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[Display omitted] • A polyethersulfone/sulfonated polysulfone loose NF membrane was fabricated. • The membrane exhibited high flux and enhanced selectivity of PPCPs/minerals. • The removal of ionic PPCPs is mainly dominated by charge exclusion and adsorption. • Non-ionizable PPCPs are removed by adsorption and size exclusion. Nanofiltration (NF) membranes have a high removal rate for pharmaceutical and personal care products (PPCPs) in drinking water, but they also reject critical minerals (e.g., calcium and magnesium) that are beneficial to health. Herein, polyethersulfone (PES)/sulfonated polysulfone (SPSf) loose NF membranes were fabricated using non-solvent induced phase separation (NIPS) to enable efficient rejection of PPCPs while preserving high mineral permeability. The resultant loose NF membrane showed increased negative charge owing to the -SO 3 - groups of SPSf. It also exhibited a high water permeance of ∼20.8 L m-2 h−1 bar−1 characterized by high PPCPs/minerals selectivity (i.e. , rejection of PPCPs > 90 % and rejection of Mg2+ < 5 %). The filtration performance of resultant membrane indicated that the ionic PPCPs (e.g., Indomethacin, Diclofenac Sodium, Levofloxacin, Norfloxacin) were removed by the electrostatic repulsion and adsorption, while the removal of non-ionic PPCPs (e.g., Bisphenol A, Carbamazepine) was primarily dominated by the synergy of adsorption and size exclusion. Therefore, the superior removal rate of hydrophilic PPCPs was due to enhanced PPCP-membrane adsorptive interaction. This study provides a profound understanding of the selective separation mechanism of loose NF membranes for micropollutants and minerals. [ABSTRACT FROM AUTHOR]

In the synthesis of the polyamide nanofiltration (NF) membrane, the hydrogen chloride is a by-product generated at the organic interface from interfacial polymerization, which reduces the reactivity of amine monomers due to protonation. Herein, a strategy of addition of an organic base in the organic phase to neutralize the H+ was reported. The performances of the membranes produced using three organic bases with different chain lengths were explored. The results showed that the organic base neutralized the H+ and promoted the rate of interfacial condensation reaction, which facilitated the formation of a dense and thin polyamide layer. Moreover, compared to control membrane, the membrane modified by organic base exhibited higher water permeance without sacrificing salt rejection. Higher diffusion rate of HCl through PES substrate compared to NF membrane indicated that HCl diffusion was mainly affected by the resistance of polyamide layer. Molecular simulations demonstrated that triethylamine (TEA) has lower energy barrier of neutralization and higher reaction heat in comparison with tripropylamine and N, N-diisopropylethylamine. The TEA modified membrane thereby displayed a permeance up to 24.3 L h−1 m−2 bar−1 and Na 2 SO 4 rejection of 98.8 %. This work provided a promising strategy for the regulation of interfacial polymerization in achieving high-permselective nanofiltration. [Display omitted] • Adding organic base into organic phase could in-situ neutralize generated HCl. • Organic base modified membrane exhibited a thinner polyamide layer. • The polyamide layer inhibited HCl diffusion resulting in decreased neutralization. • The neutralization between TEA and HCl has lower energy and higher reaction heat. [ABSTRACT FROM AUTHOR]

Starch is the major form of carbohydrate storage in plants and exists as discrete starch granules (SGs). Isolation of high‐quality SGs in different plant tissues is a prerequisite for studying the roles of SGs during plant growth, development, and responses to abiotic stress. However, it is difficult to isolate transitory SGs from leaves and storage SGs from pollen grains due to their small sizes and low quantities. Herein, we develop a novel method for isolating SGs by using the aqueous two‐phase system (ATS) of ethanol/NaH2PO4. The ATS method efficiently separated SGs from contaminants based on their differences in density, solubility, and polarity. Using this method, we first isolated and purified three kinds of SGs from maize seeds, pollen, and leaves. The biochemical, microscopic, and proteomic analyses demonstrated the high purity of the isolated SGs. Proteomic analysis revealed distinct differences in SG‐bound proteins between seed SGs and pollen SGs. As a simple, rapid, and low‐cost method, the ATS‐based method exhibits highly universal and reproducible results for starch‐containing tissues in various plant species. We develop a novel and universal method for isolating starch granules (SGs) by use of an aqueous two‐phase system. The method allows to isolate even small quantities of transitory SGs in leaves and storage SGs in pollen. [ABSTRACT FROM AUTHOR]

