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Boronic acids are known for their specific affinity to glycoproteins via cis-diol groups of glycan under alkaline conditions. Here in this work, we have synthesized a boronic acid based porous polymer in a single step in less than 4 h using environmentally safe solvents. The presence of functional boron–oxygen (B–O) of 3-(acrylamido) phenyl boronic acid within the polymer was confirmed by FT-IR spectroscopy and Energy-dispersive X-ray spectroscopy of FE-SEM. Under optimized binding buffer conditions (0.2 M phosphate buffer; pH 8 without salt), compared to 6 and 9.6 mg of 3-(acrylamido) phenyl boronic acid per 58 mg of polymer, the polymer with 4 mg of boronic acid has captured maximum amount of the model glycoprotein i.e. transferrin (Trf). The boronate polymer has displayed good adsorption capacities for the three glycoproteins (IgG (50 mg/g), Trf (25 mg/g) and ovalbumin (OVA; 35 mg/g)) as compared to non-glycoprotein (myoglobin; 2 mg/g polymer) within 120 min. Trf was eluted using 100 mM sorbitol (pH 8), whereas IgG required harsh elution buffer i.e. 100 mM ammonium acetate (pH 3). Both IgG and Trf were selectively captured from a model mixture comprising of 10-fold low IgG and Trf as compared to myoglobin and from a complex sample such as human plasma as well. Two widely known egg white glycoproteins (ovotransferrin (OVT) and OVA) and 13 human plasma glycoproteins (identified using QToF-MS) were selectively captured from egg white sample and human plasma respectively. [ABSTRACT FROM AUTHOR]

Incorporating nanoparticles into injectable hydrogels is a well-known technique for improving the mechanical properties of these materials. However, significant differences in the mechanical properties of the polymer matrix and the nanoparticles can result in localized stress concentrations at the polymer–nanoparticle interface. This situation can lead to problems such as particle–matrix debonding, void formation, and material failure. This work introduces boronic acid/boronate ester dynamic covalent bonds (DCBs) as energy dissipation sites to mitigate stress concentrations at the polymer–nanoparticle interface. Once boronic acid groups were immobilized on the surface of SiO2 nanoparticles (SiO2-BA) and incorporated into an alginate matrix, the nanocomposite hydrogels exhibited enhanced viscoelastic properties. Compared to unmodified SiO2 nanoparticles, introducing SiO2 nanoparticles with boronic acid on their surface improved the structural integrity and stability of the hydrogel. In addition, nanoparticle-reinforced hydrogels showed increased stiffness and deformation resistance compared to controls. These properties were dependent on nanoparticle concentration. Injectability tests showed shear-thinning behavior for the modified hydrogels with injection force within clinically acceptable ranges and superior recovery. [ABSTRACT FROM AUTHOR]

We demonstrated that the combination of a Pd(0) catalyst and a water‐soluble TPPMS ligand has high activity for the direct arylation of readily available allylic alcohols in the Tsuji–Trost type cross‐coupling. Various organoboron reagents can be applied, enabling rapid access to the corresponding arylated products with a wide range of functional group tolerance. Kinetic studies revealed a first‐order rate dependence for the allylic alcohol, boronic acid, CsF and Pd(0)/TPPMS concentrations. A Hammett study found a slightly positive ρ value of 0.79, suggesting that a partial negative charge is generated on the aromatic ring of the aryl boronate in the rate‐determining transmetalation step. Based on several control experiments, we concluded that the transmetalation employing CsF would proceed via the oxo‐palladium mechanism. [ABSTRACT FROM AUTHOR]

The long-lived room-temperature phosphorescence (RTP) originating from thiophene boronate polyvinyl alcohol (PVA) has enabled the creation of metal-ion-responsive RTP films doped with spirolactam ring-containing rhodamine 6G (1). In this study, RTP-active PVA films, namely, TDB@PVA and ATB@PVA, were prepared through boronate esterification of thiophene-2,5-diboronic acid (TDB) and 5-acetylthiophene-2-boronic acid (ATB) with the diol units of PVA. The delayed emission properties were evaluated, revealing an emission band at 477 nm with a turquoise afterglow for TDB@PVA and at 510 nm with a green afterglow for ATB@PVA after UV light irradiation ceased. The photophysical properties were assessed using TD-DFT and DFT calculations at the B3LYP/cc-pVDZ level. N-(rhodamine-6G)lactam dye with a salicylimine unit (1) was doped into the RTP-based PVA films, producing a multicolored afterglow upon the addition of metal ions. This phenomenon is explained by a triplet-tosinglet Förster-type resonance energy transfer process from the cross-linked thiophene boronate in PVA to the metal-ion-activated colored form of 1. This photophysical feature finds applicability in encryption techniques. Notably, the reversible metal-ligand coordination of 1 in the PVA system enabled a write/erase information process. [ABSTRACT FROM AUTHOR]

An innovative supramolecular architecture is reported for bienzymatic glucose biosensing based on the use of a nanohybrid made of multi-walled carbon nanotubes (MWCNTs) non-covalently functionalized with a Schiff base modified with two phenylboronic acid residues (SB-dBA) as platform for the site-specific immobilization of the glycoproteins glucose oxidase (GOx) and horseradish peroxidase (HRP). The analytical signal was obtained from amperometric experiments at − 0.050 V in the presence of 5.0 × 10−4 M hydroquinone as redox mediator. The concentration of GOx and HRP and the interaction time between the enzymes and the nanohybrid MWCNT–SB-dBA deposited at glassy carbon electrodes (GCEs) were optimized through a central composite design (CCD)/response surface methodology (RSM). The optimal concentrations of GOx and HRP were 3.0 mg mL−1 and 1.50 mg mL−1, respectively, while the optimum interaction time was 3.0 min. The bienzymatic biosensor presented a sensitivity of (24 ± 2) × 102 µA dL mg−1 ((44 ± 4) × 102 µA M−1), a linear range between 0.06 mg dL−1 and 21.6 mg dL−1 (3.1 µM–1.2 mM) (R2 = 0.9991), and detection and quantification limits of 0.02 mg dL−1 (1.0 µM) and 0.06 mg dL−1 (3.1 µM), respectively. The reproducibility for five sensors prepared with the same MWCNT–SB-dBA nanohybrid was 6.3%, while the reproducibility for sensors prepared with five different nanohybrids and five electrodes each was 7.9%. The GCE/MWCNT–SB-dBA/GOx-HRP was successfully used for the quantification of glucose in artificial human urine and commercial human serum samples. [ABSTRACT FROM AUTHOR]

