4-vinylphenylboronic Acid Research Articles

Rapid analysis of six cytokinins in tomato plants using phenylboronic acid and ionic liquid functionalized monolithic capillary column combined with UHPLC-MS/MS

In this study, 4-vinylphenylboronic acid, ionic liquid, and dipentaerythritolhexakis(3-mercaptopropionate) were used as functional monomers to prepare monolithic column in fused-silica capillaries by thermally induced sulfhydryl-alkenyl click polymerization. Based on the properties of 4-vinylphenylboronic acid and ionic liquid, the monolithic capillary column (VPBA-SH-IL) exhibited excellent permeability and chemical stability with the ability to efficiently enrich trace amounts of cytokinins from complex substrates via B←N coordination, π-π interactions, cation-π interactions, S-π interactions and hydrophobic interactions. Under the optimal adsorption conditions, the adsorption efficiency of VPBA-SH-IL for six cytokinins could reach more than 95 %, and the adsorption capacities ranged from 0.18 to 0.99 mg·m−1. A reliable and sensitive method for the determination of six cytokinins in organs of tomato (root, stem, leaf and fruit) was established by using the monolithic capillary column as in-tube solid-phase microextraction coupled with UHPLC-MS/MS. The developed method showed a wide linear range (0.010–10.0 μg·L−1) and low limits of detection (1.6–3.3 ng·L−1). The recoveries of the six cytokinins in spiked samples ranged from 80.6 % to 108 % with the relative standard deviations of 2.4–8.7 % (n = 5). The VPBA-SH-IL shows good potential for extraction and analysis of trace cytokinins in complex matrices such as plants, which is of great significance in exploring the mechanism of plant growth and development.

Facile synthesis of active sites-rich magnetic adsorbent by simple one-pot hydrothermal strategy for quick and highly capable capture of female-steroid hormones

Rapid and efficient extraction is highly desired in the accurate quantification of female-steroid hormones (FSHs) in complex samples. In this context, an active sites-rich magnetic adsorbent (MAC) modified with carboxylated multiwalled carbon nanotubes and 4-vinylphenylboronic acid was facilely synthesized through one-pot hydrothermal technique for the magnetic solid phase extraction (MSPE) of FSHs in water and urine samples. Various characterizations revealed that the prepared adsorbent contained abundant functional groups, acceptable magnetic properties, high surface area and good stability. Due to the multiple interactions, the developed MAC/MSPE exhibited high isolation and preconcentration capability towards studied FSHs within 10 min. The concentration factors were 151–354 and the adsorption capacity was as high as 3.2 mg/g. Adsorption behaviors of MAC/MSPE towards FSHs were studied based on adsorption kinetics and isotherm experiments. After optimizing the extraction parameters, the MAC/MSPE was combined with HPLC to sensitive and reliable monitoring of studied FSHs in various waters and female urine samples. The limits of detection and recoveries with different spiked contents were 0.0015–0.0026 μg/L and 80.1–119 %, respectively. Accuracy of the established method was evaluated by confirmatory testing. Moreover, sample preparation greenness of the developed method was assessed. The present study uncovered the prospect of MAC/MSPE in the rapid and highly capable capture of FSHs, and also supplied a sensitive and reliable approach for the monitoring of trace FSHs in complex samples.

Injectable Gelled Multiple Emulsion for Glucose-Responsive Insulin Delivery.

A glucose-responsive insulin delivery system that sustains blood glucose equilibrium for an extended duration can address the low therapeutic window of insulin in diabetes treatment. Herein, insulin is loaded in a water-in-oil-in-water (W1/O/W2) gelled multiple emulsion using poly (4-vinylphenylboronic acid) (PVPBA) homopolymer as an effective emulsifier. The gelled multiple emulsion exhibits a high encapsulation efficiency (99%), enhanced stability and remarkable shear-thinning behavior, making it easy to inject. Under hyperglycemic conditions, the gelled emulsion system instantly binds to glucose molecules and reduces the hydrogen bonds of the PVPBA homopolymer, resulting in insulin release. In a streptozotocin-induced type 1 diabetic mouse model, a single subcutaneous injection of the gelled emulsion rapidly responds to high blood glucose concentration (BGC)and release insulin in a glucose dependent manner, thus prolonging the antihyperglycemic effect compared with free insulin.

