4-carboxyphenylboronic Acid Research Articles

Boosting electron transfer of Ti-MOFs via electron-deficient boron doping for high-efficiency photocatalytic nitrogen fixation

The rational manipulation of electron transfer in photocatalysts are essential for the photocatalytic nitrogen fixation. In this study, a boron (B)-doping strategy is proposed for boosting the electron transfer of MOF-based photocatalysts. A series of B-doped Ti-MOFs, NH2/B-MIL-125 (NBM), were synthesized by a facile one-pot hydrothermal method, in which NH2-MIL-125, 2-aminoterephthalic acid (NH2-H2BDC) as the organic ligand, was chosen as the model material and the second ligand 4-carboxyphenylboronic acid (CPBA) was employed as the B source. The B element in CPBA is successfully incorporated into the MOF skeleton by forming the B-O-Ti bonds. The electron-deficient B atom can accommodate more photogenerated electrons, which acts as a “high-speed bridge” between the metal and ligand, thus effectively increasing the electron further transferring along the ligand-metal charge transfer (LMCT) path. Consequently, the recombination of photogenerated carriers is inhibited, greatly enhancing the photocatalytic nitrogen fixation performance. The optimal NBM sample exhibits an NH3 generation rate of 286.4 μmol g−1 L−1 under full spectrum, which is 2.9 times higher than that of pristine NH2-MIL-125 (73.4 μmol g−1 L−1). This study may provide a promising strategy to acquire high-efficiency photocatalysts via the electron-deficient element doping.

ROS-responsive injectable hydrogels loaded with exosomes carrying miR-4500 reverse liver fibrosis

The reversal of liver fibrosis requires effective strategies to reduce oxidative stress and inhibition of hepatic stellate cell (HSC) activation. MiR-4500 regulates pathological angiogenesis and collagen mRNA stability, with the potential to inhibit fibrosis. Herein, we explored the inhibition of HSC activation in vitro by exosomes (Exos) carrying miR-4500 and encapsulated ExosmiR−4500 in an intelligent injectable hydrogel with biological activity and reactive oxygen species (ROS) responsiveness for application in oxidative stress environments. Briefly, reversible boronic ester bonds were integrated into gelatin-based hydrogels through dynamic crosslinking of quaternized chitosan (QCS) and 4-carboxyphenylboronic acid (CPBA)-modified gelatin. The QCS-CPBA-Gelatin (QCG) hydrogel scavenged excess ROS from the local microenvironment and released ExosmiR−4500 through the dissociation of boronic ester bonds, providing a favorable microenvironment and in situ sustained-release drug delivery system for ExosmiR−4500. The results showed that QCG@ExosmiR−4500 hydrogel has biocompatibility, biodegradability, and slow-release ability, which could effectively clear ROS and inhibit HSC activation and pathological angiogenesis in vitro and in vivo. Furthermore, transcriptome analysis suggests that the pharmacological mechanism of the QCG@ExosmiR−4500 hydrogel is mainly related to anti-oxidation, anti-angiogenesis, anti-fibrosis processes, and signaling pathways. Thus, our study demonstrates that an intelligently responsive ExosmiR−4500 delivery system based on injectable hydrogels is a promising strategy for the treatment of liver fibrosis.

Synthesis, Properties, and Biocompatibility of 4-Carboxyphenyboronic Acid-Modified Gelatin-Methacryloyl: A Hydrogel for Retinal Surgeries.

