目的检测三磷酸腺苷结合盒转运体A1(ABCA1)蛋白第2跨膜结构域(the second transmembrane domain,TMD2)中关键的抗砷结构域。方法采用重叠区扩增基因拼接法构建三磷酸腺苷结合盒转运体A1基因TMD2的一系列缺失突变体,分别转染至HeLa细胞,...目的检测三磷酸腺苷结合盒转运体A1(ABCA1)蛋白第2跨膜结构域(the second transmembrane domain,TMD2)中关键的抗砷结构域。方法采用重叠区扩增基因拼接法构建三磷酸腺苷结合盒转运体A1基因TMD2的一系列缺失突变体,分别转染至HeLa细胞,激光共聚焦观察其定位,Cell Counting Kit-8检测48 h急性砷中毒后生存率的变化,原子荧光吸收光谱法检测细胞内的总砷含量。结果激光共聚焦证实各突变体的编码蛋白均定位在HeLa细胞的细胞膜上。CCK-8结果显示,转染胞外第4、5环,胞内第4、5环缺失突变体的HeLa细胞IC50分别为33.18、32.84、33.45、34.29μmol.L-1,与转染野生型三磷酸腺苷结合盒转运体A1质粒的HeLa细胞(IC50为33.96μmol.L-1)无显著差异,均高于空载体转染对照组(IC50为19.01μmol.L-1)。转染胞外第6环缺失突变体HeLa细胞的IC50为19.95μmol.L-1,与空载体对照组无显著差异,显著低于野生型三磷酸腺苷结合盒转运体A1质粒转染组。原子荧光分光光度法结果显示,转染胞外第6环缺失三磷酸腺苷结合盒转运体A1的HeLa细胞内砷含量与转染空载体接近,而转染其他突变体的结果与转染野生型三磷酸腺苷结合盒转运体A1的结果基本一致。结论成功构建了5个三磷酸腺苷结合盒转运体A1蛋白第2跨膜结构域的缺失突变体,且其表达的蛋白仍然正确定位于HeLa细胞的细胞膜上。突变体(除胞外第6环外)仍然具有一定的抗砷性,提示三磷酸腺苷结合盒转运体A1胞外第6环可能是关键抗砷结构域。展开更多
2D SnS_2 nanosheets are exfoliated by micromechanical exfoliation technique from SnS_2 single crystals which are synthesized by CVT methods.Monolayer SnS_2 nanosheet has been obtained and the Raman spectrum shows that...2D SnS_2 nanosheets are exfoliated by micromechanical exfoliation technique from SnS_2 single crystals which are synthesized by CVT methods.Monolayer SnS_2 nanosheet has been obtained and the Raman spectrum shows that A_（1g） mode of monolayer SnS_2 shows a slight softening compared with bulk SnS_2 single crystal.The field effect transistors（FETs） based on multilayer SnS_2 nanosheets have been fabricated,of which the electrical and photoelectrical properties have been measured.Under dark condition,with V_（sd） of 1 V,our SnS_2 FET shows n-type behavior.The carrier mobility of the FETs reach 3.51 cm^2V^（-1）s^（-1） and the ‘ON/OFF’ ratio is about 5×10~2.The SnS_2 FET is also illuminated under 532 nm laser with the power of 500 m W/cm^2.The light absorption causes an increment of carrier mobility（from 3.51 cm^2V^（-1）s^（-1） under dark condition to 3.85 cm^2V^（-1）s^（-1） under 532 nm laser illumination with the power of 500 m W/cm^2/ of SnS_2.The responsivity（R） and detectivity of our multilayer device under 500 m W/cm^2532 nm is 2.08 A/W and 6×10~6 J,respectively.All the above properties indicate the potential of SnS_2 nanosheets to be used as FETs and phototransistors.展开更多
2D materials including graphene and TMDs have proven interesting physical properties and promising optoelectronic applications.We reviewed the growth,characterization and optoelectronics based on 2D TMDs and their het...2D materials including graphene and TMDs have proven interesting physical properties and promising optoelectronic applications.We reviewed the growth,characterization and optoelectronics based on 2D TMDs and their heterostructures,and demonstrated their unique and high quality of performances.For example,we observed the large mobility,fast response and high photo-responsivity in Mo S;,WS;and WSe;phototransistors,as well as the novel performances in vd W heterostructures such as the strong interlayer coupling,am-bipolar and rectifying behaviour,and the obvious photovoltaic effect.It is being possible that 2D family materials could play an increasingly important role in the future nano- and opto-electronics,more even than traditional semiconductors such as silicon.展开更多
文摘2D SnS_2 nanosheets are exfoliated by micromechanical exfoliation technique from SnS_2 single crystals which are synthesized by CVT methods.Monolayer SnS_2 nanosheet has been obtained and the Raman spectrum shows that A_（1g） mode of monolayer SnS_2 shows a slight softening compared with bulk SnS_2 single crystal.The field effect transistors（FETs） based on multilayer SnS_2 nanosheets have been fabricated,of which the electrical and photoelectrical properties have been measured.Under dark condition,with V_（sd） of 1 V,our SnS_2 FET shows n-type behavior.The carrier mobility of the FETs reach 3.51 cm^2V^（-1）s^（-1） and the ‘ON/OFF’ ratio is about 5×10~2.The SnS_2 FET is also illuminated under 532 nm laser with the power of 500 m W/cm^2.The light absorption causes an increment of carrier mobility（from 3.51 cm^2V^（-1）s^（-1） under dark condition to 3.85 cm^2V^（-1）s^（-1） under 532 nm laser illumination with the power of 500 m W/cm^2/ of SnS_2.The responsivity（R） and detectivity of our multilayer device under 500 m W/cm^2532 nm is 2.08 A/W and 6×10~6 J,respectively.All the above properties indicate the potential of SnS_2 nanosheets to be used as FETs and phototransistors.
文摘2D materials including graphene and TMDs have proven interesting physical properties and promising optoelectronic applications.We reviewed the growth,characterization and optoelectronics based on 2D TMDs and their heterostructures,and demonstrated their unique and high quality of performances.For example,we observed the large mobility,fast response and high photo-responsivity in Mo S;,WS;and WSe;phototransistors,as well as the novel performances in vd W heterostructures such as the strong interlayer coupling,am-bipolar and rectifying behaviour,and the obvious photovoltaic effect.It is being possible that 2D family materials could play an increasingly important role in the future nano- and opto-electronics,more even than traditional semiconductors such as silicon.