Chemometrics is a useful technique to analyze large amounts of data collected to generate insights and predict behaviors, being applied to boronate supramolecules. Boronic acid-based dynamic covalent bond with diols and catechols is a great advantage for multivariate analysis, involving calibration and prediction of the % ee of enantiomeric analytes using chiral boronates. Chemometrics-assisted quantitative structure-property relationship analysis has also been applied to room-temperature phosphorescence behavior of boronate assemblies. This review highlights the effectiveness of chemometrics in experimental material chemistry. [ABSTRACT FROM AUTHOR]

Microbial infections are a global health challenge often treated with antibiotics, but their overuse can lead to antibiotic resistance. To address this, there is a need for more efficient personal protective equipment (PPE) with novel antimicrobial techniques. One such technique involves using carbon dots (CDs) to create self-disinfecting fabrics. This study focused on synthesizing phenylboronic-acid-functionalized piperine-based carbon dots (PBA-PPCDs) and boronic acid carbon dots (BACDs) as potential antimicrobial agents. The materials were successfully synthesized using a hydrothermal method and characterized using various techniques to confirm the size, charge, fluorescence properties, and inner morphology of the CDs. The CDs showed bactericidal activity against gram-positive and gram-negative bacteria, with potent inhibition in growth especially in the presence of simulated sunlight. The antibacterial properties of the CDs were tested on cellulose discs, demonstrating strong adherence and significant inhibition of bacterial cells. The cytotoxicity studies showed that these CDs, at concentrations up to 0.1 mg/mL, and the CD-modified fibers are benign to mammalian cells, emphasizing their safety for human use. Overall, the study concluded that PBA-PPCDs and BACDs are promising candidates for modifying fibers and inducing antimicrobial activity in fabrics made of cellulose fibers.Article highlights: New self-disinfecting fabrics kill bacteria with light-activated carbon dots, no harsh chemicals needed. Self-disinfecting fabrics fight bacteria, reduce antibiotic use, and slow superbug growth. Safe and effective: Carbon dot fabrics harmless to humans, promising for PPE. [ABSTRACT FROM AUTHOR]

Abstract Surface display of functional groups with specific reactivity around living cells is an emerging, low cost and highly eco-compatible technology that serves multiple applications, ranging from basic biochemical studies to biomedicine, therapeutics and environmental sciences. Conversely to classical methods exploiting hazardous organic synthesis of precursors or monovalent functionalization via genetics, here we perform functional decoration of individual living microalgae using suitable biocoatings based on polydopamine, a melanin-like synthetic polymer. Here we demonstrate the one-pot synthesis of a functional polydopamine bearing phenylboronic units which can decorate the living cell surfaces via a direct ester formation between boronic units and surface glycoproteins. Furthermore, biosorption of fluorescent sugars on functionalized cell membranes is triggered, demonstrating that these organic coatings act as biocompatible soft shells, still functional and reactive after cell engineering.

Selective detection of reactive oxygen species (ROS) is vital for studying their role in brain diseases. Fluorescence probes can distinguish ONOO− species from other ROS; however, their selectivity toward ONOO− species depends on the ONOO− recognition group. Aryl‐boronic acids and esters, which are common ONOO− recognition groups, are not selective for ONOO− over H2O2. In this study, we developed a diaminonaphthalene (DAN)‐protected boronic acid as a new ONOO− recognition group that selectively reacts with ONOO− over H2O2 and other ROS. Three DAN‐protected boronic acid (DANBA)‐based fluorophores that emit fluorescence over visible to near‐infrared (NIR) regions, Cou‐BN, BVP‐BN, and HDM‐BN, and their aryl‐boronic acid‐based counterparts (Cou‐BO, BVP‐BO, and HDM‐BO), were developed. The DANBA‐based probes exhibited enhanced selectivity toward ONOO− over that of their control group, as well as universality in solution assays and in vitro experiments with PC12 cells. The NIR‐emissive HDM‐BN was optimized to delineate in vivo ONOO− levels in mouse brains with Parkinson's disease. This DAN‐protected boronic acid belongs to a new generation of recognition groups for developing ONOO− probes, and this strategy could be extended to other common hydroxyl‐containing dyes to detect ONOO− levels in complex biological systems and processes. [ABSTRACT FROM AUTHOR]

Objective: Boron structures play a crucial role in biological treatments due to their unique chemical properties. They are used in pharmaceuticals for their potential as enzyme inhibitors and as anti-inflammatory agents. Boron-containing compounds are also explored in drug delivery systems, leveraging their ability to cross cell membranes effectively. Additionally, boron-based materials are studied for their applications in biomaterials, such as wound healing and tissue engineering, highlighting their diverse applications in biological treatments. Methods: The study aims to elucidate the biological properties of catechin, a natural phenolic compound, by modifying it with phenylboronic acid. The Catechin-based boronic compound (CBC) was synthesized. The antioxidant and enzyme activity were studied. Histopathological experiments to vital organs and molecular docking studies were also conducted. Results and Discussion: The (CBC) showed meaningful antioxidant and enzyme activity when compared to standards. The effect of the (CBC) on tissues was demonstrated by in vivo experiments. Histopathological evaluation of vital organs in male Sprague Dawley rats was demonstrated by Hematoxylin–Eosin staining. The study has supported the antioxidant property of (CBC), also has a natural origin based on its structure. Besides, the antiurease and antityrosinase activities of catechin were tested for the first time. Furthermore, in silico approaches also supported the acceptable biological activity results that were experimentally examined. The interactions of AChE, BChE, urease, and tyrosinase enzymes with the (CBC) were investigated theoretically via molecular docking, and the binding parameter values were also shared. The (CBC) demonstrated radical scavenging activity. The in vivo experiments on rats were carried out and the (CBC) showed no negative effects on the vital organs. It was seen that the experimental results were in good agreement with the theoretical calculations. Conclusions: The analysis of the crystal structures of AChE, BChE, urease, and tyrosinase enzymes in relation to the compound (CBC) yielded striking results, highlighting the compound's promising potential as a therapeutic agent. [ABSTRACT FROM AUTHOR]

Herein, we investigated hydrogels composed of boronic-acid-functionalized alginate and blended with polyvinyl alcohol (PVA) of different molecular weights to control the release of metoclopramide hydrochloride as a function of pH and shear stress. The functionalization of alginate introduced dynamic covalent bonding and pH-responsive properties that can modulate network connectivity. The study investigated the viscoelastic properties of the hydrogels, their drug release profiles, and their responsiveness to changes in pH and shear forces. The results showed that a higher PVA molecular weight and alkaline pH conditions increased hydrogel viscosity and stiffness due to a more stable and interconnected network structure than acidic pH. Metoclopramide release revealed that the hydrogels exhibited pH-responsive drug release behavior. The drug was more readily released under acidic conditions due to the instability of sp2-hybridized boronate ester bonds. The influence of shear forces on the release of metoclopramide was also investigated at shear rates of 1, 10, and 100 s−1, revealing their effect on matrix stiffening. Research shows that AlgBA/PVA hydrogels have unique properties, such as dynamic covalent bonding, that make them sensitive to external mechanical forces. This sensitivity makes them ideal for applications where physiological conditions trigger drug release. [ABSTRACT FROM AUTHOR]

