高效液相色谱同时测定饮料中的苯甲酸

文献名： Structural, morphological and optical properties of Bi NPs obtained by laser ablation and their selective detection of L-cysteine 作者： Ramon Gabriel Teixeira Rosaa, Celso de Araujo Duartea , Wido Herwig Schreinera, Ney Pereira Mattoso Filhoa, Arandi Ginane Bezerra Jr.b, Andersson Barisonc, Fernanda Maria Marins Ocamposc a Departamento de Física, Universidade Federal do Paraná Centro Politécnico, CP 19044, 81531-990 Curitiba (PR), Brazil b Departamento Acadêmico de Física, Universidade Tecnológica Federal do Paraná, 80230-901 Curitiba (PR), Brazil c Departamento de Química, Universidade Federal do Paraná Centro Politécnico, CP 19081, 81531-990 Curitiba (PR), Brazil 摘要：In the present work we show the results of the investigation of the properties of bismuth nanoparticles (NPs) obtained by the laser ablation in water. The samples were characterized by various techniques: UV/vis spectroscopy, dynamic light scattering, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, nuclear magnetic resonance and zeta potential. The NPs were metallic and surface oxidated, exhibiting absorption peak at 257 nm due to the surface plasmon resonance. The interaction between the NPs and various amino acids was studied and revealed a selective sensibility to cysteine on a range of concentration from 80 to 720 μM, which we attribute to a dimerization of cysteine to cystine probably complexed to the nanoparticle surface by electrostatic interactions, leading to the modification of the NP absorption spectrum. 关键词：Bismuth; Nanoparticles; Laser ablation; Cysteine

市面上有众多的新冠病毒qPCR检测试剂盒，本应用方案采用韩国Seegene公司的AllplexTM 2019-nCoV检测试剂盒在耶拿荧光定量PCR仪 qTOWER³G上进行样品检测，获得符合预期的结果。

肿瘤特异性抗体功能分析包含很多方面： T细胞功能活化及增殖、细胞因子分析、抗体依赖的细胞介导的细胞毒性作用（antibody-dependent cell-mediated cytotoxicity; ADCC）、抗体介导的补体依赖的细胞毒性（complement dependent cytotoxicity; CDC）、巨噬细胞抗体依赖性的细胞吞噬作用（Antibody-Dependent Cellular Phagocytosis; ADCP）等。

超纯水机在后期使用中会因各种因素导致设备性能下降，所以为了确保延长设备的使用寿命，日常使用时就应该注意设备的维护和保养，那么导致超纯水机性能下降的因素有哪些呢?