The current surgical adjunctive for vitreoretinal surgeries fails to provide an adequate 3D structure for cellular regeneration. A one-pot synthesis of gelatin-methacryloyl (GelMA) followed by modification with 4-carboxyphenylboronic acid (4-CPBA) was performed to fabricate 4-CPBA-modified GelMA (4CPBA@GelMA), a gelatin-based hydrogel. 4CPBA@GelMA was photo-cross-linked by 405 nm violet light and examined using nuclear magnetic resonance (NMR), Fourier-transform infrared spectrometry (FTIR), scanning electron microscopy (SEM), and rheometry. In vitro biocompatibility was examined by Müller cell proliferation assays exposed to 4CPBA@GelMA and violet light. In vivo retinal biocompatibility was evaluated by electroretinography of rat eyes that were exposed to intravitreally injected and photo-cross-linked 4CPBA@GelMA at days 3, 7, 14, and 28 post-injection. Following electroretinography, histology and immunohistochemistry were performed on the retinas. The NMR results indicated amidation of GelMA by 4-CPBA, and FTIR confirmed the presence of the CPBA ring in 4CPBA@GelMA samples. SEM revealed that 4CPBA@GelMA had significantly larger pores than GelMA (56.9 ± 9.5 vs 35.1 ± 2.8 μm; P < 0.001). Rheological findings showed that, unlike GelMA and gelatin, 4CPBA@GelMA has Newtonian fluid properties at room temperature. Exposure to 4CPBA@GelMA did not significantly affect Müller cell viability in a proliferation assay; moreover, electroretinography findings indicated normal waveforms and implicit times, and histology and immunohistochemistry examinations revealed no significant changes. In this study, we established the high retinal compatibility of 4CPBA@GelMA. The low viscosity of 4CPBA@GelMA is ideal for injection via small-gauge needles, and the larger pore size and three-dimensional network both potentiate cellular migration and growth. These features made 4CPBA@GelMA a candidate for vitreoretinal surgical adjunctive that might promote retinal regeneration.

Self-powered wearable remote control system based on self-adhesive, self-healing, and tough hydrogels

The advent of the fifth-generation mobile communication network era induces a great potential for the design and development of self-powered wearable electronic devices. Hydrogels, as a typical material for flexible electrodes, have been widely employed in self-powered wearable electronic devices. However, the hydrogel-based triboelectric nanogenerator (H-TENG) is usually compromised by the challenges in data collection, operational stability, and manufacturability due to the unstable combination between the friction layer and the electrode layer, the occurrence of hydrogel damage during prolonged operation, and also the difficulty of machining sticky hydrogel electrodes. In the present study, a composite hydrogel composed of acrylamide, crotonyl alcohol, and 4-carboxyphenylboronic acid was synthesized via ultraviolet crosslinking, which was specially developed for H-TENG and wearable wireless remote control interface, featuring with excellent stretchability and mechanical strength as well as self-healing and self-adhesive properties. The open-circuit voltage of the H-TENG prepared with the hydrogel reached up to 165 V, and the output voltage remained almost unchanged following 10,000 cycles of compression test. Additionally, a wearable wireless remote control system was designed that could accurately control the multiple appliances and adjust different working modes using the H-TENG. Consequently, the development of the H-TENG and wearable wireless remote control system has the potential to provide a new methodology for the application of next-generation wearable devices in various areas, such as smart homes, as a representative example.

Dynamic borate ester bond reinforced hydroxyethyl cellulose/corn starch crosslinked film for simple recycling and regeneration

Endowing biodegradable plastics with easy recyclability can reduce competition with food resources and further enhance their environmental friendliness. In this work, 4-carboxyphenylboronic acid was grafted onto the side chains of hydroxyethyl cellulose and compounded with inexpensive cornstarch. Upon the introduction of tannic acid, stable and reversible borate ester bond rapidly formed, yielding composite biodegradable plastic films with outstanding mechanical properties and facile recyclability. The formation of a dynamic cross-linked network mitigates the aggregation of gelatinized starch molecules, enhancing the flexibility and durability of the crosslinked film. Testing revealed that while maintaining high tensile strength, the elongation at break of the crosslinked film increased by 952.86 %. The static water contact angle was improved from 32.74° to 78.82°, with a change of <5° within 1 min, demonstrating enhanced water resistance. Excellent antioxidant and thermal stability were also characterized, the crosslinked film can be easily dissolved by heating in water at pH = 6.5 and reshaped in water at pH = 7.2. After five times of regeneration, the tensile strength loss was as low as 5.68 %. This eco-friendly and efficient recycling process is promising during green chemistry.

