In this work, we report a new type of quantum dot (QD)-based fluorescence resonance energy transfer (FRET) assembly and its utility for sensing Zn2+ in different media. The assembly on the QD scaffold is via first coating of poly(dA) homopolymer/double-stranded DNA, followed by loading of meso-tetra(4-sulfonatophenyl)porphine dihydrochloride (TSPP), both of which are electrostatic, offering the advantages of cost-efficiency and simplicity. More importantly, the biopolymer coating minimizes the interfacial thickness to be ≤2 nm for QD-TSPP FRET, which results in improvements of up to 60-fold for single FRET efficiency and nearly 4-fold for total FRET efficiency of the QD-biopolymer-TSPP assemblies in comparison with silica-coating-based QD-TSPP assemblies. On the basis of Zn2+-chelation-induced spectral modulation, dual-emission QD-poly(dA)-TSPP assemblies are developed as a ratiometric Zn2+ sensor with increased sensitivity and specificity. The sensor either in solution or on a paper substrate displays continuous color changes from yellow to bright green toward Zn2+, exhibiting excellent visualization capability. By utilizing the competitive displacement of Zn2+, the sensor is also demonstrated to have good reversibility. Furthermore, the sensor is successfully used to visualize exogenous Zn2+ in living cells. Together the QD-biopolymer-TSPP assembly provides an inexpensive, sensitive, and reliable sensing platform not only for on-site analytical applications but also for high-resolution cellular imaging.Keywords: biopolymer; electrostatic assembly; porphyrin; quantum dot; resonance energy transfer; sensor; zinc ion;

•π-Extended triptycene-based stationary phase integrated by 2D and 3D units.•High-resolution capability for structural and positional isomers.•Good potential for determination of isomer impurities in real samples.Triptycene-based materials feature favorable physicochemical properties and unique molecular recognition ability that offer good potential as stationary phases for capillary gas chromatography (GC). Herein, we report the investigation of utilizing a π-extended triptycene material (denoted as TQPP) for GC separations. As a result, the TQPP capillary column exhibited high column efficiency of 4030 plates m−1 and high-resolution performance for a wide range of analytes, especially structural and positional isomers. Interestingly, the TQPP stationary phase showed unique shape selectivity for alkanes isomers and preferential retention for analytes with halogen atoms and H-bonding nature mainly through their halogen-bonding and H-bonding interactions. In addition, the TQPP column had good repeatability and reproducibility with the RSD values of 0.02–0.34% for run-to-run, 0.09–0.80% for day-to-day and 1.4–5.2% for column-to-column, respectively, and favorable thermal stability up to 280 °C. This work demonstrates the promising future of triptycene-based materials as a new class of stationary phases for GC separations.Download high-res image (94KB)Download full-size image

This work explored the separation performance of two new dithienyl benzothiadiazole (TBT)-based materials, namely 4,7-di(5-allyl-2-thienyl)benzothiadiazole (TBT-AA) and 4-(5-allyl-2-thienyl)-7-(5-dodecyl-2-thienyl)benzothiadiazole (TBT-AC12), as the stationary phases for capillary gas chromatography (GC). The TBT-AA and TBT-AC12 columns exhibited medium polarity and achieved a column efficiency of 3700 plates per m and 3800 plates per m, respectively, by n-dodecane under 100 °C. They showed high-resolution performance for analytes of different varieties and advantageous resolving capability for positional and structural isomers, such as chloronitrobenzenes, dibromobenzenes, cymenes and hexanes, over the polysiloxane stationary phase with similar polarity. Moreover, the TBT-based stationary phases display different retention behaviours from the conventional phase via diversified molecular interactions covering π–π and π–π EDA, halogen-bonding, H-bonding interactions and van der Waals forces. Also, they exhibited good column repeatability with the relative standard deviation (RSD) values of less than 0.12% for run-to-run, 1.8% for day-to-day and 5.0% for column-to-column, respectively. This work demonstrates the good potential of the TBT-based stationary phases for GC separations.

