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Over the past two decades, higher efficiencies have become the goal of most research organizations, and more so for high throughput synthesis. Consequently, there is an urgent need for an advanced purification approach to accommodate the large number of small molecules in a shorter turnaround time. To address this, an efficient and high throughput purification method was developed leveraging the superficially porous particle (SPP) column technology, which was optimized with respect to detector acquisition rate, flow rate, and gradient time. The experiments were performed using a sample mixture of six commercially available small molecules including Nicotinamide (NIC), 4-Amino benzophenone (ABP), Praziquantel (PRA), butyl‑4-hydroxybenzoate (BHB), Warfarin sodium (WAR), and Ibuprofen (IBU). The study outcomes were promising and exhibited a good separation of all six analytes with ∼83 % less turnaround time and ∼65 % less solvent consumption than the regular methods. Furthermore, it showed significant improvement in peak symmetry, capacity factor, and resolution for all six analytes and afforded superior chromatographic performance than the regular method with fully porous particle (FPP) columns. The study concludes that SPP columns provide cost-effective, eco-friendly, and high throughput purification of small molecules.

Phenolic compounds are frequently present in various natural products, and they can have different beneficial biological potentials. The most widely used method for determination of individual phenolic compounds is high-performance liquid chromatography (HPLC). In this paper, a method for simultaneous determination of 16 phenolic compounds (gallic acid, p-hydroxybenzoic acid, catechin, syringic acid, trans-cinnamic acid, hesperetin, naringenin, vanillic acid, benzoic acid, coumaric acid, resveratrol, chlorogenic acid, caffeic acid, rutin, quercetin, and kaempferol) on a core–shell column was developed. The separation method conducted on a standard ODS (250 mm) column was transferred to Poroshell column and optimized using non-ultra-high-performance liquid chromatography (UHPLC) apparatus. Phenolic compounds were separated fast and efficiently during 30-min analysis, and validation parameters were determined. The developed method was successfully applied on the analysis of phenolic content after direct injection of red wines from three different grape varieties. [ABSTRACT FROM AUTHOR]

Fruits of Silybum marianum (L.) Gaernt are the main source of taxifolin derived flavonolignans. Together, these molecules constitute a mixture called silymarin with many useful applications for cosmetic and pharmaceutic industries. Here, a validated method for the separation of the silymarin constituents has been developed to ensure precision and accuracy in their quantification. Each compound was separated with a high reproducibility. Precision and repeatability of the quantification method were validated according to the AOAC recommendations. The method was then applied to study the natural variability of wild accessions of S. marianum. Analysis of the variation in the fruits composition of these 12 accessions from Pakistan evidenced a huge natural diversity. Correlation analysis suggested a synergistic action of the different flavonolignans to reach the maximal antioxidant activity, as determined by cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays. Principal component analysis (PCA) separated the 12 accessions into three distinct groups that were differing from their silymarin contents, whereas hierarchical clustering analysis (HCA) evidenced strong variations in their silymarin composition, leading to the identification of new silybin-rich chemotypes. These results proved that the present method allows for an efficient separation and quantification of the main flavonolignans with potent antioxidant activities.

Barley (Hordeum vulgare L.) is a cereal crop that has been cultivated since ancient times. However, its interest as nutritional food and as food ingredient is relatively new. Thus, in this study, the phenolic compounds of eighteen different varieties of barley (4 waxy and 14 non-waxy) grown under the same agronomic conditions in the same experimental field have been determined by HPLC-DAD-MS. Two new methodologies were developed using new generation superficially porous HPLC columns with different stationary phases: C18 and pentafluorophenyl (PFP). Twelve free phenolic compounds and eight bound phenolic compounds could be identified in barley samples in less than 22min. The study of different method parameters showed that C18 column was more suitable for the analysis of phenolic compounds of barley. Hierarchical cluster analysis (HCA) was conducted in order to assess the different ability of the two different core shell HPLC columns in the discrimination between "waxy" and "non-waxy" varieties, and only HCA of C18 column could separate waxy and non-waxy genotypes. Significant differences in the content of phenolic compounds between waxy and non-waxy samples were found, being waxy barley samples the ones which presented higher content of free and bound phenolic compounds. Once the best discriminant HPLC column was established, principal component analysis (PCA) was applied and it was able to discriminate between "waxy" and "non-waxy" varieties; however it discriminated the barley samples based only in free phenolic compounds. Because of that, partial least squares discriminant analysis (PLS-DA) and Artificial Neural Networks (ANN) were carried out. PLS-DA and ANN permitted the classification of waxy and non-waxy genotypes from both free and bound phenolic compounds. [ABSTRACT FROM AUTHOR]

Fruits of Silybum marianum (L.) Gaernt are the main source of taxifolin derived flavonolignans. Together, these molecules constitute a mixture called silymarin with many useful applications for cosmetic and pharmaceutic industries. Here, a validated method for the separation of the silymarin constituents has been developed to ensure precision and accuracy in their quantification. Each compound was separated with a high reproducibility. Precision and repeatability of the quantification method were validated according to the AOAC recommendations. The method was then applied to study the natural variability of wild accessions of S. marianum. Analysis of the variation in the fruits composition of these 12 accessions from Pakistan evidenced a huge natural diversity. Correlation analysis suggested a synergistic action of the different flavonolignans to reach the maximal antioxidant activity, as determined by cupric ion reducing antioxidant capacity (CUPRAC) and ferric reducing antioxidant power (FRAP) assays. Principal component analysis (PCA) separated the 12 accessions into three distinct groups that were differing from their silymarin contents, whereas hierarchical clustering analysis (HCA) evidenced strong variations in their silymarin composition, leading to the identification of new silybin-rich chemotypes. These results proved that the present method allows for an efficient separation and quantification of the main flavonolignans with potent antioxidant activities. [ABSTRACT FROM AUTHOR]