Chitosan/rutin multifunctional hydrogel with tunable adhesion, anti-inflammatory and antibacterial properties for skin wound healing

Effective wound care remains a significant challenge due to the need for infection prevention, inflammation reduction, and minimal tissue damage during dressing changes. To tackle these issues, we have developed a multifunctional hydrogel (CHI/CPBA/RU), composed of chitosan (CHI) modified with 4-carboxyphenylboronic acid (CPBA) and the natural flavonoid, rutin (RU). This design endows the hydrogel with body temperature-responsive adhesion and low temperature-triggered detachment, thus enabling painless removal during dressing changes. The CHI/CPBA/RU hydrogels exhibit excellent biocompatibility, maintaining over 97 % viability of L929 cells. They also demonstrate potent intracellular free radical scavenging activity, with scavenging ratios ranging from 53 % to 70 %. Additionally, these hydrogels show anti-inflammatory effects by inhibiting pro-inflammatory cytokines (TNF-α, IL-6, and iNOS) and increasing anti-inflammatory markers (Arg1 and CD206) in RAW 264.7 macrophages. Notably, they possess robust antimicrobial properties, inhibiting over 99.9 % of the growth of Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus growth. In vivo testing on a murine full-thickness skin defect model shows that the hydrogel significantly accelerates wound healing by reducing inflammation, increasing collagen deposition, and promoting angiogenesis, achieving 98 % healing by day 10 compared to 78 % in the control group. These attributes make the polysaccharide-based hydrogel a promising material for advanced wound care.

Interaction of phenolic compounds with functionalized TiO2: Enhanced catechol adsorption and cooperative phenol adsorption

A commercial TiO2 sample functionalized with 3-aminopropyltrimethoxysilane (APTMS) and 4-carboxyphenylboronic acid (CPBA), has been previously proposed as a suitable photocatalyst to perform selective photocatalytic degradation of pollutants in aqueous streams, while avoiding the oxidation of valuable catechol simultaneously present in the reacting medium. In the present study, we highlight the adsorption mechanisms underlying the higher affinity of catechol, compared to phenol, with the surface of modified TiO2, quantitatively justifying the photocatalytic selective degradation results previously obtained. Moreover, a cooperative adsorption mechanism of phenol onto the TiO2 sample modified with APTMS has been for the first time observed. The resulting sigmoidal adsorption isotherms, satisfactorily fitted with the Hill model, could be attributed to the enhanced surface hydrophobicity and, more importantly, to alterations of the folding of APTMS molecules on the TiO2 surface occurring upon increasing the concentration of the phenolic compounds.Photocatalytic tests revealed that the existence of boronate groups on the surface of TiO2 hinders the photocatalytic degradation of catechol and facilitates a swifter oxidation of phenol. These findings confirm the potential for selective photocatalytic degradation, in line with modern conceptions of innovative and environmentally sustainable wastewater treatments.

Boronic Acid Functionalized Zirconium based MOF for the Complete Adsorptive Removal of Alizarin Dye

Nowadays, one of the severe problems that threaten the survival of human beings is water pollution. Water pollution caused by diverse poisonous compounds, specifically hydroxyl aromatic compounds and their derivatives have been evident and prominent environmental issue. In this work, an adsorptive method to remove the hydroxyl aromatic compounds particularly catechol based Alizarin red S dye by the activated metal organic framework have been attempted. The nano scale Zr-UiO-66 was synthesized using terephthalic acid as ligand, 4-carboxy phenyl boronic acid as coordination modulator and the morphology of the nano crystals was octahedral. The as-synthesized new metal organic framework Zr-UIO-66 after adsorption confirms the existence of boronic acid and structural stability after the incorporation of the boronic acid group using adsorption studies such as 11B NMR, PXRD, UV, IR and TGA. The zirconium based MOFs are very important in terms of their stability in water. These MOFs are largely used for gas separation, storage, sensing and degradation of chemical warfare agents, etc. The control of size of these MOFs to nano regime can be achieved using the monocarboxylic acids like acetic acid, benzoic acid. A mixed-ligand approach was implemented in this work.