Novel water-compatible surface molecularly imprinted polymer microspheres based on boronate affinity and hydrophilic coating for efficient enrichment and separation of capecitabine from urine samples

A novel water-compatible surface molecularly imprinted polymer microspheres (SMIMs) based on boronate affinity and hydrophilic coating were developed for the specific recognition and extraction of capecitabine (CAP). The boronic acid-functionalized polymer microspheres (BPMs) were first prepared as the carrier through dispersion polymerization using methyl methacrylate, ethylene glycol dimethacrylate, and 4-vinylphenylboronic acid as the polymerization monomers. Subsequently, the CAP template was immobilized onto the surface of the BPMs by virtue of boronate affinity. Finally, a thin and adherent imprinting layer was coated onto the surface of the BPMs via in-water self-polymerization of dopamine (DA) and polyethyleneimine (PEI). The resulting SMIMs exhibited strong hydrophilicity, high adsorption capacity (151.52 μmol/g) and a great imprinting factor (5.99) for CAP in aqueous media. The adsorption behavior of CAP onto the SMIMs was in good agreement with the Langmuir model and the pseudo-second-order equation. Selective adsorption indicated that the SMIMs exhibited a higher specific recognition for CAP compared to other structural analogs. In addition, the SMIMs showed excellent reproducibility and reusability, and could be utilized as anadsorbent in solid-phase extraction (SPE) for the selective pre-concentration, purification, and detection of trace amounts of CAP in spiked urine samples in combination with HPLC. The elution recovery of CAP for the various spiked levels ranged from 91.7 % to 104.9 %, with a relative standard deviation (RSD) of less than 5.8 % (n = 3).

Highly Stretchable and Adhesive Soft Vitrimers Based on N →B Coordination Structure

Recently, vitrimers with a reversible N[Formula: see text]B coordination dynamic structure have garnered interest not only for their self-healing and reprocessable properties but also for their hydrolytic stability. Reported vitrimers with N[Formula: see text]B internal coordination dynamic structure were excessively rigid, limiting their stretchability and toughness. This study synthesized a cross-linking agent (DNCB) with a cyclic nitrogen-boron coordination structure. This agent was then used in copolymerization with n-butyl acrylate (BA) and 4-vinylphenylboronic acid (BOH) to create soft vitrimers. By systematically tuning the composition, soft vitrimers exhibit water resistance along with high viscoelasticity, stretchability, toughness, and adhesive properties against various substrates. The observed mechanical behavior is attributed to the rapid relaxation of N[Formula: see text]B coordination bonds and slow relaxation of B-O bonds in boroxine within the polymer network. It is anticipated that these soft vitrimers will be applied in adhesives, flexible electronics, and soft robotics due to their favorable properties.

Electrofluorochromic Switching of Heat-Induced Cross-Linkable Multi-Styryl-Terminated Triphenylamine and Tetraphenylethylene Derivatives.

High-performance electrochromic (EC) and electrofluorochromic (EFC) materials have garnered considerable interest due to their diverse applications in smart windows, optoelectronics, optical displays, military camouflage, etc. While many different EC and EFC polymers have been reported, their preparation often requires multiple steps, and their polymer molecular weights are subjected to batch variation. In this work, we prepared two triphenylamine (TPA)-based and two tetraphenylethylene (TPE)-based derivatives functionalized with terminal styryl groups via direct Suzuki coupling with (4-vinylphenyl)boronic acid and vinylboronic acid pinacol ester. The two novel TPE derivatives exhibited green-yellow aggregation-induced emission (AIE). The EC and EFC properties of pre- and post-thermally treated derivatives spin-coated onto ITO-glass substrates were studied. While all four derivatives showed modest absorption changes with applied voltages up to +2.4 V, retaining a high degree of optical transparency, they exhibited obvious EFC properties with the quenching of blue to yellow fluorescence with IOFF/ON contrast ratios of up to 7.0. The findings therefore demonstrate an elegant approach to preparing optically transparent, heat-induced, cross-linkable styryl-functionalized EFC systems.

