水凝胶微流控芯片的快速加工及在细胞培养检测中的应用

采用具有紫外光聚合性能的聚乙二醇(PEG)基水凝胶材料, 通过紫外光聚合作用快速加工双层水凝胶微流控芯片, 并验证了其对肿瘤细胞代谢液进行检测的可行性. 与传统微流控芯片材料相比, 该水凝胶芯片材料具有更好的生物相容性及可操控性, 可直接加工成形, 在生物学领域特别是细胞培养过程控制方面具有良好的应用前景. 实验结果表明, 该水凝胶微流控芯片可在微尺度空间有效模拟细胞生长环境, 并实现对细胞连续捕获后的原位培养. 将该芯片与卟啉可视阵列传感器系统结合, 经代谢特征分析可有效区分不同种类肿瘤细胞, 实现芯片细胞培养平台上的细胞代谢指纹快速可视化传感检测.     

Tetragonal Distortion of InN Thin Films by RBS/Channeling

Rutherford backscattering and channeling spectrometry （RBS/C） are used to identify the crystalline quality （Xmin = 4.87%） Of an InN thin film as a function of depth, and make a non-destructive quantitative analysis of the structure, in order to analyze the tetragonal distortion of the InN thin film at the depth determined.     

Integratomics of Human Dermal Fibroblasts Treated with Low Molecular Weight Hyaluronic Acid

Hyaluronic acid (HA) is a glycosaminoglycan very common in commercial products from pharmaceuticals to cosmetics due to its widespread distribution in humans and its diversified physico-chemical proprieties. Despite its extended use and preliminary evidence showing even also opposite activities to the native form, the precise cellular effects of HA at low-molecular-weight (LWM-HA) are currently unclear. The ‘omics sciences currently in development offer a new and combined perspective on the cellular and organismal environment. This work aims to integrate lipidomics analyses to our previous quantitative proteomics one for a multi-omics vision of intra- and extra-cellular impact of different concentrations (0.125, 0.25, and 0.50%) of LMW-HA (20–50 kDa) on normal human dermal fibroblasts by LC-high resolution mass spectrometry (LC-HRMS). Untargeted lipidomics allowed us to identify 903 unique lipids mostly represented by triacylglycerols, ceramides, and phosphatidylcholines. According to proteomics analyses, LMW-HA 0.50% was the most effective concentration also in the lipidome rearrangement especially stimulating the synthesis of ceramides involved in skin hydration and reparation, cell signaling, and energy balance. Finally, integrative analyses showed 25 nodes covering several intra- and extra-cellular functions. The more complete comprehension of intra- and extra-cellular effects of LMW-HA here pointed out will be useful to further exploit its features and improve current formulations even though further studies on lipids biosynthesis and degradation are necessary.     

Laser Ablation Synthesis of Gold Selenides by using a Mass Spectrometer as a Synthesizer: Laser Desorption Ionization Time‐of‐Flight Mass Spectrometry

Methods for the rapid construction of new chemical motifs have the potential to accelerate the development of nanoscience. The synthesis of new chemical entities by laser ablation has been systematically demonstrated by using mixtures of gold and selenium. The compounds generated are detected by time‐of‐flight mass spectrometry and, for selected compounds, the structure is investigated by using density functional theory optimization. In total, 67 new gold selenide clusters have been synthesized, demonstrating an unsuspected richness in gold chemistry. Chemical species generated in the gas phase might inspire new routes for the synthesis of novel compounds in the solid state.     

Molecular determinants for drug-receptor interactions Part 14. X-ray molecular structure and theoretical conformational (MNDO, MM2) studies of the narcotic dualist buprenorphine hydrochloride

The X-ray molecular structure of buprenorphine hydrochloride [(C₂₉H₄₂O₄N)⁺Cl⁻] was determined. The molecule forms colourless tetragonal crystals; the space group is P4₁2₁2₁ with eight molecules per unit cell of dimensions a = 11.507(2) Å and c = 41.952(9) Å. The structure was determined by direct methods and refined by the full-matrix least-squares procedure to R = 0.056 for 2251 observed reflections. The protonated buprenorphine (BPNH⁺) in the solid state adopts the T-shape form typical of benzomorphan compounds; the substituent group at the N atom is in the equatorial configuration and the cyclopropylmethyl side-chain is almost perpendicular to the piperidine ring. Theoretical studies of the conformations and the rotational energetics of BPNH⁺ were performed using both the semiquantitative MNDO and the force field (MM2) methods. The latter method predicted four low energy conformations about the N-C(21) and C(21)-C(22) bonds. Two of these were more significantly populated (59% and 30%). They may easily interconvert through only a single torsional process. The less-populated (30%) conformation was consistent with that adopted in the solid state. The MNDO method predicted different low energy conformations of the N-cyclopropylmethyl moiety. Neither method reproduced the favoured torsional angles adopted by the structurally analogous naltrexone molecule which has the opposite pharmacological profile.     

TEM and photoluminescence characterization of porous-silicon layers from <111>-oriented p + silicon substrates

Summary A first structural investigation, carried out by transmission electron microscopy on porous-silicon samples fromp ⁺, <111>-oriented substrates is presented. The samples, which show intense visible room temperature luminescence, are composed by an interconnected network of crystalline nanostructures. Evidences of the pores propagation along the <100> directions are provided. The optical and morphological characteristics of the investigated samples are found to be much similar to those of samples coming fromp-type, non-degenerate, <100>-oriented substrates rather than those obtained from <100> substrates with comparable resistivity. This striking effect is explained by invoking different etch-limiting mechanisms during pore formation. Their relative weights are proposed to depend on the crystallographic orientation of the silicon specimen subjected to etching. Paper presented at the III INSEL (Incontro Nazionale sul Silicio Emettitore di Luce), Torino, 12–13 October 1995.