Role of mesoporous silica functionalized with boronic acid derivative in targeted delivery of doxorubicin and co-delivery of doxorubicin and resveratrol

Phenylboronic acid derivatives have gained interest due to their ability to reversibly bind to 1,2-diols, such as sialic acid receptors overexpressed by breast cancer cells. In this study, two types of mesoporous silica, MCM-41 and SBA-15, were functionalized with 4-carboxyphenylboronic acid (CPBA) through the amidation reaction, and the resulting materials MCM-CPBA and SBA-CPBA were used as carriers for doxorubicin (Dox) or for co-delivery of doxorubicin and resveratrol. In the case of MCM-CPBA material, all amine groups were involved in the condensation reaction with boronic acid derivative, while in the case of SBA-CPBA, free amine groups remained on the silica surface. Dox release profiles, performed in phosphate buffer solution pH 5.5, showed a faster release kinetics of Dox and a higher cumulative drug release for co-delivery system. Larger pores of SBA-15-type carrier influenced the Dox release profile as the diffusion of drug molecules was favored, a higher cumulative drug release being obtained in the case of SBA-CPBA than for MCM-CPBA. Biological assessment of the developed drug delivery systems demonstrated lower cytotoxicity on BJ fibroblasts than on BT474 breast cancer cells. Evaluation of drug delivery systems by hyperspectral microscopy evidenced a higher internalization rate of Dox when was loaded on functionalized silica carriers compared to the free drug into BT474 cells. The internalization rate of doxorubicin-loaded carrier depended on the type of carrier; a better internalization was observed for cancer cells when were treated with Dox-loaded MCM-CPBA nanoparticles than for Dox-loaded SBA-CPBA that might be attributed to smaller size of MCM-CPBA nanoparticles.

Hydrogen bond-modulated copper nanocluster-aggregation-induced enhanced ECL with layered double hydroxides-sensing interface for miRNA-135b detection in colorectal cancer

Herein, we developed a novel electrochemiluminescence (ECL) sensing interface based on Mg/Fe layered double hydroxides nanosheets (LDHs) for miRNA-135b detection in human colorectal cancer tissues. The LDHs nanosheet with large specific surface area and abundant active sites can work as the electrode sensing interface to effectively catalyze the electrochemical reactions. Furthermore, the formation of hydrogen bonds between 4-carboxyphenylboronic acid (CBPA) on the copper nanoclusters (Cu NCs) and fluorine ions limited the intramolecular vibration and accelerated electron transfer, greatly improving the luminescence signal. Due to the catalysis of LDH and the aggregation-induced enhanced electrochemiluminescence (AIECL) effect, the ECL quantum yield of Cu NCs has been significantly amplified. The Mg/Fe LDH-based sensing system for miRNA-135b detection had a linear detection range of 10 fM–10 μM with a detection limit of 3.5 fM. Finally, the cancer tissue extracted from colorectal cancer patients have been successfully detected. The result indicated that the Mg/Fe LDHs sensing interface provided a new and reliable pathway for ECL analysis performance.

Detection of H2O2 and catalase on a paper-based flow sensor constructed with borate cross-linked PVA hydrogel

The detections of H2O2 and catalase play an important role in daily life. This study introduces a paper-based flow sensor that is specifically designed to detect H2O2 and catalase. The sensor utilizes a hydrogel composed of cross-linked 4-carboxyphenylboronic acid and polyvinyl alcohol. When H2O2 is in contact with the hydrogel, the B–C bonds of the hydrogel undergo a reactive process, causing decomposition of the hydrogel. The pH indicator strip enables the visual monitoring of the viscosity change that occurs during the gel-sol transition. The quantification of H2O2 is accomplished by assessing the proportion of water coverage on the pH indicator strip. The sensor shows a detection limit of 0.077 wt% and is applicable for the quantitative measurement of H2O2 in routinely used disinfectants. Furthermore, the presence of catalase is effectively identified and the detection of catalase in milk is successfully fulfilled. In summary, this work proposes a simple, user-friendly, label-free, and cost-effective method for constructing a paper-based flow sensor using borate cross-linked polyvinyl alcohol hydrogel, showing great potential for detecting H2O2 and catalase in various practical scenarios.

Nonenzymatic dual glucose sensing on boronic acid modified zeolitic imidazolate framework-67 nanoparticles for diabetes management.