Design of Stretchable and Conductive Self-Adhesive Hydrogels as Flexible Sensors by Guar-Gum-Enabled Dynamic Interactions.

The limited elasticity and inadequate bonding of hydrogels made from guar gum (GG) significantly hinder their widespread implementation in personalized wearable flexible electronics. In this study, we devise GG-based self-adhesive hydrogels by creating an interpenetrating network of GG cross-linked with acrylic, 4-vinylphenylboronic acid, and Ca2+. With the leverage of the dynamic interactions (hydrogen bonds, borate ester bonds, and coordination bonds) between -OH in GG and monomers, the hydrogel exhibits a high stretchability of 700%, superior mechanical stress of 110 kPa, and robust adherence to several substrates. The adhesion strength of 54 kPa on porcine skin is obtained. Furthermore, the self-adhesive hydrogel possesses stable conductivity, an elevated gauge factor (GF), and commendable durability. It can be affixed to the human body as a strain sensor to obtain precise monitoring of human movement behavior. Our research offers possibilities for the development of GG-based hydrogels and applications in wearable electronics and medical monitoring.

Super-Flexible Water-Proof Actuators.

Humidity-responsive materials hold broad application prospects in sensing, energy production, and other fields. Particularly, humidity-sensitive, flexibility, and water resistance are pivotal factors in the development of optimized humidity-responsive materials. In this study, hydrophobic linear polyurethane and hydrophilic 4-vinylphenylboronic acid (4-VPBA) form a semi-intercross cross-linking network. This copolymer of polyurethane exhibits excellent humidity-sensitive, mechanical properties, and water resistance. Its maximum tensile strength and maximum elongation can reach 40.56MPa and 543.47%, respectively. After being immersed in water at various temperatures for 15 days, it exhibited a swelling ratio of only 3.28% in water at 5°C and 9.58% in water at 70°C. While the presence of 4-VPBA network imparts humidity-sensitive, reversible, and multidirectional bending abilities, under the stimulus of water vapor, it can bend 43° within 1.4s. The demonstrated material surpasses current bidirectional humidity actuators in actuating ability. Based on these characteristics, automatically opening waterproof umbrellas and windows, as well as bionic-arms, crawling robots, and self-propelled boats, are successfully developed.

Highly efficient production and simultaneous purification of d-tagatose through one-pot extraction-assisted isomerization of d-galactose

A one-pot extraction-assisted d-galactose-to-d-tagatose isomerization strategy was proposed based on the selective extraction of d-tagatose by phenylborate anions. 4-Vinylphenylboronic acid was selected with high extraction efficiency and selectivity towards d-tagatose. The extracted sugars could be desorbed through a two-staged stripping process with the purity of d-tagatose significantly increased. In-situ extraction-assisted d-galactose-to-d-tagatose isomerization was implemented for the first time ever reported, and the effect of boron-to-sugar ratio (boron: sugar) was investigated. The conversion yield of d-tagatose at 60 °C increased from ∼ 39 % (boron: sugar = 0.5) to ∼ 56 % (boron: sugar = 1) but then decreased to ∼ 44 % (boron: sugar = 1.5). With temperature increased to 70 °C, the conversion yield of d-tagatose was further improved to ∼ 61 % (boron: sugar = 1.5), with the minimized formation of byproducts. Moreover, high purity (∼83 %) and concentrated d-tagatose solution (∼40 g/L) was obtained after sequential desorption. The proposed extraction-assisted isomerization strategy achieved improving the yield and purity of d-tagatose, proving its feasibility in industrial applications.