The sensitivity of immunoassays is generally limited by the low signal reporter/recognition element ratio. Nanomaterials serving as the carriers can enhance the loading number of signal reporters, thus improving the detection sensitivity. However, the general immobilization strategies, including direct physical adsorption and covalent coupling, may cause the random orientation and conformational change in proteins, partially or completely suppressing the enzymatic activity and the molecular recognition ability. In this work, we proposed a strategy to load recognition elements of antibodies and enzyme labels using boronic acid-modified metal-organic frameworks (MOFs) as the nanocarriers for signal amplification. The conjugation strategy was proposed based on the boronate ester interactions between the carbohydrate moieties in antibodies and enzymes and the boronic acid moieties on MOFs. Both enzymes and MOFs could catalyze the oxidation of 3,3′ ,5,5′ - tetramethylbenzidine (TMB) by H2O2, therefore achieving dual signal amplification. To indicate the feasibility and sensitivity of the strategy, colorimetric immunoassays of prostate specific antigen (PSA) were performed with boronic acid-modified Cu-MOFs as peroxidase mimics to catalyze TMB oxidation and nanocarriers to load antibody and enzyme (horseradish peroxidase, HRP). According to the change in the absorbance intensity of the oxidized TMB (oxTMB), PSA at the concentration range of 1~250 pg/mL could be readily determined. In addition, this work presented a site-specific and oriented conjugation strategy for the modification of nanolabels with recognition elements and signal reporters, which should be valuable for the design of novel biosensors with high sensitivity and selectivity. [ABSTRACT FROM AUTHOR]

Nanoclusters for fluorescence detection are generally comprised of rare and expensive noble metals, and the nanoclusters based on more affordable transition metal have attracted increasing attention. This study designed a ratiometric fluorescent probe to detect dopamine (DA), an important neurotransmitter. With carbon dots encapsulated within silica (CDs@SiO2) as the reference, the emitted reference signal was almost unchanged due to the protection of inert silicon shell. Meanwhile, copper nanoclusters modified with 3-aminophenyl boronic acid (APBA-GSH-CuNCs) provided the sensing signal, in which the phenylboric acid could specifically recognize the cis-diol structure of DA, and caused the fluorescence quenching by photoinduced electron transfer. This dual emission ratiometric fluorescent probe exhibited high sensitivity and anti-interference, and was able to selectively responded to DA with a linear range of 0–1.4 mM, the detection limit of 5.6 nM, and the sensitivity of 815 mM−1. Furthermore, the probe successfully detected DA in human serum samples, yielding recoveries ranging from 92.5% to 102.7%. Overall, this study highlights the promising potential of this ratiometric probe for detecting DA. [ABSTRACT FROM AUTHOR]

The wide use of boronic compounds, especially boronic acids and benzoxaboroles, in virtually all fields of chemistry is related to their specific properties. The most important of them are the ability to form cyclic esters with diols and the complexation of anions. In both cases, the equilibrium of the reaction depends mainly on the acidity of the compounds, although other factors must also be taken into account. Quantification of the acidity (pKa value) is a fundamental factor considered when designing new compounds of practical importance. The aim of the current work was to collect available values of the acidity constants of monosubstituted phenylboronic acids, critically evaluate these data, and supplement the database with data for missing compounds. Measurements were made using various methods, as a result of which a fast and reliable method for determining the pKa of boronic compounds was selected. For an extensive database of monosubstituted phenylboronic acids, their correlation with their Brønsted analogues—namely carboxylic acids—was examined. Compounds with ortho substituents do not show any correlation, which is due to the different natures of both types of acids. Nonetheless, both meta- and para-substituted compounds show excellent correlation. From a practical point of view, acidity constants are best determined from the Hammett equation. Computational approaches for determining acidity constants were also analyzed. In general, the reported calculated values are not compatible with experimental ones, providing comparable results only for selected groups of compounds. [ABSTRACT FROM AUTHOR]

Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of EA would determine its efficacy. Therefore, the accurate analysis of EA content can provide more information for the scientific consumption of EA-rich foods and cosmetics. Nevertheless, the analysis of EA in these samples is challenging due to the low concentration level and the presence of interfering components with high abundance. Molecularly imprinted polymers are highly efficient pretreatment materials in achieving specific recognition of target molecules. However, the traditional template molecule (EA) could not be absolutely removed. Hence, template leakage continues to occur during the sample preparation process, leading to a lack of accuracy in the quantification of EA in actual samples, particularly for trace analytes. In addition, another drawback of EA as an imprinting template is that EA possesses poor solubility and a high price. Gallic acid (GA), called dummy templates, was employed for the synthesis of MIPs as a solution to these challenges. The approach used in this study was boronate affinity-based oriented surface imprinting. The prepared dummy-imprinted nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((4.89 ± 0.46) × 10−5 M), high binding capacity (6.56 ± 0.35 mg/g), fast kinetics (6 min), and low binding pH (pH 5.0) toward EA. The reproducibility of the dummy-imprinted nanoparticles was satisfactory. The dummy-imprinted nanoparticles could still be reused even after six adsorption–desorption cycles. In addition, the recoveries of the proposed method for EA at three spiked levels of analysis in strawberry and pineapple were 91.0–106.8% and 93.8–104.0%, respectively, which indicated the successful application to real samples. [ABSTRACT FROM AUTHOR]

