Dual-modal analysis of cis-diols in traditional Chinese medicine via boronic acid incorporated metal organic frameworks.

In this study, a boronic acid incorporated metal organic frameworks (inBA-MIL-100) were prepared via metal-ligand-fragment co-assembly strategy. The prepared frameworks can be served either as enrichment sorbent or SALDI-MS matrix for cis-diol containing molecules. Thus, a dual-modal analysis of cis-diols in traditional Chinese medicine has been established. Several significant advantages of the proposed strategy have been experimentally demonstrated, including high selectivity, high binding capacity (70 mg/g), good generality (5-250 µg/mL for HPLC based sample preparation, 10-500 ng/mL for SALDI-MS), high sensitivity (LOD: 180 ng/mL for HPLC based sample preparation, 5 ng/mL for SALDI-MS) and reliable quantification (RSD<3 % for HPLC based sample preparation, RSD<12 % for SALDI-MS) performance. Finally, the successful analysis of various cis-diols (active component and mycotoxin) in various Chinese traditional medicine was also achieved.

Structure-Assisted Boronic Acid Implanted Mesoporous Metal-Organic Frameworks for Specific Extraction of cis-Diol Molecules.

cis-Diol-containing molecules, an essential type of compounds in living organisms, have attracted intensive research interest from various fields. The analysis of cis-diol-containing molecules is still suffering from some drawbacks, including low abundance and abundant interference. Metal-organic frameworks (MOFs) have proven to be an ideal sorbent for sample preparation. However, most of the reported MOFs are mainly restricted to a microporous regime (pore size <2 nm), which greatly limits the application. Herein, a facile strategy is established to construction of boronate affinity MOFs via the postsynthetic ligand-exchange process. Owing to the fact that the ligand-exchange process was assisted by the structural integrity of the primitive metal-organic framework and the great compatibility of click chemistry, the obtained EPBA-PCN-333(Fe) is able to realize the maximum maintaining the porosity and crystallinity of the parent material. Several intriguing features of EPBA-PCN-333(Fe) (e.g., excellent selectivity, efficient diffusion, good accessibility, and size exclusion effect) are experimentally demonstrated via a series of cis-diol-containing molecules with different molecular sizes (small molecules, glycopeptides, and glycoproteins). The binding performance of EPBA-PCN-333(Fe) is evaluated by employing catechol as the test molecule (binding capacity: 0.25 mmol/g, LOD: 200 ng/mL). Finally, the real-world applications of EPBA-PCN-333(Fe) were demonstrated by the detection of nucleosides of human urine samples.

Magnetic dendritic mesoporous silica nanoparticles based integrated platform for rapid and efficient analysis of saccharides.

BACKGROUND: As an essential compound in living organism, saccharides have attracted enormous attentions from scientists in various fields. Understanding the distribution of saccharides in various samples is of great scientific importance. However, the low signal response and lack of specific recognition technology of saccharides and the complex matrix of samples make the analysis of saccharides a very challenge task. Thus, the development of a simple and straightforward strategy for the analysis of saccharides would represent a great contribution to the field. RESULTS: In this study, by employing the sulfonyl functionalized magnetic dendritic mesoporous silica nanoparticles as the substrate, we develop an integrated platform for analysis of saccharides. The construction of the platform mainly relied on multi-functional boronic acid, which serves as separation and derivation ligands at the same time. In the general procedure, the boronic acid is first immobilized onto the surface of substrate, then the selective enrichment of saccharides can be realized via boronate affinity separation. Finally, by the rational choice of the solution, we are able to elute the labelled complex (boronic acid-saccharide) from the substrate, which can be direct subjected to HPLC-UV analysis. The reliable precision (<15 %), accuracy (80-100 %), reproducibility (<10 %), improved sensitivity (20x) and limited time-consuming (down to minutes) of the proposed platform are experimentally demonstrated. SIGNIFICANCE AND NOVELTY: The successful quantification of different saccharides (alditols, glucose) in real samples is achieved. The proposed strategy is not only straightforward and fast, but also avoid the requirement of special equipment. With these attractive features, we believe that this strategy will greatly prompt the analysis of saccharides in various samples (eg. food, pharmaceutics and biosamples).