Abstract: Photodynamic therapy (PDT) is an emerging clinical modality for the treatment of a variety of diseases. Most photosensitizers are hydrophobic and poorly soluble in water. Many new nanoplatforms have been successfully established to improve the delivery efficiency of PS drugs. However, few reported studies have investigated how the carrier microenvironment may affect the photophysical properties of photosensitizer (PS) drugs and subsequently, their biological efficacy in killing malignant cells. In this study, we describe the modulation of type I and II photoactivation processes of the photosensitizer, 5,10,15,20-tetrakis(meso-hydroxyphenyl)porphyrin (mTHPP), by the micelle core environment. Electron-rich poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) micelles increased photoactivations from type II to type I mechanisms, which significantly increased the generation of O2 − through the electron transfer pathway over 1O2 production through energy transfer process. The PDPA micelles led to enhanced phototoxicity over the electron-deficient poly(d,l-lactide) control in multiple cancer cell lines under argon-saturated conditions. These data suggest that micelle carriers may not only improve the bioavailability of photosensitizer drugs, but also modulate photophysical properties for improved PDT efficacy. [Copyright &y& Elsevier]

Abstract: Nanodelivery systems have shown considerable promise in increasing the solubility and delivery efficiency of hydrophobic photosensitizers for photodynamic therapy (PDT) applications. In this study, we report the preparation and characterization of polymeric micelles that incorporate protoporphyrin IX (PpIX), a potent photosensitizer, using non-covalent encapsulation and covalent conjugation methods. Depending on the incorporation method and PpIX loading percentage, PpIX existed as a monomer, dimer or aggregate in the micelle core. The PpIX state directly affected the fluorescence intensity and 1O2 generation efficiency of the resulting micelles in aqueous solution. Micelles with lower PpIX loading density (e.g. 0.2%) showed brighter fluorescence and higher 1O2 yield than those with higher PpIX loading density (e.g. 4%) in solution. However, PDT efficacy in H2009 lung cancer cells showed an opposite trend. In particular, 4% PpIX-conjugated micelles demonstrated the largest PDT therapeutic window, as indicated by the highest phototoxicity and relatively low dark toxicity. Results from this study contribute to the fundamental understanding of nanoscopic structure–property relationships of micelle-delivered PpIX and establish a viable micelle formulation (i.e. 4% PpIX-conjugated micelles) for in vivo evaluation of antitumor efficacy. [Copyright &y& Elsevier]

Maize starch is an important agricultural commodity that serves as food, feed, and a raw material for industrial purposes. Starch biosynthesis in maize endosperm is an essential process for maize productivity under changing environmental conditions. However, the molecular mechanism underlying starch synthesis during maize endosperm development remains largely unknown. Recently, proteomic analyses of starch synthesis in maize seeds have produced large amounts of data, which significantly add to our understanding of maize starch biosynthesis and facilitate knowledge‐based maize improvements. In this review, the current knowledge on starch biosynthesis in maize endosperm is introduced, key aspects of protein extraction for proteomic analysis of maize starch biosynthesis are discussed, and the recent proteomic findings are summarized. A model outlining the roles of specific enzymes is then proposed. The important role of proteomics in identifying the key proteins involved in starch biosynthesis is highlighted in order to further the understanding of the complex mechanisms underlying maize starch biosynthesis. [ABSTRACT FROM AUTHOR]