For early diabetes identification and management, the progression of an uncomplicated and exceedingly responsive glucose testing technology is crucial. In this study, we present a new sensor incorporating a composite of metal organic framework (MOF) based on cobalt, coated with boronic acid to facilitate selective glucose binding. Additionally, we successfully employed a highly sensitive electro-optical immunosensor for the detection of subtle changes in concentration of the diabetes biomarker glycated haemoglobin (HbA1c), using zeolitic imidazolate framework-67 (ZIF-67) coated with polydopamine which further modified with boronic acid. Utilizing the polymerization characteristics of dopamine and the NH2 groups, a bonding structure is formed between ZIF-67 and 4-carboxyphenylboronic acid. ZIF-67 composite served as an effective substrate for immobilising 4-carboxyphenylboronic acid binding agent, ensuring precise and highly selective glucose identification. The sensing response was evaluated through both electrochemical and optical methods, confirming its efficacy. Under optimized experimental condition, the ZIF-67 based sensor demonstrated a broad detection range of 50-500mg dL-1, a low limit of detection (LOD) of 9.87mg dL-1 and a high correlation coefficient of 0.98. Furthermore, the 4-carboxyphenylboronic acid-conjugated ZIF-67-based sensor platform exhibited remarkable sensitivity and selectivity in optical-based detection for glycated haemoglobin within the clinical range of 4.7-11.3%, achieving a LOD of 3.7%. These findings highlight the potential of the 4-carboxyphenylboronic acid-conjugated ZIF-67-based electro-optical sensor as a highly sensitive platform for diabetes detection.

Synthesis of Bone Meal-derived 4-Carboxyphenylboronic Acid Functionalized Sulfur and Nitrogen Co-doped Graphene Quantum Dots Nanoprobe for Sialic Acid Sensing

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.

Achieving color-tunable persistent afterglow from ultralong polyacrylamide-based room-temperature phosphorescence materials through phosphorescence Förster resonance energy transfer

Polymer-based pure organic room-temperature phosphorescence (RTP) materials have received widespread attention due to their great application prospects in many fields. However, the reports about polymer-based multicolor RTP materials were still rare. Herein, a series of monochromatic PAM-based RTP materials are constructed by facilely doping boric acid derivatives into polyacrylamide (PAM) matrices. Due to the strong intermolecular hydrogen-bonding interaction, 4-carboxyphenylboronic acid (CPBA) doped system PAM/CPBA achieves an ultralong RTP lifetime of 753 ms with a naked-eye visible blue afterglow up to 12 s. Significantly, PAM/CPBA as energy donor and the commercial fluorescent dye fluorescein (FL) or rhodamine B (RhB) as energy acceptor are used to fabricated ternary doping systems to achieve multicolor afterglow emission through phosphorescence Förster resonance energy transfer (FRET). The afterglow colors of PAM/CPBA/FL and PAM/CPBA/RhB can be easily adjusted from blue to yellow or purple by changing the doping content of FL or RhB. Inspiringly, a nearly white afterglow emission from the quaternary doping system PAM/CPBA/RhB/FL is achieved by varying the amount of FL content. Furthermore, the prepared PAM-based binary and ternary doping RTP materials can be applied in the field of information encryption.

Enhancing anti-cancer potential by delivering synergistic drug combinations via phenylboronic acid modified PLGA nanoparticles through ferroptosis-based therapy

