Hydrophilic molecularly imprinted lysozyme-BiOBr composite with enhanced visible light utilization for selective removal of trace contaminants in water.

The development of high-efficiency molecularly imprinted photocatalysts is still challenging due to the lack of hydrophilic and suitable functional monomers. In this work, the bio-sourced lysozyme was developed as the hydrophilic functional monomer, and Cu-doped BiOBr was used as the photocatalysts, to prepare a novel hydrophilic molecularly imprinted lysozyme-BiOBr composite (BiOBr-Cu/LyzMIP) with enhanced visible light utilization. Lysozyme could form a transparent layer to mitigate the light transmission obstruction caused by the surface imprinting layer, making it an ideal functional monomer. The prepared BiOBr-Cu/LyzMIP possessed red-shifted visible-light absorption edge and minor reduction of light absorbance, indicating the enhanced utilization of visible light. Accordingly, BiOBr-Cu/LyzMIP demonstrated excellent degradation rate (99.4 % in 20 min), exceptional degradation efficiency (0.211 min-1), and superior reusability. Moreover, BiOBr-Cu/LyzMIP exhibited rapid adsorption equilibrium (20 min), good imprinting factor (2.67), and favourable degradation selectivity (>1.75), indicating the good imprinting effect resulting from abundant functional groups of lysozyme. Versatility experiments on different templates suggested that the proposed approach allowed flexibility in selecting a wide range of hazardous contaminants according to practical requirements. The present work expands the application of lysozyme-based composites in the environmental field, and provides a new one-stop pathway for efficient and sustainable treatment of contaminated water.

Land potential assessment and trend-analysis using 2000-2021 FAPAR monthly time-series at 250 m spatial resolution.

The article presents results of using remote sensing images and machine learning to map and assess land potential based on time-series of potential Fraction of Absorbed Photosynthetically Active Radiation (FAPAR) composites. Land potential here refers to the potential vegetation productivity in the hypothetical absence of short-term anthropogenic influence, such as intensive agriculture and urbanization. Knowledge on this ecological land potential could support the assessment of levels of land degradation as well as restoration potentials. Monthly aggregated FAPAR time-series of three percentiles (0.05, 0.50 and 0.95 probability) at 250 m spatial resolution were derived from the 8-day GLASS FAPAR V6 product for 2000-2021 and used to determine long-term trends in FAPAR, as well as to model potential FAPAR in the absence of human pressure. CCa 3 million training points sampled from 12,500 locations across the globe were overlaid with 68 bio-physical variables representing climate, terrain, landform, and vegetation cover, as well as several variables representing human pressure including: population count, cropland intensity, nightlights and a human footprint index. The training points were used in an ensemble machine learning model that stacks three base learners (extremely randomized trees, gradient descended trees and artificial neural network) using a linear regressor as meta-learner. The potential FAPAR was then projected by removing the impact of urbanization and intensive agriculture in the covariate layers. The results of strict cross-validation show that the global distribution of FAPAR can be explained with an R2 of 0.89, with the most important covariates being growing season length, forest cover indicator and annual precipitation. From this model, a global map of potential monthly FAPAR for the recent year (2021) was produced, and used to predict gaps in actual vs. potential FAPAR. The produced global maps of actual vs. potential FAPAR and long-term trends were each spatially matched with stable and transitional land cover classes. The assessment showed large negative FAPAR gaps (actual lower than potential) for classes: urban, needle-leave deciduous trees, and flooded shrub or herbaceous cover, while strong negative FAPAR trends were found for classes: urban, sparse vegetation and rainfed cropland. On the other hand, classes: irrigated or post-flooded cropland, tree cover mixed leaf type, and broad-leave deciduous showed largely positive trends. The framework allows land managers to assess potential land degradation from two aspects: as an actual declining trend in observed FAPAR and as a difference between actual and potential vegetation FAPAR.

Strategic preparation of porous magnetic molecularly imprinted polymers via a simple and green method for high-performance adsorption and removal of meropenem.