A new 3D-structured acceptor TP3, in which three perylene diimide (PDI) units are connected together by a triptycene (TPC) core, is synthesized and characterized. Organic solar cells (OSCs) fabricated with a PTB7-Th:TP3 blend film as the active layer have been investigated and the best power conversion efficiency (PCE) of 3.16% is achieved by adding 0.5% DIO. Our studies suggest that the introduction of the TPC core could suppress the strong self-aggregation tendency of the PDI chromophores.

•A phthalocyanine with eight fused thienyl rings was synthesized.•The phthalocyanine showed the Q-band absorption at 774 nm.•The phthalocyanine was used as a donor in bulk heterojunction solar cells.•A power conversion efficiency of 0.60% was achieved in the solar cell device.We report the synthesis and properties of a phthalocyanine derivative with eight fused thienyl rings and eight triisopropylsilylethynyl substituents. The fused thienyl rings were designed to enhance intermolecular interactions among the phthalocyanine molecules in the solid state whereas the triisopropylsilylethynyl substituents were aimed to improve solubility. Compared to the simple octa(2-thienyl) substituted phthalocyanine, a remarkable decrease of solubility and a 67 nm red shift in UV–visible absorption maximum were observed. The fused thienyl compound was used as a donor material in bulk heterojunction solar cells. The power conversion efficiency of 0.60% was achieved under simulated solar illumination.

Asymmetrically substituted phthalocyanines with sulfur-containing substituents for fabrication of self-assembled monolayers were synthesized. Phthalocyanine 7, bearing a disulfide group, was synthesized from phthalocyanine with a hydroxyl group, which was prepared via mixed condensation of the corresponding substituted phthalonitriles. Phthalocyanine 10, bearing an acetyl protected thiol group, was synthesized through the Pd-catalyzed coupling reaction of an iodophthalocyanine. Their self-assembling behavior on gold substrates was further studied by UV–vis spectroscopy.Asymmetrically substituted phthalocyanines with sulfur-containing substituents for fabrication of self-assembled monolayers were synthesized. Their self-assembling behavior on gold substrates was further studied by UV–vis spectroscopy.

•TBTs as new GC stationary phases are presented.•TBTs show excellent separation performance and thermal stability.•TBTs have a great potential as new separation media for wide applications.Dithienyl benzothiadiazole (TBT) derivatives are characteristic of specific molecular structures and excellent thermal stability, offering the great potential for their use as stationary phases for capillary gas chromatography (GC). However, no related publications are available to date. Here we first report the exploration of two TBT derivatives, namely, 4,7-bis(5-dodecylthiophen-2-yl) benzothiadiazole (TBT-C12, a new derivative), and 4,7-di(thiophen-2-yl) benzothiadiazole (TBT), for the purpose. First, TBT-C12 and TBT were synthesized and statically coated onto capillary columns. Both of the as-prepared columns were characterized as nonpolar nature by the determined McReynolds constants. The results showed that both TBT-C12 and TBT columns achieved excellent separations for n-alkanes, esters and polycyclic aromatic hydrocarbons (PAHs), and the TBT-C12 column exhibited better thermal stability (up to 280 °C) than the TBT column. Moreover, a comparative study between the TBT-type columns and a commercial column was also made, suggesting the better selectivity of the TBT-type stationary phases toward n-alkanes and PAHs than that of the commercial one. Additionally, thermodynamic parameters suggested that the retention behaviors of n-alkanes and PAHs on the TBT-C12 column was mainly controlled by entropy change (ΔS). In conclusion, this work demonstrates the excellent chromatographic performance of TBT derivatives as a new type of GC stationary phases and their potential in separation science.

A new 3D-structured acceptor TP3, in which three perylene diimide (PDI) units are connected together by a triptycene (TPC) core, is synthesized and characterized. Organic solar cells (OSCs) fabricated with a PTB7-Th:TP3 blend film as the active layer have been investigated and the best power conversion efficiency (PCE) of 3.16% is achieved by adding 0.5% DIO. Our studies suggest that the introduction of the TPC core could suppress the strong self-aggregation tendency of the PDI chromophores.