Tetrodotoxin (TTX) is a representative natural toxin causing pufferfish food poisoning, which is especially prominent in East and Southeast Asia, including Japan. TTX has been analyzed through post-column derivatization high-performance liquid chromatography (HPLC), ion-pair LC-MS(/MS), and hydrophilic interaction liquid chromatography (HILIC)-MS(/MS) as alternatives to the mouse bioassay method. However, post-column derivatization requires a system for online derivatization reactions, and with the ion-pair LC-MS approach, it is difficult to remove residual ion-pair reagents remaining in the equipment. Moreover, HILIC-MS provides poor separation compared to reversed-phase (RP) HPLC and requires a long time to reach equilibration. Therefore, we decided to develop a TTX analytical method using pre-column derivatization and RP HPLC for the rapid assessment of outbreak samples, including food remnants. In this study, we focused on the vic-diol moiety of TTX and designed a new derivatization reagent coded as NBD-H-DAB. This NBD-H-DAB was synthesized from 4-hydrazino-7-nitro-2,1,3-benzoxadiazole (NBD-H) and 3-fluoro-2-formylphenylboronic acid (FFPBA) with a simple reaction system and rapidly converted to its boronate form, coded NBD-H-PBA, in an aqueous reaction solution. The NBD-H-PBA demonstrated appropriate hydrophobicity to be retained on the RP analytical column and successfully detected with a UV spectrometer. It was easily reacted with the vic-diol moiety of TTX (C6 and C11) to synthesized a boronic ester. The derivatized TTX could be detected using the RP HPLC-UV, and the limit of detection in the fish flesh samples was 0.06 mg/kg. This novel pre-column derivatization of TTX with NBD-H-PBA proves capable for the analysis of TTX. [ABSTRACT FROM AUTHOR]

A molybdenum‐catalyzed approach for intermolecular C−N coupling that produces aryl‐ and heteroaryl amines has been developed under microwave irradiation. The formation of C−N bonds with boronic acids and nitroaromatics using readily available catalysts remains a challenge. The method we developed employs a combination of readily available sodium molybdate dihydrate as a catalyst and tri‐n‐butyl phosphine as an inexpensive reductant to achieve reductive intermolecular coupling of nitroarenes with boronic acids. This approach has shown its versatility in facilitating the formation of Csp2−N bonds from aryl‐boronic acids as well as Csp3−N bonds from alkyl‐boronic acids. In addition, this reaction shows stereospecificity when Csp3−N bonds are formed. An array of boronic acids underwent C−N coupling with nitro arene providing the desired products in good yields [ABSTRACT FROM AUTHOR]

Stable boroxine-amine adducts comprising dative B←N bond(s) were prepared by mechanochemically-induced reactions of phenylboronic acid (PBA) and amines (pyridine, DMAP, 1Hpyrazole, piperidine, DABCO, hexamethylenetetramine, or 4,4'-bipyridine). In-situ Raman monitoring, ex-situ PXRD and DFT calculations were used for product identification. Stoichiometry of the product (3: 1, 3:2 or 6:1 adduct) was controlled by the amine structure and the molar ratio of the reactants. The 1:2 Hbonded assembly of PBA and 4,4'-bipyridine (bpy) was confirmed as an intermediate in the adduct formation for bpy. Competitive binding experiments indicated that the exchange of the amines in the 3:1 adducts follows the computed adduct stabilities that increase with the amine basicity. Following the DFT prediction, the first adduct with two different amines, DMAP and pip, bound to one boroxine moiety was isolated and structurally characterized. Results show that calculations can be used to predict possible and preferred product(s) and their spectral characteristics. [ABSTRACT FROM AUTHOR]

A concise, convergent, and enantioselective synthesis of (−)‐6,7‐secoagroclavine, a pivotal intermediate in the synthesis of both clavine and ergot alkaloids, was accomplished from a derivative of the renowned Uhle's ketone. The synthesis is centered on metal‐free reductive coupling of the tosylhydrazone derivative of protected 4‐amino Uhle's ketone and commercially available 2,2‐dimethylethenylboronic acid, which is used as a four‐carbon building block. This novel approach directly sets the stereochemistry on the difficult‐to‐access aryl vinyl methane carbon stereogenic center of (−)‐6,7‐secoagroclavine. [ABSTRACT FROM AUTHOR]

The accurate thermosensing requires a minimum impact of autofluorescence and light scattering from the samples. In this study, we discovered that commercially available benzene‐1,4‐diboronic acid (BDBA) doped co‐crystals with trimethylolpropane (TMP) exhibit excellent thermochromic dual phosphorescence properties over a wide temperature range from −132 to 40 °C, despite its simple structure that does not have any donor‐acceptor linkage. The dual phosphorescence was consisted of monomeric benzene‐1,4‐diboronate (BDBA ester) and aggregation‐stabilized species. With an increase in temperature, the emission intensity from the monomeric state significantly decreased, whereas that originating from the aggregated state remained almost constant owing to the difference in their thermal stabilities. Further investigation revealed that molecular distortions in singlet excited states enable efficient intersystem crossing, causing efficient phosphorescence from the monomeric state of BDBA ester. [ABSTRACT FROM AUTHOR]

Incorporating nanoparticles into injectable hydrogels is a well-known technique for improving the mechanical properties of these materials. However, significant differences in the mechanical properties of the polymer matrix and the nanoparticles can result in localized stress concentrations at the polymer–nanoparticle interface. This situation can lead to problems such as particle–matrix debonding, void formation, and material failure. This work introduces boronic acid/boronate ester dynamic covalent bonds (DCBs) as energy dissipation sites to mitigate stress concentrations at the polymer–nanoparticle interface. Once boronic acid groups were immobilized on the surface of SiO2 nanoparticles (SiO2-BA) and incorporated into an alginate matrix, the nanocomposite hydrogels exhibited enhanced viscoelastic properties. Compared to unmodified SiO2 nanoparticles, introducing SiO2 nanoparticles with boronic acid on their surface improved the structural integrity and stability of the hydrogel. In addition, nanoparticle-reinforced hydrogels showed increased stiffness and deformation resistance compared to controls. These properties were dependent on nanoparticle concentration. Injectability tests showed shear-thinning behavior for the modified hydrogels with injection force within clinically acceptable ranges and superior recovery.

An overexpression of sialic acid is an indicator of metastatic cancer, and selective detection of sialic acid shows potential for cancer diagnosis. Boronic acid is a promising candidate for this purpose because of its ability to specifically bind to sialic acid under acidic conditions. Notably, the binding strength can be easily modulated by adjusting the pH, which allows for a simple dissociation of the bound sialic acid. In this study, we developed 5-boronopicolinic acid (5-BPA)-modified magnetic particles (BMPs) to selectively capture sialic acid biomolecules. We successfully captured fetuin, a well-known sialoglycoprotein, on BMPs at >104 molecules/particle using an acetate buffer (pH 5.0). Facile dissociation then occurred when the system was changed to a pH 7.6 phosphate buffer. This capture-and-release process could be repeated at least five times. Moreover, this system could enrich fetuin by more than 20 times. In summary, BMPs are functional particles for facile purification and concentration through the selective capture of sialic acid proteins and can improve detection sensitivity compared with conventional methods. This technology shows potential for the detection of sialic acid overexpression by biological particles. [ABSTRACT FROM AUTHOR]