Multi-stimuli responsive boronic acid-containing polymers via recyclable nanoscale zerovalent iron (nZVI)-mediated photoRDRP in ionic liquid

A facile method based on recyclable nanoscale zero-valent iron (nZVI)-mediated photoRDRP in ionic liquid led to synthesis of narrow disperse poly(2-(dimethylamino)ethyl methacrylate) and poly(2-(dimethylamino)ethyl methacrylate)-block-poly(4-vinylphenylboronic acid) (PDMAEMA-b-PVPBA) diblock copolymers thereof. Stimuli response of the PDMAEMA-b-PVPBA copolymer against changes in pH, temperature and sugar concentration is assessed. Recyclability of the nZVI (catalyst) and ionic liquid (solvent) is established. Polymerization can be shut down or turned on simply by turning off or on the UV-A irradiation. This temporal control of the polymerization might be useful for wide use of the developed protocol for spatiotemporal “ON/OFF” control. DFT calculations are performed to get the geometry of the involved species.

Selective separation of target glycoproteins using boronate affinity imprinted copolymers: Precise identification and increase the number of recognition sites

The recognizing sites numbers and selectivity limitation of the sorbents itself is the main reason for the difficulty in increasing the target glycoproteins adsorption amount in the separation system.In this work, a new kind of porous block imprinted copolymers (BA-MF-CD-BA) with abundant boronic acid recognizing sites were firstly fabricated facilely synthesized through a in situ cross-linking copolymerization and host–guest interaction for specific separation of ovalbumin (OVA). The single boronate affinity recognizing sites are relatively difficult for selective capture glycoproteins of low concentration. This is because of that the single imprinted recognizing sites are generally related to the low adsorption performance and weak affinity. For solve these limitations, the high-density boronic acid recognizing sites were considered to grafted on the surface of sorbents. Firstly, the functional monomer 4-vinylphenylboronic acid (4-VBA) were used to prepare the matrix of boronate affinity copolymers with β-cyclodextrins (CDs). Subsequently, the CDs as a a linker to graft boronate affinity imprinted recognizing sites based adamantane (Ad) inclusion derivative, which can effectively increase the numbers of boronic acid recognizing sites. Owing to the abundant boronic acid recognizing sites synergistic binding, the as-prepared BA-MF-CD-BA exhibited high adsorption capacity towards OVA, which are approximately 3.5 orders higher than the affinity of single boronate affinity sorbents. Combining these excellent properties, BA-MF-CD-BA exhibit fast adsorption kinetics (30 min) and large adsorption capacities (129.12 mg g−1, pH = 8.0) at 298 K, and the existence of an evenly chemisorption monolayer is confirmed. Moreover, the high recyclability (after 8 cycles, 6.24% loss) demonstrated the BA-MF-CD-BAs’ practical application potential. In addition, BA-MF-CD-BA exhibited excellent selective adsorption performance of OVA from complex practical samples. This is because of that the high-density boronate affinity imprinted recognizing sites and the nanoporous structure of the imprinted copolymers matrix. Consequently, the high density boronate affinity imprinted copolymer can be an attractive option for selective enriching glycoproteins from practical samples.

Quantitation of tryptophan and kynurenine in human plasma using 4-vinylphenylboronic acid column by capillary electrochromatography coupled with mass spectrometry.

Tryptophan (TRP) is an essential amino acid catabolized mainly through the kynurenine pathway, and part of it is catabolized in the brain. The abnormal depletion of TRP and production of kynurenine (KYN) by two enzymes, tryptophan 2,3-dioxygenase (TDO) and indoleamine 2,3-dioxygenase (IDO), have been linked to various neurological diseases. The ratio of TRP/KYN in plasma is a valuable measure for IDO/TDO activity and the prognosis of disease conditions. The 4-vinylphenylboronic acid (4-VPBA) was evaluated as a novel stationary phase for OT-CEC-MS/MS. TRP, KYN, and 3-hydroxykynurenine were separated using optimum conditions of 15mM (NH4 )2 CO3 at pH 8 as a background electrolyte and 25kV separation voltage on a 90cm column. The usefulness of the 4-VPBA column for simple, fast, repeatable, and sensitive CEC-ESI-MS/MS application was demonstrated for the quantitation of TRP and KYN in the plasma of healthy human subjects and neuroinflammation subjects. The plasma sample was extracted on a zirconia-based ion-exchange cartridge for simultaneous protein precipitation and phospholipid removal. The method of standard addition, in combination with the internal standards approach, was used to prepare the calibration curve to overcome matrix matching and eliminate procedural errors. The developed quantitation method was validated according to FDA guidelines for sensitivity, accuracy, precision, and extraction recovery. The measured plasma level of TRP and KYN in healthy humans is aligned with the human metabolome database for the same two metabolites.

