Molecularly Imprinted Silica Nanospheres Embedded CdSe Quantum Dots for Highly Selective and Sensitive Optosensing of Pyrethroids

This paper reports the molecularly imprinted polymer (MIP)-based fluorescence nanosensor which is developed by anchoring the MIP layer on the surface of silica nanospheres embedded CdSe quantum dots (QDs) via a surface molecular imprinting process. The molecularly imprinted silica nanospheres (CdSe@SiO2@MIP) were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), IR spectroscopy, and so forth, which demonstrated the formation of uniform core−shell lambda-cyhalothrin(LC)-imprinted silica nanospheres. The synthesized CdSe@SiO2@MIP shows higher photostability, and allows a highly selective and sensitive determination of LC via FL intensity decreasing when removal of the original templates. The CdSe@SiO2@MIP was applied to detect trace LC in water without the interference of other pyrethroids and ions. Under optimal conditions, the relative FL intensity of CdSe@SiO2@MIP decreased linearly with the increasing LC in the concentration in the range of 0.1−1000 μM with a detection limit (3σ) of 3.6 μg·L−1. It is found that LC can quench the luminescence of CdSe@SiO2@MIP in a concentration-dependent manner that is best described by a Stern−Volmer-type equation. The possible mechanism is discussed

Iodide-Catalyzed Synthesis of <i>N</i>‑Nitrosamines via C–N Cleavage of Nitromethane

An iodide-catalyzed process to synthesize <i>N</i>-nitrosamines has been developed using TBHP as the oxidant. The mild catalytic system succeeded in cleaving the carbon–nitrogen bond in nitromethane. This methodology uses commercially available, inexpensive catalysts and oxidants and has a wide substrate scope and operational simplicity

Additional file 1 of The efficacy of computer-assisted cognitive behavioral therapy (cCBT) on psychobiological responses and perioperative outcomes in patients undergoing functional endoscopic sinus surgery: a randomized controlled trial

Additional file 1: Supplementary Table 1. State Trait Anxiety Scale (STAI). Supplementary Table 2. Patients Health Questionnaire-9 (PHQ-9). Supplementary Table 3. Athens Insomnia Scale (AIS). Supplementary Table 4. Satisfaction Survey Questionnaire

A New Strategy for the Construction of α‑Amino Acid Esters via Decarboxylation

A new α-amino acid esters formation reaction has been developed via decarboxylation. The methodology is distinguished by its practical novelty in terms of the readily accessible starting materials, environmentally benign reaction conditions and waste streams, and wide substrate scope

Dinuclear Cobalt Complex-Catalyzed Stereodivergent Semireduction of Alkynes: Switchable Selectivities Controlled by H₂O

Catalytic semireduction of internal alkynes to alkenes is very important for organic synthesis. Although great success has been achieved in this area, switchable Z/E stereoselectivity based on a single catalyst for the semireduction of internal alkynes is a longstanding challenge due to the multi-chemo- and stereoselectivity, especially based on less-expensive earth-abundant metals. Herein, we describe a switchable semireduction of alkynes to (Z)- or (E)-alkenes catalyzed by a dinuclear cobalt complex supported by a macrocyclic bis pyridyl diimine (PDI) ligand. It was found that cis-reduction of the alkyne occurs first and the Z–E alkene stereoisomerization process is formally controlled by the amount of H2O, since the concentration of H2O may influence the catalytic activity of the catalyst for isomerization. Therefore, this protocol provides a facile way to switch to either the (Z)- or (E)-olefin isomer in a single transformation by adjusting the amount of water

Supplemental Material - Development and characterization of kapok/waste silk nonwoven as a multifunctional bio-based material for textile applications

Supplemental Material for Development and characterization of kapok/waste silk nonwoven as a multifunctional bio-based material for textile applications by Hongchang Wang, Liyao Cao, Hang Yuan, Yuling Li, Run Wen and guangbiao Xu in Journal of Industrial Textiles.</p

Additional file 1: of Composition and predictive functional analysis of bacterial communities inhabiting Chinese Cordyceps insight into conserved core microbiome