In this study, a facile method has been developed to synthesize a novel type of porous magnetic molecularly imprinted polymers (Fe3O4-MER-MMIPs) for the selective adsorption and removal of meropenem. The Fe3O4-MER-MMIPs, with abundant functional groups and sufficient magnetism for easy separation, are prepared in aqueous solutions. The porous carriers reduce the overall mass of the MMIPs, greatly improving their adsorption capacity per unit mass and optimizing the overall value of the adsorbents. The green preparation conditions, adsorption performance, and physical and chemical properties of Fe3O4-MER-MMIPs have been carefully studied. The developed submicron materials exhibit a homogeneous morphology, satisfactory superparamagnetism (60 emu g-1), large adsorption capacity (11.49 mg g-1), quick adsorption kinetics (40 min), and good practical implementation in human serum and environmental water. Finally, the protocol developed in this work delivers a green and feasible method for synthesizing highly efficient adsorbents for the specific adsorption and removal of other antibiotics as well.

Facile synthesis of hyperbranched magnetic nanomaterials for selective adsorption of proteins.

The separation and purification of proteins is an essential precondition for proteomics research because of the intricate matrix environment. Hence, a facile method has been developed to synthesize hyperbranched polyethyleneimine modified magnetic nanomaterials (Fe3O4-NH2-BPEI) with dendritic structure, unique electrostatic effect, and abundant functional groups for the selective adsorption of proteins which greatly avoids the drawbacks of time consumption and leakage of metal ions in traditional pre-treatment. The preparation conditions, physical and chemical properties, and adsorption performance of Fe3O4-NH2-BPEI have been fully studied. The obtained materials have stable crystal shape, adequate superparamagnetism, fast adsorption kinetics, high adsorption amount, and admirable reusability. In addition, the as-prepared Fe3O4-NH2-BPEI exhibits good selective adsorption ability for electronegative proteins in the neutral solution, exhibiting a potential value for special adsorption for proteins with different pI.

Aggregation and Binding-Directed FRET Modulation of Conjugated Polymer Materials for Selective and Point-of-Care Monitoring of Serum Albumins.

Nonspecific interactions of conjugated polymers (CPs) with various proteins prove to be a major impediment for researchers when designing a suitable CP-based probe for the amplified and selective recognition of particular proteins in complex body fluids. Herein, a new strategy is presented for the precise and specific monitoring of clinically important serum albumin (SA) proteins at the nanomolar level using fluorescence resonance energy transfer (FRET)-modulated CP-surfactant ensembles as superior sensing materials. In brief, the newly designed color-tunable CP PF-DBT-Im undergoes intense aggregation with the surfactant sodium dodecyl sulfate (SDS), enabling drastic change in the emission color from violet to deep red due to intermolecular FRET. The emission of PF-DBT-Im/SDS ensembles then changed from deep red to magenta specifically on addition of SAs owing to the exclusive reverse FRET facilitated by synergistic effects of electrostatic interactions, hydrophobic forces, and the comparatively high intrinsic quantum yield of SAs. Interestingly, PF-DBT-Im itself could not differentiate SAs from other proteins, demonstrating the superiority of the PF-DBT-Im/SDS self-assembly over PF-DBT-Im. Finally, an affordable smartphone-integrated point-of-care (PoC) device is also fabricated as a proof-of-concept for the on-site and rapid monitoring of SAs, validating the potential of the system in long-term clinical applications.

Multi-stimuli responsive molecularly imprinted nanoparticles with tailorable affinity for modulated specific recognition of human serum albumin.

A kind of novel multi-stimuli responsive molecularly imprinted polymers with bovine serum albumin (BSA) as a dummy template (MSR-BSA-MIPs) was fabricated for specific recognition of human serum albumin (HSA) with modulated affinity. The MSR-BSA-MIPs were prepared through free radical polymerization using vinyl modified magnetic nanoparticles as substrates, bovine serum albumin (BSA), with high amino acid sequence similarity but low price compared to HSA, as the dummy template, N-(3-(dimethylamino)-propyl)-methacrylamide (DMAPMA) and N-isopropylacrylamide (NIPAm) as functional monomers with ionic strength and temperature response. The conditions of polymerization, adsorption and elution were systematically investigated. As expected, the obtained MSR-BSA-MIPs exhibited rapid dispersion or separation states under magnetic control, flexible conversion of adsorption and desorption for the target protein under temperature or ionic strength adjustment. Ten adsorption-desorption cycles were carried out with a little decrease in adsorption capacity under two different elution methods, which also inspired us to combine two elution methods while considering both the stability and adsorption capacity of MSR-BSA-MIPs. The adsorption capacity (Q) and imprinting factor (IF) of MSR-BSA-MIPs for HSA are 43.01 mg g-1 and 4.26, respectively. Furthermore, the blood was opted as a realistic specimen for evaluating the adsorption capability of the proposed adsorbent, emphasizing its good practicality for target protein recognition and enrichment.