Engineered reversible adhesive biofoams for accelerated dermal wound healing: Intriguing multi-covalent phenylboronic acid/cis-diol interaction

Development of wound dressings that not only have multiple advantages including good biocompatibility, barrier properties, adhesive properties, but also exhibit anti-bacterial, anti-infection, and promote cell adhesion, accelerated wound healing process, remains challenging in the skin tissue engineering. In this work, a noninvasive adhesive biofoam with interconnectivity structure and antibacterial property was first-time designed through solid surfactant stabilized high internal phase emulsion (HIPE) template, where bacteriostatic Zn-CuO@GO nanosheets dynamic assemble with 4-vinylphenylboronic acid at the oil/water interface as cooperative emulsifier. Taking advantage of the cooperative assembly of the PBA/Zn-CuO@GO, the biofoams display microfibrousity and interconnectivity to facilitate material-cellular interaction as well nutrient exchange, and can effectively inhibit the growth of E. coli and S. aureus. Meanwhile, phenylboronic acid functional groups not only endow biofoam reversible adhesive property though dynamic phenylboronic acid/cis-diol interaction, but also facilitate the rearrangement of Zn-CuO@GO nanosheets in more uniform way at emulsion interface. Taken together, the biofoams can strongly adhere to the wound bed reducing the risk of infection and accelerate earlier tissue regeneration, which exhibit great potential in bioengineering application.

Construction of pH-responsive nanoplatform from stable magnetic nanoparticles for targeted drug delivery and intracellular imaging

Currently, developing responsive hydrophobic drug delivery systems centered on magnetic nanoparticles is a promising approach for the efficient delivery of hydrophobic drugs to living cells. Here, an efficacious designed strategy was proposed to construct pH-responsive nanoplatform for targeted hydrophobic drug delivery based on the formation of surface-anchored targeting molecules on the surface of Fe3O4 @C via single electron transfer living radical polymerization (SET-LRP) method. First, we prepared polymer-modified Fe3O4 @C using 4-vinylphenylboronic acid (VB) and polyethylene glycol methyl ether methacrylate (PEGMA) as polymerized monomers and confirmed that Fe3O4 @C-VB-PEGMA had high biocompatibility and low cytotoxicity. Next, we prepared curcumin-containing Fe3O4 @C-VB-PEGMA-Cur nanoplatform with an encapsulation efficiency for Cur as high as 67.7%. Furthermore, the nanoplatform not only displayed pH-responsive release behaviors of Cur under different pH values (pH=7.2, 6.5, 5.4), but also can be effectively targeted into HepG2 cells. More importantly, the nanoplatform also exhibited effectively inhibiting the growth of HepG2 cells and continuously intracellular imaging by the targeted releasing of loaded Cur. It is envisaged that these findings are a step forward in the construction of pH-responsive platform as a tool for clinical hydrophobic drug delivery.

Synthetic Thermo-Responsive Terpolymers as Tunable Scaffolds for Cell Culture Applications.

The use of tailored synthetic hydrogels for in vitro tissue culture and biomanufacturing provides the advantage of mimicking the cell microenvironment without issues of batch-to-batch variability. To that end, this work focused on the design, characterization, and preliminary evaluation of thermo-responsive, transparent synthetic terpolymers based on N-isopropylacrylamide, vinylphenylboronic acid, and polyethylene glycol for cell manufacturing and in vitro culture applications. Polymer physical properties were characterized by FT-IR, 1H-NMR, DLS, rheology, and thermal-gravimetric analysis. Tested combinations provided polymers with a lower critical solution temperature (LCST) between 30 and 45 °C. Terpolymer elastic/shear modulus varied between 0.3 and 19.1 kPa at 37 °C. Cellular characterization indicated low cell cytotoxicity on NIH-3T3. Experiments with the ovarian cancer model SKOV-3 and Jurkat T cells showed the terpolymers’ capacity for cell encapsulation without interfering with staining or imaging protocols. In addition, cell growth and high levels of pluripotency demonstrated the capability of terpolymer to culture iPSCs. Characterization results confirmed a promising use of terpolymers as a tunable scaffold for cell culture applications.