Boronic acid‐containing molecules are substantially popularized in chemical biology and medicinal chemistry due to the broad spectrum of covalent conjugations as well as interaction modules offered by the versatile boron atom. Apparently, the WGA peptide (wheat germ agglutinin, 62–73), which shows a considerably low binding affinity to sialic acid, turned into a selective and >5 folds potent binder with the aid of a suitable boronic acid probe installed chemoselectively. In silico studies prompted us to install BA probes on the cysteine residue, supposedly located in close proximity to the bound sialic acid. In vitro studies revealed that the tailored boronopeptides show enhanced binding ability due to the synergistic recognition governed by selective non‐covalent interactions and cis‐diol boronic acid conjugation. The intense binding is observed even in 10 % serum, thus enabling profiling of sialyl‐glycan on cancer cells, as compared with the widely used lectin, Sambucus nigra. The synergistic binding mode between the best boronopeptide (P3) binder and sialic acid was analyzed via 1H and 11B NMR. [ABSTRACT FROM AUTHOR]

This article discusses the use of boronic acids in the synthesis of phenols, which are important compounds found in natural products and pharmaceuticals. The researchers focus on developing environmentally friendly and sustainable methods for preparing phenols from boronic acids. They explore different photocatalysts and solvents to optimize the oxidation reaction. The study finds that anthraquinone is an effective photocatalyst and 2-Me-THF is the best solvent for the reaction. The researchers aim to provide a more sustainable protocol for the oxidation of boronic acids. Another study described in the document investigates the photochemical aerobic oxidation of boronic acids to phenols. The researchers tested different additives and found that N,N'-diisopropylethylamine (DIPEA) was the most suitable base, resulting in the complete formation of phenol. They also explored the range of substrates and found that various aryl-substituted boronic acids could be converted into the corresponding phenols with moderate to excellent yields. Mechanistic studies suggested a mixed pathway involving the generation of a superoxide anion and the formation of hydrogen peroxide. Overall, this study presents an environmentally friendly and efficient method for the oxidation of boronic acids. [Extracted from the article]

The development of polysaccharide drugs requires a thorough understanding of their quantitative and pharmacokinetic properties. However, the complexity of biological samples presents a challenge for direct analysis using UHPLC-QTOF MS. Therefore, it is essential to establish a method for the selective enrichment of polysaccharides. In this study, we developed an efficient method for the quantitative determination of polysaccharides by integrating magnetic molecularly imprinted polymers (MIPs) for sample pretreatment and UHPLC-QTOF MS for analysis. The MIPs were prepared using molecularly imprinted and boric acid affinity technologies, which combined the advantages of specific recognition and reversible binding to polysaccharides. The MIPs exhibited high dispersibility and uniform particle size, and adsorption experiments demonstrated their specific recognition of BG136, a polysaccharide with immunological activity. The proposed method was used for the purification and enrichment of BG136 in plasma with recoveries between 91.29% and 113.03%. This simple method demonstrated high selectivity, fast separation, and satisfactory recoveries providing an approach for polysaccharide determination with UHPLC-QTOF MS. [ABSTRACT FROM AUTHOR]

Detection of sialic acid using advanced sensors in milk-based products is essential in the food industry. Therefore, the present work reports the sulfur and nitrogen-doped graphene quantum dots from bone meal functionalized with boronic acid (Boro-S/N-dGQDs) nanoprobe for sialic acid sensing applications. Briefly, S/N-dGQDs were functionalized with 4-carboxyphenylboronic acid to improve performance of fluorescent sensors toward the detection of sialic acid. Here, boronic acid surface decoration on S/N-dGQD was confirmed by several spectral characterizations. The addition of different quantities of sialic acid results in a directly proportionate correlation to fluorescence quenching. It gives a broad linear range of 50 ng/mL to 1000 ng/mL and a limit of detection of 6.04 ng/mL. Also, it displayed remarkable selectivity, likely due to interaction of sialic acid-containing 1,2-diol with hydroxyl group of Boro-S/N-dGQDs nanoprobe. Designed sensor demonstrated good stability and reproducibility. Real-time analysis of sialic acid in different milk-based products confirmed practicability of Boro-S/N-dGQDs. [ABSTRACT FROM AUTHOR]

The complexation of boric acid (BA) with various α-hydroxycarboxylic acids (HCAs) was examined by analyzing the change in the optical rotation after the addition of BA to aqueous HCA solutions, and the catalytic properties of the complexes were examined by catalyzing the esterification of the HCAs. The absolute values of the optical rotation of the HCAs increased with increasing BA-to-HCA molar ratio, and the rate of change of the optical rotation gradually decreased as the BA-to-HCA molar ratio increased, reaching a minimum value at a molar ratio of approximately three. As a catalyst, BA could catalyze the acetylation of hydroxyl groups in addition to the esterification of HCAs. Compared to the conventional synthesis routes of ATBC and ATOC, a synthesis route with BA as the catalyst allowed for a lower frequency of catalyst separation and replacement while providing light-colored products. BA could catalyze the formation of triethyl citrate, and the yield of triethyl citrate reached 93.8%. BA could also catalyze the reaction between malic acid and pinene to produce borneol malate. After saponification of borneol malate, borneol was obtained with a yield of 39%. [ABSTRACT FROM AUTHOR]

The activation of molecular hydrogen is a key process in catalysis. Here, we demonstrate how polyoxometalate (POM)‐based heterogeneous compounds functionalized with Platinum particles activate H2 by synergism between a hydrogen spillover mechanism and electron‐proton transfer by the POM. This interplay facilitates the selective catalytic reduction of olefins and nitroarenes with high functional group tolerance. A family of polyoxotungstates covalently functionalized with boronic acids is reported. In the solid‐state, the compounds are held together by non‐covalent interactions (π–π stacking and hydrogen bonding). The resulting heterogeneous nanoscale particles form stable colloidal dispersions in acetonitrile and can be surface‐functionalized with platinum nanoparticles by in situ photoreduction. The resulting materials show excellent catalytic activity in hydrogenation of olefins and nitrobenzene derivatives under mild conditions (1 bar H2 and room temperature). [ABSTRACT FROM AUTHOR]

Boronic acids/esters have recently emerged in the field of medicinal and pharmaceutical research due to their exceptional oxophilicity, low toxicity, and unique structure. They are known as potent enzyme inhibitors, cancer therapy capture agents, and can mimic certain types of antibodies to fight infections. They have been designed and developed into drugs, and this approach has emerged in the last 20 years. Five boronic acid drugs have been approved by the FDA and Health Canada, two of which are used to treat cancer, specifically multiple myeloma. The purpose of this review is to investigate boronic acid/ester derivatives as potential pharmaceutical agents as well as the mechanism of action. It will concentrate on six types of cancer: multiple myeloma, prostate cancer, breast cancer, lung cancer, cervical cancer, and colon cancer. Some newly developed boron-containing compounds have already demonstrated highly promising activities, but further investigation is required before final conclusions can be drawn. [ABSTRACT FROM AUTHOR]

