摘要
在多壁碳纳米管(MWNTs)表面固定Fe3O4(核)/Au(壳)纳米微粒(GMP),使其具有超顺磁性,包被p24抗体(anti p24),制得检测探针(MWNTs-GMP/anti p24);在磁场作用下将此探针吸附于N,N'-双(2-羟基苯亚甲基)邻苯二胺合铜(CuRb)修饰的碳基丝网印刷电极(SPCE|CuRb)表面,制得了免疫传感电极(SPCE|CuRb/MWNTs-GMP/anti p24)。当此电极在含p24样本中于室温下温育15min后,随p24浓度的增加在电极表面生成的免疫复合物增加,导致CuRb对H2O2的催化还原电流下降。在含5mmol/L H2O2的PBS(pH7.0)中和-300mV下,催化还原电流降低值ΔIo与p24浓度在0.6～160μg/L呈线性关系;检出限为0.32μg/L(3σ)。将其用于实际样品检测,结果与标准EILSA方法一致。由于MWNTs-GMP/anti p24具有超顺磁性,并可以显著提高电极比表面积及anti p24负载量,而CuRb代替易失活的HRP酶,使得该传感器灵敏度和稳定性俱佳,电极表面可更新,可用于艾滋病人血清中p24筛测。
A magnetism controlled and non-enzyme amperometric immunosensor was fabricated for the determination of human immunocleficiency virus p24 （ HIV p24 ） . First,Fe3O4 /Au composite nanoparticles （ GMP） were modified on multiwalled carbon nanotubes （ MWNTs-GMP） . Then,antibody of p24（ anti p24） was coated on it to prepare MWNTs-GMP/anti p24 biomarker. Finally,the marker was absorbed on the surface of N,N＇-Bis （ 2-hydroxy-methylene） -o-phenylenediamine copper （ CuRb） modified screen-printed carbon electrodes （ SPCEs） through external magnetic field in which CuRb can be employed as an electron transfer mediator and catalyst for detection of H2O2. After the immunosensor is incubated with p24 sample at room temperature for 15 min,the electron transfer access of CuRb to H2O2 is partly inhibited,which leads to a linear decrease of the catalytic efficiency to H2O2 at 300 mV in pH 7. 0 PBS. Under optimal conditions,the linear range of p24 is from 0. 6 to 160 μg/L and the detection limit is 0. 32 μg/L at 3 times noise. The immunosensor was employed to determine p24 in acquired immure deficiency syndrome （ AIDs） patients＇ serum samples and the results were consistent to the tradition ELISA method which was suitable for screen determination of trace p24 in serums of AIDs＇ patients.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
2010年第11期1556-1562,共7页
Chinese Journal of Analytical Chemistry
基金
国家自然科学青年基金(No.20805024)
浙江省自然科学基金(Nos.Y20805024
2008C50012)
广东省科技计划项目(No.2008A050200006)
宁波大学王宽诚基金资助项目