Preparation of reversed-phase/boronate affinity mixed-mode restricted access materials with zwitterionic polymer outer layers and its extraction properties

High-selectivity and high-exclusion restricted access materials (RAMs) benefit the demands of complex biological samples. In this study, mixed-mode-adsorption RAMs bearing zwitterionic polymer brushes as their outer layers were proposed. The reversed-phase/bronate affinity (RP/BA) mixed-mode adsorption layers on the surface of the silica gel were first formed by surface-initiated atom transfer radical polymerization (SI-ATRP) employing styrene (St) and 4-vinylphenylboronic acid (4-VPBA) as comonomers Afterward, zwitterionic poly(sulfobetaine methacrylate, SBMA) was grafted via another SI-ATRP reaction to establish the external hydrophilic layer. The selectivity of the developed Sil@poly(St-co-4-VPBA)@poly(SBMA) RAMs was examined employing different analytes (benzenes, tetracyclines, neurotransmitters, β-agonists, and their structural analogs), the results revealed the preferential adsorption of substances bearing phenyl and cis-diol groups owing to the multiple interactions (hydrophobic, π-π and BA forces) caused by the RAMs with RP/BA mixed-mode adsorption mechanism. On the other hand, the synergistic effect of the strong-hydrophilicity and high-density zwitterionic poly(SBMA) could efficiently promote the exclusion of RAMs. Moreover, the experimental data revealed that > 99% of bovine serum albumin (BSA, 1 g L–1) could be excluded, although the tetracycline (50 µg L–1) was completely adsorbed, indicating the maximized adsorption capacity of the RAMs toward small molecules after the efficient exclusion of protein interference. Solid-phase extraction (SPE) employing the developed Sil@poly(St-co-4-VPBA)@poly(SBMA) RAM coupled with high-performance liquid chromatography (HPLC) was successfully employed to determine the tetracycline content of a milk sample. The established method exhibited satisfactory linearity (10–700 µg L–1), high recovery (93.1%–108.6%) and good precision (2.6%–8.4%). Finally, our proposed method for synthesizing RAMs could efficiently boost the adsorption selectivity and restricted access function of RAMs, thereby promoting their application in analyzing biological samples.

Boronic acid-containing polymeric nanomaterials via polymerization induced self-assembly as fructose sensor

Owing to the reversible binding to diols, investigation of a simple and scalable strategy for the building of boronic acid-containing materials for fructose sensor is highly desirable but still challenging. Here, polymerization induced self-assembly is introduced to synthesis of core-shell spherical nanomaterials with boronic acid-rich shell in one-pot. Poly(4-vinylphenylboronic acid) 39 - b -polystyrene 242 (PVPBA 39 - b -PS 242 ) nanospheres with the diameter of 135 nm and PVPBA 230 - b -PS 1275 nanospheres with the diameter of 527 nm are prepared by PISA of styrene with PVPBA as chain transfer agent in methanol/H 2 O. The sensing applications of these two nanospheres are investigated. The fluorescence detection of 8-hydroxyquinoline by PVPBA 39 - b -PS 242 nanospheres is realized with high sensitivity at the ppm level, which is more sensitive than PVPBA 39 chain. PVPBA- b -PS nanospheres/alizarin red S complex and PVPBA- b -PS nanospheres/quercetin complex are built as a specific and sensitive fluorescence probe for fructose. The detection limit (LOD) of PVPBA- b -PS/ARS complex achieves 42.6 nM, while the LOD of PVPBA-b-PS/QC achieves 1.83 nM. • Nanospheres with boronic acid-rich shell are synthesized by PISA and designed as sensors for detection of fructose. • Via the evaluation by 8-hydroxyquinoline, these core-shell nanoshperes show higher sensitivity than PVPBA chains. • The detection limit of PVPBA-b-PS/ARS complex achieves 42.6 nM for fructose, while that of PVPBA-b-PS/QC achieves 1.83 nM.