Loose nanofiltration membrane is regarded as an effective separation technology for dye purification and reuse, but is still restrained by the trade-off between the permeance and the dye/salts selectivity. Herein, we report the fabrication of an ultrafast loose polyamide nanofiltration (NF) membrane on the nanofibrous support layer with uniform in-situ grown ZnO nanoparticles. It was found that embedding ZnO nanoparticles provides more water channels and increased effective filtration area, thus enhancing the water permeation without trading off the dye/salt selectivity. The fabricated NF membrane with an in-situ formed ZnO-nanoparticle interlayer exhibits an ultrahigh water permeance up to 375 L m−2 h−1 bar−1, which increased by approximate seven-fold than that of virgin NF membrane (54 L m−2 h−1 bar−1) without nanoparticles intercalated, and attains high rejection of organic dyes (>91 % for Congo red, >92 % for Methyl blue, and >98 % for Victoria blue B) but low rejection of inorganic salts (<5 %). The synergy of steric exclusion and charge effect dominate the high selectivity of dye and salts. This study unlocks a new avenue to synthesize ultrahighly permeable-selective loose NF membranes. [Display omitted] • Loose nanofiltration membrane was fabricated on the nanofibrous substrates. • ZnO nanoparticles were in-situ grown uniformly on the surface of nanofibers. • ZnO nanoparticles regulated surface morphology and provided more water channels. • The membrane exhibited high flux and selectivity for dye/salts. [ABSTRACT FROM AUTHOR]

Nanofiltration (NF) membrane with good permselectivity is highly desired. However, it often suffers from permeability-selectivity trade-off in practical applications. To overcome this challenge, a novel in-situ template strategy was proposed for the preparation of high-performance thin film nanocomposite (TFN) NF membrane by adding AgNO 3 in the aqueous solution. The AgCl nanoparticles can be in-situ incorporated into the polyamide film due to the by-product of HCl from the interfacial polymerization and AgNO 3 at the oil/water interface. Besides, water transportation channels can be further constructed in the polyamide film via removal the AgCl template using ammonia as post-treatment solution. The optimized NF-3 membrane with low water transportation resistance shows a two-fold permeance as well as equal salt rejection compared with the controlled NF-1 membrane, indicating that the "trade-off" effect is effectively inhibited. Consequently, the in-situ template strategy provides a new sight for the preparation of high-performance NF membrane. [Display omitted] • A homogeneous addition - in-situ templating method was proposed to prepare NF membrane. • Silver nitrate was added in aqueous phase to in-situ generate silver chloride nanoparticles. • Water transportation channels was constructed by ammonia post-treatment. • The optimized membrane exhibits high water permeance and Na 2 SO 4 rejection. [ABSTRACT FROM AUTHOR]

In the preparation of nanofiltration (NF) membranes, the introduction of acid acceptors into the aqueous phase generates heat through their interaction with the byproduct HCl from interfacial polymerization (IP), potentially leading to the formation of bubbles. This work aims to dissect the combined influences of heat and nanobubbles on NF membrane structure and performance. Three representative alkalis (i.e., NaHCO 3 , NaOH, and Ca(OH) 2) were employed as acid acceptors into the aqueous phase, resulting in an increase of the consumption of PIP in the IP reaction from 10.75% to 23.65%, 19.35%, and 12.90%, respectively. The use of NaOH and Ca(OH) 2 released more heat led to a thicker polyamide layer which reduced flux. While the use of NaHCO 3 simultaneously released heat and bubbles, which promoted the development of a rougher surface polyamide layer, resulting in an increased flux from 20.3 to 28.3 L/m2 h bar, while maintaining a salt rejection rate of 97.7%. The attendance of acid acceptors also enhanced the degree of crosslinking and resulted in a decrease in negative charge of the prepared membrane. This study advances the understanding of the impact of heat and bubbles release induced by the addition of acid acceptors on NF membrane structure and performance. [Display omitted] • Acid acceptors in aqueous phase could promote interfacial polymerization. • Interfacial polymerization reactions can be half completed within 15 s. • Gas release has a great impact on NF membrane compared to generated heat. • NaHCO 3 exhibits the most significant promotional effect on IP process due to gas release. [ABSTRACT FROM AUTHOR]

