A Selenophene Analogue of PCDTBT: Selective Fine-Tuning of LUMO to Lower of the Bandgap for Efficient Polymer Solar Cells

In an attempt to further improve the performance of the PCDTBT-based polymer solar cells (PSCs), we have synthesized a selenophene analogue of PCDTBT, namely, <b>PCDSeBT</b>, in which diselenienylbenzothiadiazole (DSeBT) monomer alternately flanks with a 2,7-carbazole unit. The intrinsic properties of <b>PCDSeBT</b> are not only characterized by UV–vis absorption, cyclic voltammetry (CV), and organic field-effect transistors (OFETs) but also the surface morphology, mobilities of space charge-limited current (SCLC) model, and polymer solar cells (PSCs) in its bulk-heterojunction (BHJ) active layer with [6,6]-phenyl C₇₁-butyric acid methyl ester (PC₇₁BM) are evaluated in detail. It is found that <b>PCDSeBT</b> simultaneously has a low-lying highest occupied molecular orbital (HOMO) energy level at −5.4 eV and a low bandgap of 1.70 eV as required by the ideal polymers for BHJ PSCs. The high current of 11.7 mA/cm² is obtained for <b>PCDSeBT</b>-based PSCs, to our knowledge, which is among the highest short-circuit current density (<i>J</i>_<i>SC</i>) values obtained from a BHJ device consisting of PCDTBT derivatives and [6,6]-phenyl C₆₁-butyric acid methyl ester (PCBM). The high <i>J</i>_<i>SC</i> value, along with a moderate fill factor (<i>FF</i>) of 45% and a high open-circuit voltage (<i>V</i>_<i>OC</i>) of 0.79 V, yields a power conversion efficiency (PCE) of 4.12%, which is about 37% increase in PCE from a PCDTBT-based reference device. On the basis of our results, one can be concluded that the DSeBT placement for construction of donor (D)-acceptor (A) polymers is an easy and effective way to realize both the higher <i>J</i>_<i>SC</i> and <i>V</i>_<i>OC</i> values in PSCs, as a consequence of the selective lower-lying lowest unoccupied molecular orbital (LUMO) with the HOMO being almost unchanged, together with the effective broadening on the absorption band

<i>Mater^tm/tm</i> oocytes display elevated levels of lipid droplets.

<p>(<b>A</b>) Low magnification (x1,700) TEM images of <i>Mater^+/+</i> and <i>Mater^tm/tm</i> GV-stage oocytes. Oocytes were prepared for TEM as above. White arrows point to LDs. (<b>B</b>) Confocal images of GV-stage live <i>Mater^+/+</i> and <i>Mater^tm/tm</i> oocytes following Nile red staining. DIC images show morphology of LDs in oocytes. Close up images (Right panel) highlight LD aggregates. Arrows indicate LDs. (<b>C</b>) Quantitation of the volume fractions of CPLs, LDs, mitochondria, and ER in <i>Mater^+/+</i> and <i>Mater^tm/tm</i> GV-stage oocytes. Mean ± SEM is indicated. <i>P</i> value is <0.004 for CPLs, <0.04 for LD, >0.05 for mitochondria, and ER.</p

PADI6 Triton X-100 solubility is increased in <i>Mater^tm/tm</i> GV-stage oocytes.

<p>(<b>A</b>) Confocal analysis shows <i>Mater^+/+</i> and <i>Mater^tm/tm</i> GV-stage oocytes prior to, and following, extraction with 0.1% Triton X-100. Oocytes were incubated with PADI6 antibodies (red). (<b>B</b>) Western blotting shows expression of MATER and PADI6 protein in <i>Mater^+/+</i> and <i>Mater^tm/tm</i> GV-stage oocytes prior to, and following, 0.1% Triton X-100 extraction. Isolated oocytes were either extracted or not extracted with Triton, and then evaluated by Western blotting using either anti-MATER, anti-PADI6, or anti-β actin antibodies.</p

Co-localization of MATER and PADI6 in non-extracted and Triton X-100 extracted GV oocytes and early embryos.