Fast exhaustive enrichment and electrochemical quantitative detection of anthocyanins from natural products by using dual responsive and dummy molecularly imprinted polymers

In this work, a new adsorbent was synthesized using dummy-template molecular imprinting technology, magnetic separation technology and pH-responsive technology, which was used to quickly enrich anthocyanins in fruit and detect with electrochemical methods. On the surface of magnetic particles, the molecularly-imprinted materials were synthesized by using quercetin as the dummy-template, 4-vinyl phenylboronic acid and methacrylic acid as the functional monomers. The microstructure was characterized by scanning electron microscopy, transmission electron microscope, Fourier transform infrared spectroscopy, N2 adsorption–desorption, thermal gravimetric analysis, vibrating sample magnetometer and X-ray photoelectron spectroscopy. Compared with structural analogue, dummy-template magnetic and pH-responsive molecularly imprinted polymers (DMMIPs) had shorter kinetic equilibrium time, higher selectivity and better adsorption capacity toward anthocyanins. The binding capacity and imprinting factor of the dummy molecularly imprinted polymer could reach 59.22 mg/g and 1.56, respectively. The anthocyanins’ content of blueberry and grape peel crude extracts were consistent with the reference reports.

Isoporous membrane with glucose mediated toughness and protein sieving prepared from novel block copolymers containing boronic acid moieties

Bio-responsiveness is widely found in organisms. Incorporation of this function to membranes is an effective way to endow membranes with new functionalities. In this work, phenylboronic acid groups were used as the glucose binding moieties to construct a novel block copolymer polystyrene-block-poly(4-vinylphenylboronic acid) (PS-b-P4VBA), which was observed to assemble easily into periodic nanostructures in annealed thin films due to strong immiscibility between PS and P4VBA segments. Isoporous membranes were then fabricated from this newly synthesized copolymer following the procedure of self-assembly combined with non-solvent induced phase separation (SNIPS). The prepared isoporous membrane was determined to show a notable glucose dependent permeability that was ascribed to the switch of P4VBA conformation when it was bonded with glucose molecules. This interpretation was demonstrated by the glucose tailored surface wettability and protein sieving. Moreover, the glucose was found to serve as a molecular binder for the P4VBA, and toughness of dried isoporous membranes increased by ∼4 times. The reason was ascribed to the formation of new linkage between glucose and P4VBA that was verified by X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy analysis. Our results prove that the binding between glucose and boronic acid can be used to regulate both the separation performance and mechanical strength for isoporous block copolymer membranes. As far as we know, this performance has been rarely achieved for such membranes before.

Synthesis of Glucose/Fructose Sensitive Poly(ethylene glycol) Methyl Ether Methacrylate Particles with Novel Boronate Ester Bridge Crosslinker and their Dye Release Applications.

In this study, it is aimed to develop glucose/fructose sensitive poly(ethylene glycol) methyl ether methacrylate (PEGMA) particles which can be employed in controlled drug delivery applications. For this purpose, a boric acid based crosslinker was synthesized using 4-vinylphenylboronic acid and its formation was confirmed by 1H-NMR and FT-IR analyses. Sugar-sensitive polymeric particles were then achieved using this crosslinker and PEGMA monomer in single step and surfactant free emulsion polymerization technique. Polymeric particles were characterized by DLS, SEM, and TEM in terms of size and morphology. In order to determine the sensitivity of the particles to sugar molecules, first Rhodamine B dye (as a model drug) loading experiments were performed. Then, the particles were subjected to glucose/fructose rich media and dye release was monitored as a function of time using UV-Vis spectrophotometry. The results of the current study revealed that the PEGMA particles were more sensitive to fructose (~39% release) compared to glucose (~25% release) at pH 7.4 and 310 K.