The heteropolycyclic compounds containing borole units were theoretically designed. The presence of electron deficient boron atoms results in full electron delocalization and remarkably affects their aromaticity. While molecules 1 and 2a exhibit antiaromaticity for inner rings and non-aromaticity for outer rings, 2b and 2c are completely aromatic.

Several loop-mediated isothermal amplification (LAMP) assays have been developed to detect common causative pathogens of bacterial meningitis (BM). However, no LAMP assay is reported to detect Streptococcus agalactiae and Streptococcus suis, which are also among common pathogens of BM. Moreover, it is laborious and expensive by performing multiple reactions for each sample to detect bacterial pathogen. Thus, we aimed to design and develop a single-tube LAMP assay capable of detecting multiple bacterial species, based on the nucleotide sequences of the 16S rRNA genes of the bacteria. The nucleotide sequences of the 16S rRNA genes of main pathogens involved in BM were aligned to identify conserved regions, which were further used to design broad range specific LAMP assay primers. We successfully designed a set of broad range specific LAMP assay primers for simultaneous detection of four species including Staphylococcus aureus, Streptococcus pneumoniae, S. suis and S. agalactiae. The broad range LAMP assay was highly specific without cross-reactivity with other bacteria including Haemophilus influenzae, Neisseria meningitidis and Escherichia coli. The sensitivity of our LAMP assay was 100-1000 times higher compared with the conventional PCR assay. The bacterial species could be identified after digestion of the LAMP products with restriction endonuclease DdeI and HaeIII.

Following the theme of this special issue, two new compounds, the P-flowers C(16)(PH)(8) and C(16)(PF)(8), are designed by us and subsequently characterized by quantum chemical computations. Their geometries and infrared signatures are analyzed and compared to those of the well-known sulflower C(16)S(8). Their electronic structure and aromaticity are examined using the electron localization function (ELF) and also by the total and partial densities of state (DOS). Both C(16)(PF)(6) and C(16)(PH)(8) molecules exhibit small energy barrier of electron injection (Φ(e) = 0.33 eV for the gold electrode for the former, and Φ(e) = 0.1 eV for the calcium electrode for the latter), remarkably low reorganization energy and high rate of electron hopping. Thus, both theoretically designed P-flower molecules are predicted to be excellent candidates for organic n-type semiconductors.

We performed a theoretical investigation on a series of π-conjugated organic molecules containing naphtho[2,3-b]thiophene and their derivatives using density functional theory calculations. All molecules considered exhibit planar structures and aromaticity. Energy levels of frontier orbitals and reduction and oxidation potentials of these compounds predicted by our solvation model reveal good agreement with available experimental values. The UV absorption spectra point out a clear trend that maximum peaks corresponding HOMO–LUMO transitions are red-shifted: (i) from compounds containing O to those containing Se, (ii) from dimers 1a–3a and 1b–3b to trimers 4a–6a and 4b–6b, and (iii) from parent compounds 1a–6a to perfluorinated derivatives 1b–6b. Parent compounds 1a–6a can be considered as p-type semiconducting materials with low reorganization energies, high transfer integrals, and hole mobility. Perfluorinated compounds 1b–6b are suggested to be very good candidates for ambipolar semiconducting materials. Introduction of fused-ring core molecules considerably improves the charge transport characteristics of the co-oligomers 4a–6a and 4b–6b as compared to those of corresponding molecules 1a–3a and 1b–3b. Accordingly, the former have lower reorganization energies, higher electron transfer integrals, and higher rates of charge hopping.

Organic semiconducting materials play an important role in the fabrication of high performance organic electronic devices. In the present work, we theoretically designed a series of organic semiconductors based on nickel complexes. Their characteristics of charge transport were investigated using DFT computational approaches. Based on the computed results, all compounds designed are found to be excellent candidates for ambipolar organic semiconductors with low reorganization energies for both holes and electrons. The (I-V) characteristics and transmission spectra of materials show that the replacement of benzene rings by thiophene rings results in an increase of their HOMO and LUMO energy levels. HOMOs of compounds containing thiophene end-groups are likely dominant for their conductance, while LUMOs of compounds containing benzene end-groups mainly affect their conductance. The electron distribution in these frontier MOs is identified as the main reason which makes the conductance of the compounds in the first series higher than those in the later series.