To balance the permeability-selectivity trade-off effect of the polyamide nanofiltration membrane, interfacial polymerization regulation strategy is widely used to optimize the physicochemical structure of the polyamide film. In the present work, the compound additives of phytic acid and ferric chloride were added into the aqueous phase to regulate the interfacial polymerization process. On the one hand, a lot of piperazine monomers will be adsorbed around the phytic acid molecules due to the electrostatic interaction between phosphoric acid groups and amino groups. Meanwhile, the phytic acid molecules and ferric ions can form a complex in the piperazine solution, which results in a low diffusion rate of the other piperazine monomers without adsorbed on the phytic acid and ferric chloride complex due to steric hindrance. The synergistic effect of electrostatic interaction and steric hindrance leads to the optimized nanofiltration membrane with a thinner and looser polyamide structure. The best-performing nanofiltration membrane exhibits an approximately four-fold water permeance (28.4 L m−2 h−1 bar−1) compared with the controlled M0 nanofiltration membrane (6.5 L m−2 h−1 bar−1) without obviously sacrificing the Na 2 SO 4 rejection (96.9 %). This simple interfacial polymerization regulation strategy provides a novel insight for the preparation of high-performance NF membrane. Phytic acid&FeCl3 compound additives-regulated interfacial polymerization. [Display omitted] • Phytic acid and ferric chloride were employed to regulate interfacial polymerization. • The compound additives can inhibit piperazine monomer diffusion. • The nanofiltration membrane shows a thin and loose polyamide layer. • The optimized membrane exhibits high water permeance and Na 2 SO 4 rejection. [ABSTRACT FROM AUTHOR]

Abstract: This work reports a new sensitive multi-residue liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for detection, confirmation and quantification of six neonicotinoid pesticides (dinotefuran, thiamethoxam, clothiandin, imidacloprid, acetamiprid and thiacloprid) in agricultural samples (chestnut, shallot, ginger and tea). Activated carbon and HLB solid-phase extraction cartridges were used for cleaning up the extracts. Analysis is performed by LC–MS/MS operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. Quantification was carried by the internal standard method with D4-labeled imidacloprid. The method showed excellent linearity (R 2 ≥0.9991) and precision (relative standard deviation, RSD≤8.6%) for all compounds. Limits of quantification (LOQs) were 0.01mgkg−1 for chestnut, shallot, ginger sample and 0.02mgkg−1 for tea sample. The average recoveries, measured at three concentrations levels (0.01mgkg−1, 0.02mgkg−1 and 0.1mgkg−1 for chestnut, shallot, ginger sample, 0.02mgkg−1, 0.04mgkg−1 and 0.2mgkg−1 for tea sample), were in the range 82.1–108.5%. The method was satisfactorily validated for the analysis of 150 agricultural samples (chestnut, shallot, ginger and tea). Imidacloprid and acetamiprid were detected at concentration levels ranging from 0.05 to 3.6mgkg−1. [Copyright &y& Elsevier]

Abstract: A fast, simple, low cost, and high throughput method has been developed for the determination of Gibberellin A3 residue in fruit samples (apple, orange, peach, pear and grape). Analysis is performed by LC–MS/MS operated in the multiple reaction monitoring (MRM) mode, acquiring two specific precursor-product ion transitions per target compound. The method has been validated showing good linearity and selectivity. Limits of quantification (LOQs) were 10μgkg−1 for apple, orange, peach, pear and grape samples. The average recoveries, measured at three concentration levels (10, 20 and 200μgkg−1) were in the range 77.8–96.2% for the compound tested with relative standard deviations below 13.7%. The proposed method is rapid, simple and could be utilised for the routine analysis of Gibberellin A3 in fruit samples. [Copyright &y& Elsevier]