在高序热解石墨（ＨＯＰＧ）电极上，采用微分脉冲伏安法（ＤＰＶ）和电化学原子力显微镜法（ＥＣＡＦＭ）探究小牛胸腺ＤＮＡ（ＣＴＤＮＡ）在电极表面的吸附．实验发现，控制电位下预极化对双链ＤＮＡ在ＨＯＰＧ电极上的吸附有很大的影响，而对单链ＤＮＡ影响不大．实验表明，在ＨＯＰＧ电极上ＥＣＡＦＭ是ＤＮＡ研究领域十分有用的技术，根据ＡＦＭ图象，结合文献上的ＤＮＡ吸附模型提出了ＣＴＤＮＡ在ＨＯＰＧ电极表面ＤＮＡ吸附的模型．本文还首次采用现场紫外可见反射光谱研究ＤＮＡ的电化学行为，发现对研究ＤＮＡ的吸附该技术具有比伏安法更高的灵敏度
It is shown that calf thymus DNA(CT DNA) can be adsorbed at highly
ordered pyrolytic graphite(HOPG) electrode and detected by differential pulse voltammetry(DPV)
and electrochemical atomic force microscopy(ECAFM). It is found that controlled potential
pre-polarization influences largely the adsorption of dsDNA while it has little influence on
ssDNA. It is demonstrated that ECAFM is useful to exploit adsorption of DNA at HOPGE. The
pattern of adsorption of DNA at HOPG electrode that fits best with the experimental data is
proposed. The results aslo shows that UV/Vis reflection spectroscopy, which has not been used
in studying electrochemical behavior of DNA, is more sensitive than voltammetry in the
investigation of DNA adsorption.
1BrabecV，DryhurstG．Electrochemicalbehaviourofnaturalandbiosyntheticpolynucleotidesatthepyrolyticgraphiteelectrode：Anewprobeforstudiesofpolynucleotidestructureandreactions．J．Electroanal．Chem．，1978，89：161；BrabecV，Electrochemicaloxidationofpolyadenylicacidatgraphiteelectrodes．J．Electroanal．Chem．，1978，91：2192WuJTetal．ElectrochemicalbehavioursofDNAatmercuryfilmelectrode．Bioelectrochem．Bioenerg．1997，44：1513YaoTetal．Theanodicvoltammetryofdeoxyribonucleicacidataglassycarbonelectorde．Bul．Chem．Soc．Japan，1978，51：12354BrabecV，KoudelkaJ．314＿electrochemicaloxidationofnucleicacidsandproteinsatgraphiteelectrode：Qualitiveaspects．Bioelectrochem．Bioenerg．，1980，7：69；BrabecV，KoudelkaJ，394＿Oxidationofdeoxyribonucleicacidatcarbonelectrodes：Theefectofthequalityofthedeoxyribonucleicacidsample．Bioelectrochem．Bioenerg．，1980，7：7935PangDWetal．ModificationofglassycarbonandgoldelectrodeswithDNA．J．Electroanal．Chem．，1996，403：1836BrabecV．133＿nucleicacidanalysisbyvoltammetryatcarbonelectrodes．Bioelectrochem．Bioenerg．，1981，8：4377BretCMAetal．OntheadsorptionandelectrochemicaloxidationofDNAatglasycarbonelectrodes．J．Electroanal．Chem．，1994，366：2258PalecekEetal．Biopolymer＿modifiedelectrodesinthevoltammetricdeterminationofnucleicacidsandproteinsatthesubmicrogramlevel．Anal．ChimicaActa，1993，273：1759LuoJetal．Insituelectronicspectroscopictechniquesforinterfacialelectrochemistry．Chem．Res．ChineseUniv．，1996，12：27010GyalRN，DryhurstG．Redoxchemistryofguanineand8＿oxyguanineandacomparisonoftheperoxidase＿catalyzedandelectrochemicaloxidationof8＿oxyguanine．J．Electroanal．Chem．，1982，135：7511EngelA．Biologicalapplicationsofscanningprobemicroscopes．Annu．Rev．Biophys．Chem．，1991，20：7912BloomfieldVA，ArscotPG．NucleicAcidsandMolecularBiology．EcksteinF，LileyDMJ（eds．），Springer，Berlin，Heidelberg，1991，5：3913MalfoyB，ReynaudJA．ElectrochemicalInvestigationofNucleicAcidBehaviourPartI．NativeCalfThymusDNA．J．Electroanal．Chem．，1976，67：
