Optofluidic detection for cellular phenotyping

Quantitative analysis of the output of processes and molecular interactions within a single cell is highly critical to the advancement of accurate disease screening and personalized medicine. Optical detection is one of the most broadly adapted measurement methods in biological and clinical assays and serves cellular phenotyping. Recently, microfluidics has obtained increasing attention due to several advantages, such as small sample and reagent volumes, very high throughput, and accurate flow control in the spatial and temporal domains. Optofluidics, which is the attempt to integrate optics with microfluidics, shows great promise to enable on-chip phenotypic measurements with high precision, sensitivity, specificity, and simplicity. This paper reviews the most recent developments of optofluidic technologies for cellular phenotyping optical detection.     

Metal complexes of 2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrin: M(2-NCH2C6H5NCTPP) (M = Ni, Pd) and Mn(2-NCH2C6H5NCTPP)Br (NCTPP = N-confused 5,10,15,20-tetraphenyl porphyrinate)

The crystal structures of (2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″) nickel(II) methylene chloride solvate [Ni(2-NCH₂C₆H₅NCTPP); 4], (2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″) palladium(II) [Pd(2-NCH₂C₆H₅NCTPP); 5] and bromo(2-aza-2-benzyl-5,10,15,20-tetraphenyl-21-carbaporphyrinato-N,N′,N″) manganese(III) toluene solvate [Mn(2-NCH₂C₆H₅NCTPP)Br·C₆H₅CH₃; 3·C₆H₅CH₃] have been established. The coordination sphere around the Ni²⁺ ion in 4 (or Pd²⁺ ion in 5) is distorted square planar (DSP), whereas for Mn³⁺ in 3·C₆H₅CH₃, it is a square-based pyramid with the Br atom lying in the axial site. The g value of 11.34, measured from parallel polarization of the X-band EPR spectra at 4 K, is consistent with a high spin mononuclear manganese(III) centre (S = 2) in 3. The magnitude of the axial (D) zero-field splitting (ZFS) for the mononuclear Mn(III) centre in 3 was determined approximately to be 1.4 cm⁻¹ by paramagnetic susceptibility measurements and conventional EPR spectroscopy.     

Very accurate potential energy curve of the He2+ ion

A very accurate ground-state potential energy curve (PEC) of the He(2)(+) molecule is calculated with 1200 explicitly correlated Gaussian functions with shifted centers in the range between 0.9 and 100 a(0). The calculations include the adiabatic corrections determined for the (3)He(4)He(+), (3)He(2)(+), and (4)He(2)(+) isotopologues. The absolute accuracy of the PEC is better than 0.05 cm(-1) and that of the adiabatic corrections is around 0.01 cm(-1). The depths of the PECs augmented with the adiabatic corrections for the three isotopologues are: 19 956.708 cm(-1) for (4)He(2)(+), 19 957.054 cm(-1) for (3)He(4)He(+), and 19 957.401 cm(-1) for (3)He(2)(+). The rovibrational energies are also determined. For (3)He(4)He(+) the computed rovibrational transitions corresponding to the ν = 1-0 band differ from the experiment by less than 0.005 cm(-1). For the rovibrational transitions corresponding to the ν = 23-22 band the difference is around 0.012 cm(-1). Presently, this represents the best agreement between theory and experiment for He(2)(+).     

A rapid and simple HPLC-UV method for the determination of inhibition characteristics of farnesyl transferase inhibitors

Ras proteins play an important role in the development of cancer. Farnesyl transferase inhibitors (FTIs) block the first obligatory post-translational step for activation, prenylation, of Ras proteins. To find new potent FTIs, rapid enzyme activity assays are required to reduce FTI development time. Most assays to date are based on radioactive labelled substrates. We developed a new, in vitro, farnesyl transferase assay based on gradient chromatography coupled to UV detection. Unfarnesylated and farnesylated H-Ras proteins were resolved on a C18 wide-pore HPLC column and their concentrations were determined with use of a calibration curve of unfarnesylated H-Ras. The assay was used to investigate inhibition characteristics of FTIs. The IC50 values of the FTIs L778,123 and SCH66336 were 4.2 nm and 78 microm, respectively. This assay could support the screening and development of FTIs to obtain rapid insights into their inhibitory properties.     

Stable superhydrophobic polybenzoxazine surfaces over a wide pH range

In this study, we report on a simple two-step casting process designed to create a stable superhydrophobic surface. This method possesses the advantages of being both simple and inexpensive as well as utilizing non-fluorine-containing compounds. Most interestingly, we found that the as-prepared surface possesses superhydrophobic properties not only for pure water but also for corrosive water under both acidic and basic conditions. Furthermore, the superhydrophobic polybenzoxazine surfaces had excellent environmental stability with regard to both heating and organic solvent treatment in terms of the contact angle to water.     

Photooxidation of olefins under oxygen in platinum(II) complex-loaded mesoporous molecular sieves

Cyclometalated platinum(II) complex has been successfully incorporated into the (3-aminopropyl) triethoxysilane-modified channels of ordered mesoporous silica SBA-15 that has large pore hexagonal channels. Studies on the (1)O(2) generation conclusively demonstrates that the olefins in the nano-channels of SBA-15 can be enriched 8 times higher than those in the homogeneous solution as the diffusion quantum yield of singlet oxygen ((1)O(2)) is assumed to be unit. The platinum(II) complex loaded in the channel of SBA-15 is stable, and the photosensitized oxidation occurs efficiently. No obvious degradation and leaching of photosensitizers is observed even after 10 runs. Only a simple filtration is needed for the recycled use of the expensive noble metal catalysts. This versatile system is a good example of photochemical reactions occurring in the mesoporous silica molecular sieve. SBA-15 not only provides a support for the photosensitizer, but also acts as a nano-reactor to facilitate the photooxidation.     

First fluorescent sensor for fluoride based on 2-ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded AADD supramolecular assembly

A simple, highly selective, neutral, fluorescent sensor for fluoride anions is reported. It is based on 2-ureido-4[1H]-pyrimidinone quadruple hydrogen-bonded AADD supramolecular assembly, and its assembling and disassembling processes are also able to respond to external stimuli reversibly.     

Numerical Solutions of Matrix Differential Models Using Higher-Order Matrix Splines

This paper deals with the construction of approximate solution of first-order matrix linear differential equations using higher-order matrix splines. An estimation of the approximation error, an algorithm for its implementation and some illustrative examples are included.     

Validation of Material Models in Grain Scale Simulation based on EBSD Experimental Data

A crystal plasticity model and a homogenization method are used to analyze the local and global mechanical behavior of a ferritic stainless steel. In the first step the material constants are determined based on tensile tests and used to simulate the local deformation behavior on the grain scale in the second step. For that 2D EBSD data are discretized by finite elements. The computed local grain reorientations of three different BCC slip systems are compared to experimental data at the state of 20% elongation. (© 2011 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)     

量子点人工光合成化学转换研究进展

利用半导体量子点为光催化剂通过人工光合成的方式把H2O或CO2转化为H2或CO从而获得氢气或其他太阳能燃料,被认为是解决能源和环境危机的有效途径.量子点由于其独特的光物理和光化学性质(如优异的吸光能力、可调的能带结构、多激子生成、表面丰富的活性位点等)在人工光合成化学转换领域受到了广泛的关注.本文总结了近年来作者团队在...