In this study, we investigated the potential of the sorafenib (SOR) and simvastatin (SIM) combination to induce ferroptosis-mediated cancer therapy. To enhance targeted drug delivery, we encapsulated the SOR + SIM combination within 4-carboxy phenylboronic acid (CPBA) modified PLGA nanoparticles (CPBA-PLGA(SOR + SIM)-NPs). The developed CPBA-PLGA(SOR + SIM)-NPs exhibited a spherical shape with a size of 213.1 ± 10.9 nm, a PDI of 0.22 ± 0.03, and a Z-potential of −22.9 ± 3.2 mV. Notably, these nanoparticles displayed faster drug release at acidic pH compared to physiological pH. In cellular experiments, CPBA-PLGA(SOR + SIM)-NPs demonstrated remarkable improvements, leading to a 2.51, 2.69, and 2.61-fold decrease in IC50 compared to SOR alone, and a 7.50, 16.71, and 5.11-fold decrease in IC50 compared to SIM alone in MDA-MB-231, A549, and HeLa cells, respectively. Furthermore, CPBA-PLGA(SOR + SIM)-NPs triggered a reduction in glutathione (GSH) levels, an increase in malondialdehyde (MDA) levels, and mitochondrial membrane depolarization in all three cell lines. Pharmacokinetic evaluation revealed a 2.50- and 2.63-fold increase in AUC0-∞, as well as a 1.53- and 2.46-fold increase in mean residence time (MRT) for SOR and SIM, respectively, compared to the free drug groups. Notably, the CPBA-PLGA(SOR + SIM)-NPs group exhibited significant reduction in tumor volume, approximately 9.17, 2.45, and 1.63-fold lower than the control, SOR + SIM, and PLGA(SOR + SIM)-NPs groups, respectively. Histological examination and biomarker analysis showed no significant differences compared to the control group, suggesting the biocompatibility of the developed particles for in-vivo applications. Altogether, our findings demonstrate that CPBA-PLGA(SOR + SIM)-NPs hold tremendous potential as an efficient drug delivery system for inducing ferroptosis, providing a promising therapeutic option for cancer treatment.

Synergistic anticancer therapy via ferroptosis using modified bovine serum albumin nanoparticles loaded with sorafenib and simvastatin

Ferroptosis is a non-apoptotic cell death pathway characterized by the accumulation of lipid-peroxy radicals within the affected cells. Here, we investigate the synergistic capacity of sorafenib (SOR) and simvastatin (SIM) to trigger ferroptosis for cancer therapy. For precise in-vivo delivery, SOR + SIM was ratiometrically loaded in bovine serum albumin nanoparticles (BSA-NPs) modified with 4-carboxy phenylboronic acid (CPBA). The developed CPBA-BSA(SOR + SIM)-NPs revealed size of 175.2 ± 12.8 nm, with PDI of 0.22 ± 0.03 and Z-potential of −29.6 ± 4.8 mV. Significantly, CPBA-BSA(SOR + SIM)-NPs exhibited > 2 and > 5-fold reduction in IC50 values compared to individual SOR and SIM treatments respectively, in all tested cell lines. Moreover, CPBA-BSA(SOR + SIM)-NPs treated cells exhibited decrease in glutathione levels, increase in malonaldehyde levels and depolarization of mitochondrial membrane potential (JC-1 assay). Pharmacokinetic analysis revealed enhanced AUC0-∞ and MRT levels for SOR and SIM when administered as CPBA-BSA(SOR + SIM)-NPs compared to free drugs. Crucially, in in-vivo experiments, CPBA-BSA(SOR + SIM)-NPs led to a significant reduction in tumor volume compared to various control groups. Histological and biomarker analyses underscore their biocompatibility for clinical applications. In conclusion, this study highlights the potential of CPBA-BSA(SOR + SIM)-NPs as a promising strategy for inducing ferroptosis in cancer cells, concurrently improving drug delivery and therapeutic efficacy. This approach opens new avenues in cancer treatment.

Formulation and evaluation of paclitaxel-loaded boronated chitosan/alginate nanoparticles as a mucoadhesive system for localized cervical cancer drug delivery.

Cervical cancer remains a significant global health challenge, and there is a need for innovative drug delivery systems to improve the efficacy of anticancer drugs. In this study, we developed and evaluated boronated chitosan/alginate nanoparticles (BCHIALG NPs) as a localized mucoadhesive drug delivery system for cervical cancer. Boronated chitosan (BCHI) was synthesized by incorporating 4-carboxyphenylboronic acid onto chitosan (CHI), and boronated chitosan/alginate nanoparticles (BCHIALG NPs) with varying polymer ratios were prepared using an ionic gelation method. The physical properties, drug loading capacity/encapsulation efficiency, mucoadhesive properties, and in vitro drug release profile of the nanoparticles were evaluated. The BCHIALG NPs exhibited a size of less than 390 nm and demonstrated high drug encapsulation efficiency (98.1 - 99.8%) and loading capacity (326.9 - 332.7 μg/mg). Remarkably, the BCHIALG NPs containing 0.03% boronated chitosan and 0.07% alginate showed superior mucoadhesive capability compared to CHIALG NPs, providing sustained drug release and they showed the most promising results as a transmucosal drug delivery system for hydrophobic drugs like paclitaxel (PTX). To the best of our knowledge, this is the first report investigating BCHIALG NPs for cervical drug delivery. The new mucoadhesive paclitaxel formulation could offer an innovative strategy for improving cervical cancer treatment.

