the prevalent in vitro assays?

“…planar chromatographic separation, and biology, i.e. toxicological detection) on the same surface yields meaningful and true results, if compared to the status quo 2 3 . First by this combination, the differentiation of opposing effects/responses is possible and important effects are not overlooked.…”