Figure S1. Rarefaction curves of bacterial community inhabiting Chinese Cordyceps collected from five areas. Figure S1 (A), (B) and (C) were the OTU numbers related with the sequence number in sample of fruiting body, mycoderm and microhabitat soil, respectively. Figure S1 (D), (E) and (F) were the Shannon diversity index related with the sequence number in sample of fruiting body, mycoderm and microhabitat soil, respectively. Samples name were the same with described in Fig. 1 (TIF 413 kb

Powerful Steroid-Based Chiral Selector for High-Throughput Enantiomeric Separation of α‑Amino Acids Utilizing Ion Mobility–Mass Spectrometry

Stereospecific recognition of amino acids (AAs) plays a crucial role in chiral biomarker-based diagnosis and prognosis. Separation of AA enantiomers is a long and tedious task due to the requirement of AA derivatization prior to the chromatographic or electrophoretic steps which are also time-consuming. Here, a mass-tagged chiral selector named [d0]/[d5]-estradiol-3-benzoate-17β-chloroformate ([d0]/[d5]-17β-EBC) with high reactivity and good enantiomeric resolution in regard to AAs was developed. After a quick and easy chemical derivatization step of AAs using 17β-EBC as the single chiral selector before ion mobility–mass spectrometry analysis, good enantiomer separation was achieved for 19 chiral proteinogenic AAs in a single analytical run (∼2 s). A linear calibration curve of enantiomeric excess was also established using [d0]/[d5]-17β-EBC. It was demonstrated to be capable of determining enantiomeric ratios down to 0.5% in the nanomolar range. 17β-EBC was successfully applied to investigate the absolute configuration of AAs among peptide drugs and detect trace levels of d-AAs in complex biological samples. These results indicated that [d0]/[d5]-17β-EBC may contribute to entail a valuable step forward in peptide drug quality control and discovering chiral disease biomarkers

Ag Nanoparticles-Decorated PVDF Nanofiber/Net Membranes with Enhanced Filtration and Antibacterial Efficiency for Personal Protective Equipment

Medical protective masks with both high antibacterial activity and filtration efficiency have gained wide interest due to sporadic respiratory disease outbreaks. Previous studies have focused on improving a single function (antibacterial activity or filtration) of the mask performance. Herein, we developed silver nanoparticles-decorated PVDF membranes (AgNPs/PVDF) with both high antibacterial activity and filtration efficiency. Our results show that AgNPs/PVDF membranes have antibacterial efficiency of 99.98% and 99.86% against E. coliand S. aureus, respectively. The bacterial filtration efficiency is higher than 95%. PM0.26 filtration efficiency can be maintained above 95% after continuous filtration for 144 min. Adding AgNPs also promotes distinct hierarchical structure formation, which could improveme the filtration efficiency. This study provides a new methodology to fabricate antibacterial membranes doped with metal nanoparticles with promising applications in personal protective equipment development

pH and reduction dual-responsive micelles based on novel polyurethanes with detachable poly(2-ethyl-2-oxazoline) shell for controlled release of doxorubicin

We describe a biodegradable amphiphilic polyurethane (PU) with disulfide bonds in the main chain [PEtOz-b-PU(SS)-b-PEtOz]. This multi-block PU was synthesized using poly (ε-caprolactone) diol (PCL-SS-PCL) and poly (2-ethyl-2-oxazoline) (PEtOz-OH) as soft segments, and bis (2-isocyanatoethyl) disulfide as the hard segment. Acid-sensitive PEtOz-OH was used as a hydrophilic segment for pH sensitivity. And reduction sensitivity was induced via disulfide bonds incorporated into the hydrophobic poly (ε-caprolactone) segment of the amphiphilic PUs. The system can self-assemble to form micelles responsive to pH and reducing conditions. The properties of the micelle were studied with dynamic light scattering and scanning electron microscopy. Doxorubicin (DOX) was chosen as a model drug. The in vitro release studies showed that PEtOz-b-PU(SS)-b-PEtOz micelle could degrade more rapidly and completely in a reductive and acidic environment [10 mM dl-Dithiothreitol, pH 5.0]. The methyl tetrazolium (MTT) assay and fluorescent microscopy confirmed the cytotoxicity of the DOX-loaded micelles. This work provides a promising dual-responsive drug carrier based on amphiphilic PU to achieve efficient drug delivery.</p