Conjugated polymer nanoparticles and their nanohybrids as smart photoluminescent and photoresponsive material for biosensing, imaging, and theranostics.

The emergence of conjugated polymers (CPs) has provided a pathway to attain smart multifunctional conjugated polymer nanoparticles (CPNs) with enhanced properties and diverse applications. CPNs based on π-extended CPs exhibit high fluorescence brightness, low cytotoxicity, excellent photostability, reactive oxygen species (ROS) generation ability, high photothermal conversion efficiency (PCE), etc. which endorse them as an excellent theranostic tool. Furthermore, the unique light-harvesting and energy transfer properties of CPNs enables their transformation into smart functional nanohybrids with augmented performance. Owing to such numerous features, simple preparation method and an easy separation process, the CPNs and their hybrids have been constantly rising as a frontrunner in the domain of medicine and much work has been done in the respective research area. This review summarizes the recent progress that has been made in the field of CPNs for biological and biomedical applications with special emphasis on biosensing, imaging, and theranostics. Following an introduction into the field, a first large section provides overview of the conventional as well as recently established synthetic methods for various types of CPNs. Then, the CPNs-based fluorometric assays for biomolecules based on different detection strategies have been described. Later on, examples of CPNs-based probes for imaging, both in vitro and in vivo using cancer cells and animal models have been explored. The next section highlighted the vital theranostic applications of CPNs and corresponding nanohybrids, mainly via imaging-guided photodynamic therapy (PDT), photothermal therapy (PTT) and drug delivery. The last section summarizes the current challenges and gives an outlook on the potential future trends on CPNs as advanced healthcare material.

Magnetic imprinted nanoparticles with synergistic tailoring of covalent and non-covalent interactions for purification and detection of procyanidin B2.

A synergistic imprinting strategy of covalent and non-covalent interactions is proposed to prepare magnetic molecularly imprinted polymers (DI-MMIPs) for highly selective separation of procyanidin B2 (PC) from grape seed samples. Dopamine and 3-amino-phenylboronic acid as cooperative functional monomers endow the imprinted sites with synergistic tailoring. Benefiting from the synergistic effect, the DI-MMIPs exhibit enhanced imprinting performance with high adsorption capacity (27.71 mg g-1), fast kinetic equilibrium time (within 30 min), outstanding selectivity (IF = 5.8, SC > 3.2), and satisfactory regeneration ability. In addition, the DI-MMIPs possess good magnetism, uniform morphology with typical core-shell structure, and stable crystallization. Furthermore, the established DI-MMIPs coupled with HPLC-UV (~ 280 nm) method has a wide linearity range of 0.05-200 µg mL-1 with correlation coefficient of 0.9997, high recoveries (> 93.1%) with RSDs from 2.9 to 5.5%, and low LOD (0.0008 µg mL-1). Consequently, this work provides an effective and easily tailored way to fabricate magnetic imprinted nanomaterials with both rapid recognition rate and high selectivity and thus holds great promise to realize the extraction and detection of PC from real samples.

Hydrophilic magnetic molecularly imprinted nanobeads for efficient enrichment and high performance liquid chromatographic detection of 17beta-estradiol in environmental water samples.

Novel magnetic molecularly imprinted nanobeads for 17ß-estradiol (E2), namely, E2-MMINs, were synthesized by molecularly imprinted polymers on the surface of magnetic nanobeads in aqueous solvents. The hydrophilic nanobeads were set up by adopting carboxyl group-functionalized Fe3O4 nanoparticles as carriers, E2 as template molecule, and dopamine as functional monomer. The synthesized E2-MMINs were investigated in different aspects including synthesis conditions, physical and chemical properties, and adsorption conditions. The experimental results show that the E2-MMINs present not only thin imprinting layers, stable crystal form, and fast magnetic separation ability, but also rapid kinetics (20 min), high binding amount (41.48 mg g-1), satisfactory specificity (imprinting factor = 8.07), and favorable reusability (adsorption efficiency > 94.8% after reusing for 10 times). Moreover, the method employing E2-MMINs combined with high performance liquid chromatography for the specific enrichment and determination of trace E2 has been developed with the low LOD (0.008 µg L-1), and the application in environmental water samples has been proved. This work demonstrates that the proposed synthetic strategy is highly promising to the synthesis of hydrophilic nanobeads for efficient enrichment and detection of target molecule E2.