两种铜卟啉金属有机框架对小鼠乳腺癌细胞的光动力作用

以5,10,15,20-四（4-吡啶基）卟啉为原料,分别采用分层法与溶剂热法制备了两种铜卟啉金属有机框架材料（MOF1和MOF2）,其结构及形貌大小经UV-Vis, IR, XRD, TEM和SEM表征。采用1,3-二苯基异苯并呋喃（DPBF）考察材料在光照下生成单线态氧（¹O₂）的能力;在细胞水平上,采用MTT法评价了材料对小鼠乳腺癌细胞（4T1）的体外抑制活性;并采用活性氧探针（DCFH-DA）考察其在光照下产生活性氧的能力。结果表明：两种材料均具有过氧化氢催化能力,可有效改善4T1细胞的缺氧状态,且在光动力作用下MOF1对4T1细胞的毒性作用强于MOF2（P<0.001）。      

980-nm all-fiber mode-locked Yb-doped phosphate fiber oscillator based on semiconductor saturable absorber mirror and its amplifier

A 980-nm semiconductor saturable absorber mirror(SESAM) mode-locked Yb-doped phosphate fiber laser is demonstrated by using an all-fiber linear cavity configuration. Two different kinds of cavity lengths are introduced into the oscillator to obtain a robust and stable mode-locked seed source. When the cavity length is chosen to be 6 m, the oscillator generates an average output power of 3.5 m W and a pulse width of 76.27 ps with a repetition rate of 17.08 MHz. As the cavity length is optimized to short, 4.4-m W maximum output power and 61.15-ps pulse width are produced at a repetition rate of 20.96 MHz. The output spectrum is centered at 980 nm with a narrow spectral bandwidth of 0.13 nm. In the experiment, no undesired amplified spontaneous emission(ASE) nor harmful oscillation around 1030 nm is observed. Moreover,through a two-stage all-fiber-integrated amplifier, an output power of 740 m W is generated with a pulse width of 200 ps.