<p>(<b>A</b>) Confocal microscopic images show non-extracted GV-stage oocytes, 2-cell, and 4-cell embryos after fixation, permeabilization and incubation with anti-MATER (green) and anti-PADI6 (red) antibodies. (<b>B</b>) GV oocytes extracted with 0.1% Triton X-100 and stained with MATER (green) and PADI6 (red) antibodies. Merged images highlight MATER and PADI6 co-localization. Scatter plot indicates a degree of co-localization of MATER and PADI6. Region A shows pixels with high MATER (green) intensities, region B shows pixels with high PADI6 (red) intensities, and region C shows pixels with both high MATER (green) and PADI6 (red) intensities. Mander's overlap coefficient: 0.97, Pearson's correlation coefficient: 0.7. (<b>C</b>) CD1 mouse oocyte lysates were chromatographed by FPLC. Eluted fractions (1 ml) were analysed by immunoblotting with antibodies to PADI6 and MATER. Densitometry was used to generate a graph and the values in fraction 11 were set at a relative intensity of 100%. Elution of each protein standard is indicated by arrow.</p

Accuracy of the Fluorescence-Activated Cell Sorting Assay for the Aquaporin-4 Antibody (AQP4-Ab): Comparison with the Commercial AQP4-Ab Assay Kit

<div><p>Background</p><p>The aquaporin-4 antibody (AQP4-Ab) is a disease-specific autoantibody to neuromyelitis optica (NMO). We aimed to evaluate the accuracy of the FACS assay in detecting the AQP4-Ab compared with the commercial cell-based assay (C-CBA) kit.</p><p>Methods</p><p>Human embryonic kidney-293 cells were transfected with human aquaporin-4 (M23) cDNA. The optimal cut off values of FACS assay was tested using 1123 serum samples from patients with clinically definite NMO, those at high risk for NMO, patients with multiple sclerosis, patients with other idiopathic inflammatory demyelinating diseases, and negative controls. The accuracy of FACS assay and C-CBA were compared in consecutive 225 samples that were collected between January 2014 and June 2014.</p><p>Results</p><p>With a cut-off value of MFIi of 3.5 and MFIr of 2.0, the receiver operating characteristic curve for the FACS assay showed an area under the curve of 0.876. Among 225 consecutive sera, the FACS assay and C-CBA had a sensitivity of 77.3% and 69.7%, respectively, in differentiating the sera of definite NMO patients from sera of controls without IDD or of MS. Both assay had a good specificity of 100% in it. The overall positivity of the C-CBA among FACS-positive sera was 81.5%; moreover, its positivity was low as 50% among FACS-positive sera with relatively low MFIis.</p><p>Conclusions</p><p>Both the FACS assay and C-CBA are sensitive and highly specific assays in detecting AQP4-Ab. However, in some sera with relatively low antibody titer, FACS-assay can be a more sensitive assay option. In real practice, complementary use of FACS assay and C-CBA will benefit the diagnosis of NMO patients, because the former can be more sensitive among low titer sera and the latter are easier to use therefore can be widely used.</p></div

Results of the ROC analysis.

<p>The ROC analysis showed that the MFIis for the FACS revealed an area under the curve of 0.876 when detecting sera from patients with definite NMO. Abbreviations: FACS = fluorescence-activated cell sorting, MFIi = mean fluorescence intensity index, NMO = neuromyelitis optica, ROC = receiver operating characteristic.</p

Examples of the FACS data.

<p>The FACS data for healthy control, positive control with diverse dilution concentrations, and positive test results are shown.</p

Results of the commercial cell-based assay kit according to the FACS assay grouped by mean fluorescence intensity index titer.

<p>Results of the commercial cell-based assay kit according to the FACS assay grouped by mean fluorescence intensity index titer.</p

Comparison of the FACS assay with the commercial cell-based assay kit in diverse disease group.

<p>Comparison of the FACS assay with the commercial cell-based assay kit in diverse disease group.</p