Effect of selected green corrosion inhibitors on SO2 removal during carbon steel corrosion in aqueous solutions of ammonia and histidine

To understand the feasibility of using carbon steel in the flue gas desulfurization process, the corrosion protection of carbon steel was investigated by adding four green corrosion inhibitors (12-aminolauric acid; 4-carboxyphenylboronic acid; 1,2,3-benzotriazole; and L-methionine) to an ammonia solution containing histidine as the SO2 absorbent. The effects of the corrosion inhibitors on the corrosion rates of carbon steel and SO2 absorption performance were investigated. We observed that 1,2,3-benzotriazole was the most effective corrosion inhibitor, reducing the corrosion rate by 73 % and increasing the SO2 absorption loading by 8.3 % compared to other corrosion inhibitors. Scanning electron microscopy/energy dispersive X-ray spectroscopy and X-ray diffraction studies were conducted to understand the corrosion inhibition behavior of 1,2,3-benzotriazole. The formation of the Fen-(SO2-BTA)m complex and its subsequent adsorption on the carbon steel surface blocked active sites and inhibited corrosion. This study demonstrated the feasibility of effectively using carbon steel under harsh environmental conditions such as in desulfurization.

Tunable ultralong multicolor and near-infrared emission from polyacrylic acid-based room temperature phosphorescence materials by FRET

Polymer-based room temperature phosphorescence (RTP) materials have received significant attention for their potential application in various fields. However, the development of polymer-based RTP materials with persistent multicolor and near-infrared (NIR) emission still faces great challenges. Herein, 4-carboxyphenylboronic acid (CPBA) is facilely doped into polyacrylic acid (PAA) matrix to construct an ultralong RTP material PAA-CPBA, which is the better candidate of energy donor owing to the wide phosphorescence emission band. Two commercial fluorescent dyes rhodamine B (RhB) and fluorescein (FL) are selected as energy acceptors to prepared ternary systems PAA-CPBA-RhB and PAA-CPBA-FL, and tunable multicolor afterglow from blue to red and yellow is realized through phosphorescence Förster resonance energy transfer (FRET). More interestingly, the quaternary doping system PAA-CPBA-RhB-FL exhibits a nearly white afterglow emission. Significantly, a commercial NIR dye Nile blue (NiB) is used to fabricate the other quaternary doping systems PAA-CPBA-RhB-NiB, and persistent luminescence in NIR region is successfully achieved via stepwise FRET using RhB as an intermediate acceptor. Furthermore, due to the different persistent luminescence performance, the multicolor PAA-based RTP materials are successfully applied in multiple information encryption and multicolor displays.

Amine-stabilized boronate groups at the surface of modified TiO2 under circumneutral pH conditions: Application to selective photocatalytic degradations

TiO2 has been functionalized by using 3-aminopropyltrimethoxy silane (APTMS) and 4-carboxyphenylboronic acid (CPBA). Solid state NMR indicated that ca. 50% of the amino groups did not react with CPBA, and stabilized vicinal boronate groups even at circumneutral pH, i.e. outside the stability range of isolated boronate ions (pH > 8.8). The as demonstrated existence of stabilized boronate groups at circumneutral pH has been used to carry out the proof of concept for selective photocatalytic degradations. In particular, irradiating bare TiO2 induced the expected oxidation of two model pollutants (alizarin red, AR and methylene blue, MB) dissolved in the reacting medium. Instead, the presence of boronate groups at the surface of TiO2 prevented the photocatalytic degradation of adsorbed AR, while simultaneously allowing oxidation of MB. Results are of environmental interest, and pave the way to processes enabling recovery of valuable compounds and simultaneous photocatalytic degradation of other noxious and/or useless species present in the same stream.