This study outlines the development of novel boronic acids as catalysts for the direct synthesis of amides from carboxylic acids and amines. The Lewis acidity of the boronic acids was estimated by means of computational techniques, and the observed increase in catalytic activity was corroborated by kinetic data derived from a model reaction. Our investigations led to the discovery of a set of ortho‐(sulfonyloxy)benzeneboronic acids that compared favorably with the established state‐of‐the‐art. These newly developed catalysts demonstrated efficacy in the coupling of aliphatic, aromatic, and heteroaromatic acids, as well as primary and secondary amines. [ABSTRACT FROM AUTHOR]

This study focuses on the development of antimicrobial fibres for use in medical and healthcare textile industries. Carbon dots (CDs) were designed with boronic acid groups for the attachment to cellulose fibres found in cotton textiles and to enhance their attachment to glycogens on bacterial surfaces. Boronic acid-based and curcumin-based CDs were prepared and characterized using various techniques, showing a nanoscale size and zeta potential values. The CDs inhibited the growth of both Staphylococcus epidermidis and Escherichia coli bacteria, with UV-activated CDs demonstrating improved antibacterial activity. The antimicrobial activity of the CDs was then tested, revealing strong adherence to cellulose paper fibres with no CD diffusion and potent inhibition of bacterial growth. Cytotoxicity assays on human cell lines showed no toxicity towards cells at concentrations of up to 100 µg ml−1 but exhibited increased toxicity at concentrations exceeding 1000 µg ml−1. However, CD-modified cellulose paper fibres showed no toxicity against human cell lines, highlighting the antimicrobial properties of the CD-modified cellulose fibres are safe for human use. These findings show promising potential for applications in both industrial and clinical settings.

Herein, we investigated hydrogels composed of boronic-acid-functionalized alginate and blended with polyvinyl alcohol (PVA) of different molecular weights to control the release of metoclopramide hydrochloride as a function of pH and shear stress. The functionalization of alginate introduced dynamic covalent bonding and pH-responsive properties that can modulate network connectivity. The study investigated the viscoelastic properties of the hydrogels, their drug release profiles, and their responsiveness to changes in pH and shear forces. The results showed that a higher PVA molecular weight and alkaline pH conditions increased hydrogel viscosity and stiffness due to a more stable and interconnected network structure than acidic pH. Metoclopramide release revealed that the hydrogels exhibited pH-responsive drug release behavior. The drug was more readily released under acidic conditions due to the instability of sp2-hybridized boronate ester bonds. The influence of shear forces on the release of metoclopramide was also investigated at shear rates of 1, 10, and 100 s−1, revealing their effect on matrix stiffening. Research shows that AlgBA/PVA hydrogels have unique properties, such as dynamic covalent bonding, that make them sensitive to external mechanical forces. This sensitivity makes them ideal for applications where physiological conditions trigger drug release.

Tetrodotoxin (TTX) is a representative natural toxin causing pufferfish food poisoning, which is especially prominent in East and Southeast Asia, including Japan. TTX has been analyzed through post-column derivatization high-performance liquid chromatography (HPLC), ion-pair LC-MS(/MS), and hydrophilic interaction liquid chromatography (HILIC)-MS(/MS) as alternatives to the mouse bioassay method. However, post-column derivatization requires a system for online derivatization reactions, and with the ion-pair LC-MS approach, it is difficult to remove residual ion-pair reagents remaining in the equipment. Moreover, HILIC-MS provides poor separation compared to reversed-phase (RP) HPLC and requires a long time to reach equilibration. Therefore, we decided to develop a TTX analytical method using pre-column derivatization and RP HPLC for the rapid assessment of outbreak samples, including food remnants. In this study, we focused on the vic-diol moiety of TTX and designed a new derivatization reagent coded as NBD-H-DAB. This NBD-H-DAB was synthesized from 4-hydrazino-7-nitro-2,1,3-benzoxadiazole (NBD-H) and 3-fluoro-2-formylphenylboronic acid (FFPBA) with a simple reaction system and rapidly converted to its boronate form, coded NBD-H-PBA, in an aqueous reaction solution. The NBD-H-PBA demonstrated appropriate hydrophobicity to be retained on the RP analytical column and successfully detected with a UV spectrometer. It was easily reacted with the vic-diol moiety of TTX (C6 and C11) to synthesized a boronic ester. The derivatized TTX could be detected using the RP HPLC-UV, and the limit of detection in the fish flesh samples was 0.06 mg/kg. This novel pre-column derivatization of TTX with NBD-H-PBA proves capable for the analysis of TTX.

The wide use of boronic compounds, especially boronic acids and benzoxaboroles, in virtually all fields of chemistry is related to their specific properties. The most important of them are the ability to form cyclic esters with diols and the complexation of anions. In both cases, the equilibrium of the reaction depends mainly on the acidity of the compounds, although other factors must also be taken into account. Quantification of the acidity (pKa value) is a fundamental factor considered when designing new compounds of practical importance. The aim of the current work was to collect available values of the acidity constants of monosubstituted phenylboronic acids, critically evaluate these data, and supplement the database with data for missing compounds. Measurements were made using various methods, as a result of which a fast and reliable method for determining the pKa of boronic compounds was selected. For an extensive database of monosubstituted phenylboronic acids, their correlation with their Brønsted analogues—namely carboxylic acids—was examined. Compounds with ortho substituents do not show any correlation, which is due to the different natures of both types of acids. Nonetheless, both meta- and para-substituted compounds show excellent correlation. From a practical point of view, acidity constants are best determined from the Hammett equation. Computational approaches for determining acidity constants were also analyzed. In general, the reported calculated values are not compatible with experimental ones, providing comparable results only for selected groups of compounds.

Boronic acids/esters have recently emerged in the field of medicinal and pharmaceutical research due to their exceptional oxophilicity, low toxicity, and unique structure. They are known as potent enzyme inhibitors, cancer therapy capture agents, and can mimic certain types of antibodies to fight infections. They have been designed and developed into drugs, and this approach has emerged in the last 20 years. Five boronic acid drugs have been approved by the FDA and Health Canada, two of which are used to treat cancer, specifically multiple myeloma. The purpose of this review is to investigate boronic acid/ester derivatives as potential pharmaceutical agents as well as the mechanism of action. It will concentrate on six types of cancer: multiple myeloma, prostate cancer, breast cancer, lung cancer, cervical cancer, and colon cancer. Some newly developed boron-containing compounds have already demonstrated highly promising activities, but further investigation is required before final conclusions can be drawn.

