基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption ionization-time of flight mass spectrometry,MALDI-TOF MS)是一种可以对多种微生物(包括细菌、酵母和丝状真菌)进行常规鉴定的强有力工具。具有快速、准确、高...基质辅助激光解吸电离飞行时间质谱(matrix-assisted laser desorption ionization-time of flight mass spectrometry,MALDI-TOF MS)是一种可以对多种微生物(包括细菌、酵母和丝状真菌)进行常规鉴定的强有力工具。具有快速、准确、高通量及成本低廉等特点,逐渐被用于丝状真菌感染的实验室诊断中。在丝状真菌的MALDI-TOF MS分析中,从样本制备到获得准确的鉴定结果,每个步骤都决定了医技人员能否及时为临床医生提供准确结果。现就待测样品的制备及MALDI-TOF MS技术对丝状真菌分析(包括鉴定、分型、抗真菌敏感性测试方面)的应用及前景作一系统综述,也将对其一些未来发展进行展望。展开更多
The luminescent liquid crystals (LLCs) are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy ...The luminescent liquid crystals (LLCs) are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy of applying aggregation-induced emission (AIE) phenomenon to the molecular design of LCs towards LLCs. In this report, a calamitic liquid crystal based on tolane with AIE characteristics was successfully synthesized and the chemical structure was characterized by 1H, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) high-resolution mass spectra. The fluorescence behavior was studied by fluorescence spectroscopy and the liquid crystal phase behaviors were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM). The crystal structure was obtained by X-ray diffraction crystallography with P1 space group. Results demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic, smectic C and smectic B phase.展开更多
Protein-polymer hybrids consisting of protein and natural polymers or synthetic polymers exhibit superior properties to un- modified proteins, generating a high demand for these materials in the fields of medicine, bi...Protein-polymer hybrids consisting of protein and natural polymers or synthetic polymers exhibit superior properties to un- modified proteins, generating a high demand for these materials in the fields of medicine, biotechnology, and nanotechnology. Herein, protein-polysaccharide hybrids were fabricated via the formation of an amide bond between bovine serum albumin （BSA） and chitosan （CS） using N-ethyl-N-（3-dimethylaminopropyl） carbodiimide hydrochloride （EDC） as the couple reagent. FTIR spectrum reveals that the carboxyl group of BSA conjugated with the amino group of chitosan backbone. The molecular weight of BSA-CS hybrids was identified by matrix-associated laser desorption ionization time of flight mass spectra （MALDI-TOF MS） and sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE）. The maximum number of chitosan chains binding to each BSA molecule was estimated as 6, and the optimal number was estimated as 2. In addition, the secondary structure and surface property of BSA were dependent upon the number of polymer conjugating on protein. The secondary structure of BSA was not significantly changed, if a few chitosans were coupled with BSA. By further increasing the molar ratio of chitosan to BSA, the secondary structure of BSA was markedly damaged. The surface＇s negative charges of modified BSA also decreased. The result of native polyaerylamide gel electrophoresis （native-PAGE） also demonstrated the changes in surface charges and molecular weight of BSA-CS hybrids.展开更多
基金the National Natural Science Foundation of China (21074073, 21104044)Shenzhen Science and Technology Bureau (ZYC201105130112A, JC201105130384A)
文摘The luminescent liquid crystals (LLCs) are expected to solve the conflicts between the aggregation caused quenching and the requirement of aggregation or self-organization for LCs. Herein, we developed a new strategy of applying aggregation-induced emission (AIE) phenomenon to the molecular design of LCs towards LLCs. In this report, a calamitic liquid crystal based on tolane with AIE characteristics was successfully synthesized and the chemical structure was characterized by 1H, 13C NMR, and matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) high-resolution mass spectra. The fluorescence behavior was studied by fluorescence spectroscopy and the liquid crystal phase behaviors were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM). The crystal structure was obtained by X-ray diffraction crystallography with P1 space group. Results demonstrated that the sample was AIE active and the LC phases sequence during cooling was nematic, smectic C and smectic B phase.
基金supported by the National Natural Science Foundation of China (21164003,20964002)the Gansu Sci & Techn Support Project(1011GKCA017)+2 种基金the Fundamental Res. Funds Univ. Gansu Province(2010-176)Lanzhou Science Technology Bureau (2009-1-14)NWNU-kjcxgc-03-63
文摘Protein-polymer hybrids consisting of protein and natural polymers or synthetic polymers exhibit superior properties to un- modified proteins, generating a high demand for these materials in the fields of medicine, biotechnology, and nanotechnology. Herein, protein-polysaccharide hybrids were fabricated via the formation of an amide bond between bovine serum albumin （BSA） and chitosan （CS） using N-ethyl-N-（3-dimethylaminopropyl） carbodiimide hydrochloride （EDC） as the couple reagent. FTIR spectrum reveals that the carboxyl group of BSA conjugated with the amino group of chitosan backbone. The molecular weight of BSA-CS hybrids was identified by matrix-associated laser desorption ionization time of flight mass spectra （MALDI-TOF MS） and sodium dodecyl sulfate polyacrylamide gel electrophoresis （SDS-PAGE）. The maximum number of chitosan chains binding to each BSA molecule was estimated as 6, and the optimal number was estimated as 2. In addition, the secondary structure and surface property of BSA were dependent upon the number of polymer conjugating on protein. The secondary structure of BSA was not significantly changed, if a few chitosans were coupled with BSA. By further increasing the molar ratio of chitosan to BSA, the secondary structure of BSA was markedly damaged. The surface＇s negative charges of modified BSA also decreased. The result of native polyaerylamide gel electrophoresis （native-PAGE） also demonstrated the changes in surface charges and molecular weight of BSA-CS hybrids.