Herein we report a protocol for the generation of alkyl carbon radicals from alkylboronic acids wherein photoexcited 4‐nitropyridine N‐oxide biradical features a catalyst to promote the nucleo‐homolytic substitution of boronic acids. With a wide range of readily available aliphatic boronic acids, including methyl boronic acid, the developed catalytic system demonstrates broad applicability for alkylation, amination, and cyanation. [ABSTRACT FROM AUTHOR]

Stimuli‐responsive hydrogels have attracted much attention owing to the versatility of their programmed response in offering intelligent solutions for biomimicry applications, such as soft robotics, tissue engineering, and drug delivery. To achieve the complexity of biomimetic structures, two photon polymerization (2PP) has provided a means of fabricating intricate 3D structures from stimuli‐responsive hydrogels. Rapid swelling hydrogel microstructures are advantageous for osmotically driven stimuli‐response, where actuation speed, that is reliant on the diffusion of analytes or bioanalytes, can be optimized. Herein, the flexibility of 2PP is exploited to showcase a novel sugar‐responsive, phenylboronic acid‐based photoresist. This offers a remarkable solution for achieving fast response hydrogel systems that have been often hindered by the volume‐dependent diffusion times of analytes to receptor sites. A phenylboronic acid‐based photoresist compatible with 2PP is presented to fabricate stimuli‐responsive microstructures with accelerated response times. Moreover, microstructures with programmable actuation (i.e., bending and opening) are fabricated using the same photoresist within a one‐step fabrication process. By combining the flexibility of 2PP with an easily adaptable photoresist, an accessible fabrication method is showcased for sophisticated and chemo‐responsive 3D hydrogel actuators. [ABSTRACT FROM AUTHOR]

We have developed a straightforward methodology for converting arylboronic acids into phenols using NaOH‐mediated air oxidation. This reaction offers several advantages, including simple operation, excellent tolerance towards various functional groups, and scalability. The transmetalation of the resulting borate ester with NaOH occurs readily, enabling convenient derivatization of the borate ester into aryl ethers and esters using alkyl and acyl halides. [ABSTRACT FROM AUTHOR]

Bacteria are becoming more and more resistant to β-lactam antibiotics. One approach to lower such resistance involves combining inhibitors of β-lactamase with β-lactams antibiotics. As such, the need for innovative inhibitors of β-lactamases is urgent. Therefore, the aim of this research was to design and dock two new series of amides and Schiff bases of the cyclic and noncyclic boronate derivatives into four subtypes from two different classes of the β-lactamase enzymes. In silico prediction of the pharmacokinetic profile of the designed compounds was also performed. The results revealed possible enhanced activity of 15 out of the 82 compounds, when matched with 4 existing β-lactamase inhibitors (clavulanic acid, sulbactam, tazobactam and vaborbactam). The 15 compounds showed favorable docking interactions with the residues in the active site of all enzymes. The predicted pharmacokinetic characteristics also showed that the 15 compounds are promising as oral agents. The designed compounds have the potential to act as inhibitors of β-lactamase as shown by their docking results on 4 β-lactamase crystal structures. The pharmacokinetic profile of 15 compounds is also promising, making them suitable candidates for synthesis and in vitro testing. [ABSTRACT FROM AUTHOR]

Ellagic acid (EA) is a natural polyphenol and possesses excellent in vivo bioactivity and antioxidant behaviors, which play an important role in the treatment of oxidative stress-related diseases, such as cancer. Additionally, EA is also known as a skin-whitening ingredient. The content of EA would determine its efficacy. Therefore, the accurate analysis of EA content can provide more information for the scientific consumption of EA-rich foods and cosmetics. Nevertheless, the analysis of EA in these samples is challenging due to the low concentration level and the presence of interfering components with high abundance. Molecularly imprinted polymers are highly efficient pretreatment materials in achieving specific recognition of target molecules. However, the traditional template molecule (EA) could not be absolutely removed. Hence, template leakage continues to occur during the sample preparation process, leading to a lack of accuracy in the quantification of EA in actual samples, particularly for trace analytes. In addition, another drawback of EA as an imprinting template is that EA possesses poor solubility and a high price. Gallic acid (GA), called dummy templates, was employed for the synthesis of MIPs as a solution to these challenges. The approach used in this study was boronate affinity-based oriented surface imprinting. The prepared dummy-imprinted nanoparticles exhibited several significant advantages, such as good specificity, high binding affinity ((4.89 ± 0.46) × 10−5 M), high binding capacity (6.56 ± 0.35 mg/g), fast kinetics (6 min), and low binding pH (pH 5.0) toward EA. The reproducibility of the dummy-imprinted nanoparticles was satisfactory. The dummy-imprinted nanoparticles could still be reused even after six adsorption–desorption cycles. In addition, the recoveries of the proposed method for EA at three spiked levels of analysis in strawberry and pineapple were 91.0–106.8% and 93.8–104.0%, respectively, which indicated the successful application to real samples.

The quinolone–quinoline tautomerization is harnessed to effect the regioselective C8‐borylation of biologically important 4‐quinolones by using [Ir(OMe)(cod)]2 as the catalyst precursor, the silica‐supported monodentate phosphine Si‐SMAP as the ligand, and B2pin2 as the boron source. Initially, O‐borylation of the quinoline tautomer takes place. Critically, the newly formed 4‐(pinBO)‐quinolines then undergo N‐directed selective Ir‐catalyzed borylation at C8. Hydrolysis of the OBpin moiety on workup returns the system to the quinolone tautomer. The C8‐borylated quinolines were converted to their corresponding potassium trifluoroborate (BF3K) salts and to their C8‐chlorinated quinolone derivatives. The two‐step C‐H borylation‐chlorination reaction sequence resulted in various C8‐Cl quinolones in good yields. Conversion to C8‐OH‐, C8‐NH2‐, and C8‐Ar‐substituted quinolones was also feasible by using this methodology. [ABSTRACT FROM AUTHOR]

We have developed an improved method for generating aryne from o‐triazenylarylboronic acids. Unlike the previous method that required excess o‐triazenylarylboronic acids as aryne precursors, we used corresponding boronates as limiting reagents, which resulted in high yields. By combining the formation of boronates and aryne generation through silica gel treatment in one‐pot, we were able to effectively use a wide range of o‐triazenylarylboronic acids in reactions with various arynophiles. This one‐pot method was particularly suitable for transforming complex aryne precursors with different functional groups. [ABSTRACT FROM AUTHOR]

It is of great importance to have sensitive and accurate detection of cis-diol-containing biologically related substances because of their important functions in the research fields of metabolomics, glycomics, and proteomics. Boronic acids can specifically and reversibly interact with 1,2- or 1,3-diols to form five or six cyclic esters. Based on this unique property, boronic acid-based materials have been used as synthetic receptors for the specific recognition and detection of cis-diol-containing species. This review critically summarizes the recent advances with boronic acid-based materials as recognition elements and signal labels for the detection of cis-diol-containing biological species, including ribonucleic acids, glycans, glycoproteins, bacteria, exosomes, and tumor cells. We also address the challenges and future perspectives for developing versatile boronic acid-based materials with various promising applications. [ABSTRACT FROM AUTHOR]

Finding an ideal bioorthogonal reaction that responds to a wide range of biological queries and applications is of great interest in biomedical applications. Rapid diazaborine (DAB) formation in water by the reactions of ortho‐carbonyl phenylboronic acid with α‐nucleophiles is an attractive conjugation module. Nevertheless, these conjugation reactions demand to satisfy stringent criteria for bioorthogonal applications. Here we show that widely used sulfonyl hydrazide (SHz) offers a stable DAB conjugate by combining with ortho‐carbonyl phenylboronic acid at physiological pH, competent for an optimal biorthogonal reaction. Remarkably, the reaction conversion is quantitative and rapid (k2>103 M−1 s−1) at low micromolar concentrations, and it preserves comparable efficacy in a complex biological milieu. DFT calculations support that SHz facilitates DAB formation via the most stable hydrazone intermediate and the lowest energy transition state compared to other biocompatible α‐nucleophiles. This conjugation is extremely efficient on living cell surfaces, enabling compelling pretargeted imaging and peptide delivery. We anticipate this work will permit addressing a wide range of cell biology queries and drug discovery platforms exploiting commercially available sulfonyl hydrazide fluorophores and derivatives. [ABSTRACT FROM AUTHOR]

The new Lewis acid–base adducts of general formula X(nad)B←NC5H4-C5H4N→B(nad)X [nad = 1,8-O2C10H6, X = C6H5 (2c), 3,4,5-F3-C6H2 (2d)] were synthesized in high yields via reactions of 1,8-dihydroxy naphthalene [nadH2] and 4,4′-bipyridine with the aryl boronic acids C6H5B(OH)2 and 3,4,5-F3-C6H2B(OH)2, respectively, and structurally characterized by multi-nuclear NMR spectroscopy and SCXRD. Self-assembled H-shaped Lewis acid–base adduct 2d proved to be effective in forming thermally stable host–guest complexes, 2d × solvent, with aromatic hydrocarbon solvents such as benzene, toluene, mesitylene, aniline, and m-, p-, and o-xylene. Crystallographic analysis of these solvent adducts revealed host–guest interactions to primarily occur via π···π contacts between the 4,4′-bipyridyl linker and the aromatic solvents, resulting in the formation of 1:1 and 1:2 host–guest complexes. Thermogravimetric analysis of the isolated complexes 2d × solvent revealed their high thermal stability with peak temperatures associated with the loss of solvent ranging from 122 to 147 °C. 2d, when self-assembled in an equimolar mixture of m-, p-, and o-xylene (1:1:1), preferentially binds to o-xylene. Collectively, these results demonstrate the ability of 1,8-dihydroxy naphthalene to serve as an effective building block in the selective self-assembly to supramolecular aggregates through dative covalent N→B bonds. [ABSTRACT FROM AUTHOR]

This work reports the development of a fluorescence method for the detection of poly(ADP-ribose) polymerase-1 (PARP1), in which a phenylboronic acid-modified fluorescein isothiocyanate dye (FITC-PBA) was used to recognize the formed poly(ADP-ribose) (PAR) polymer. The detection system was designed by conjugating recombinant streptavidin (rSA) with PARP1-specific double-stranded DNA (dsDNA) through streptavidin–biotin interaction. Capture of PARP1 via rSA–biotin–dsDNA allowed for the poly-ADP-ribosylation (PARylation) of both rSA and PARP1 in a homogeneous solution. The resulting rSA–biotin–dsDNA/PAR conjugates were then captured and separated via the commercialized nitrilotriacetic acid–nickel ion-modified magnetic bead (MB-NTA-Ni) through the interaction between NTA–Ni on MB surface and oligohistidine (His6) tag in rSA. The PAR polymer could capture the dye of FITC-PBA through the borate ester interaction between the boronic acid moiety in PBA and the cis-diol group in ribose, thus causing a decrease in fluorescence signal. The PARylation of streptavidin and the influence of steric hindrance on PARylation efficiency were confirmed using reasonable detection strategies. The method showed a wide linear range (0.01~20 U) and a low detection limit (0.01 U). This work should be valuable for the development of novel biosensors for the detection of poly(ADP-ribose) polymerases and diol-containing species. [ABSTRACT FROM AUTHOR]

Drug leads with a high Fsp3 index are more likely to possess desirable properties for progression in the drug development pipeline. This paper describes the development of an efficient two-step protocol to completely diastereoselectively access a diethanolamine (DEA) boronate ester derivative of monosaccharide d-galactose from the starting material 1,2:5,6-di-O-isopropylidene-α-d-glucofuranose. This intermediate, in turn, is used to access 3-boronic-3deoxy-d-galactose for boron neutron capture therapy (BNCT) applications. The hydroboration/borane trapping protocol was robustly optimized with BH3.THF in 1,4-dioxane, followed by in-situ conversion of the inorganic borane intermediate to the organic boron product by the addition of DEA. This second step occurs instantaneously, with the immediate formation of a white precipitate. This protocol allows expedited and greener access to a new class of BNCT agents with an Fsp3 index = 1 and a desirable toxicity profile. Furthermore, presented is the first detailed NMR analysis of the borylated free monosaccharide target compound during the processes of mutarotation and borarotation. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is one of the important reactive oxygen species (ROS), which is closely related to many pathological and physiological processes in living organisms. Excessive H2O2 can lead to cancer, diabetes, cardiovascular diseases, and other diseases, so it is necessary to detect H2O2 in living cells. Since this work designed a novel fluorescent probe to detect the concentration of H2O2, the H2O2 reaction group arylboric acid was attached to the fluorescein 3-Acetyl-7-hydroxycoumarin as a specific recognition group for the selective detection of hydrogen peroxide. The experimental results show that the probe can effectively detect H2O2 with high selectivity and measure cellular ROS levels. Therefore, this novel fluorescent probe provides a potential monitoring tool for a variety of diseases caused by H2O2 excess. [ABSTRACT FROM AUTHOR]