Electrochemical Study on the Interaction of D NA with Several Surfactants

Transcript

1 ACTA CHIMICA SINICA Vol No DNA Ξ Ξ ( ) - (MB) DNA DNA DNA DNA MB MB DNA DNA ( ) DNA MB DNA Electrochemical Study on the Interaction of D NA with Several Surfactants ZHAO Fa2Qiong ZENG Bai2Zhao PANG Dai2Wen Ξ ( College of Chemical and Molecular Science Wuhan University Wuhan ) Abstract The interaction of DNA with several surfactants was investigated by cyclic voltammetry UV2vis spectrum and ac impendance using MB as the redox probe It was found that all anionic cationic and non2ionic surfactants can bind to DNA immobilized on the electrode surface changing the surface state of DNA thus affects the electrochemical behavior of the probe The interaction between DNA and anionic surfactants is attributed to electrostatic repulsion and hydrophobic binding which makes the peak current of MB decrease Non2ionic surfactants bind to DNA weakly but they can partly change the conformation of surface DNA because they changed the solution properties While cationic surfactants bind to DNA via hydrophobic interaction and electrostatic attraction This interaction is influenced by the length of the hydrophobic carbon chain and the size of the polar headgroup of cationic surfactants Among them cetyltrimethylammonium bromide and dodecyltrimethylammonium chloride can improve the electrochemical response of the probe in certain concentration range while cetylpyridinium bromide and octadecyltrimethylammonium bromide depress the probe s response Keywords DNA surfactant methylene blue gold electrode [7 Bard 8] DNA [1 3] [9 10] [4 6] [11] DNA DNA DNA [12 15] DNA Ξ E2mail : edu cn Received July ; revised September ; accepted September (Nos )

2 No 1 : DNA 23 DNA ) 510 mv Hz CHI 617A ( ) 273A 2 1 MB 5210 ( EG & G PAR ) 1339 ( ) 5 mmol/ L MB : ( DNA ( 1a) ( E pc ) DNA/ Au) HO2( CH 2 ) 6 2S2S2( CH 2 ) 6 2O ( PO) 3 TGTACA2 GTCATCGGG23 ( HS2ssDNA ) 5 2CCCGATGACTGTACA23 ( ss2 DNA) ( ) ; DNA SDS MB i p 165 g/ ml HS2ssDNA TE (10 mmol/ L ph 810 Tris2HCl + 1 mmol/ L EDTA) 165 g/ ml ssdna TE ( ssdna i pc ) 2 mol/ L NaCl NaCl 015 mol/ MB L 38 2 h MB 2 h 015 mol/ L NaCl 21 mol/ L HS2 MB dsdna (MB ) (DTAC ) (CTAB 98 % BDH ) MB (CPB > 98 % Fluka ) MB (OPB ) ( SDS ) Triton X2100 (Rohm2Haas ) Tween280 ( MB (MB red ) ) Triton X2100 Tween MB i pa MB SDS 1 2 DNA/ Au MB 0105 m Al 2 O 3 MB i pc SDS 015 mol/ L H 2 SO 4 [16] (01047 cm 2 ) 3 L 313 mol/ L HS2ssDNA ( 10 pmol) ( 015 mol/ L NaCl) 2 L 21 mol/ L HS2dsDNA ( 40 pmol) 315 h HS2ssDNA ( ssdna2s/ Au) HS2dsDNA (dsdna2 S/ Au) mmol/ L ph min 5 mol/ L MB V ( E pa ) V (CTAB DTAC CPB OPB) MB i pa i pc E pa E pc E pc Triton X2100 Tween280 MB 5 10 min 1 MB DNA 015 mmol/ L Figure 1 CVs of 10 mol/ L MB at a bare gold electrode (a) and K 3 Fe ( CN) 6 / 015 mmol/ L K 4 Fe ( CN) mol/ L MB at ssdna2s/ Au (b) and dsdna2s/ Au (c) mol/ L (ph 619) Electrolyte : 5 mmol/ L phosphate saline buffer (ph 619) Scan rate : V (Fe (CN) / Fe (CN) mv/ s ; scan direction : negative first

3 24 Vol MBred i pa SDS i pa 1 E pa E pc E p E p MB - SDS MB 660 nm OPB Tween280 MB MB [17 19] MB [18 19] 2 MB DNA Figure 2 Dependence of peak current of MB on the scan rate MB 2 2 DNA MB (a) dsdna2s/ Au and (b) ssdna2s/ Au 5 mmol/ L phosphate buffer (ph 619) + 5 mol/ L MB other conditions are as in Figure 1 MB MB ssdna 1 b c MB ssdna2s/ Au dsdna2s/ MB dsdna Au MB [6] MB dsdna ssdna2s/ Au i pa i pc 146 % 65 % [20 21] dsdna2s/ Au MB dsdna2s/ Au 223 % 124 % MB DNA MB MB 2 MB MB dsdna i pa i pc MB DNA/ Au 1 ( 2 3 ) ssdna dsdna MB ssdna/ Au SDS MB i p E p E pc dsdna2s/ Au ssdna2s/ Au 1 E pa E f MB ssdna2s/ ssdna Au MB dsdna2s/ Au i p [22] MB SDS E p E pa E pc ssdna2 [19] MB S/ Au E pa E pc MB MB MB DNA DNA MB ssdna2s/ Au E f i p 15 mv dsdna2s/ Au 16 mv DNA DNA MB ssdna dsdna ssdna dsdna [ ] ssdna (15 bp dsdna 511 nm) 1 MB Table 1 Electrochemical parameters observed in 5 mmol/ L phosphate buffer (ph 619) containing 10 mol/ L (for bare Au) or 5 mol/ L MB (for DNA2S/ Au) Electrode E pa / V 1 E pc / V 2 i pa / A 3 i pc / A 4 E a f / V 5 E p / V Bare Au ssdna2s/ Au dsdna2s/ Au a E f = ( E pa + E pc ) / 21 The E pa E pc i pa i pc and E f are the mean value of 8 measurements with different electrodes on different day1 from 1 to 5 are the standard deviation of E pa E pc i pa i pc and E f respectively1 Other conditions are as in Figure 11

4 No 1 : DNA 25 2 ssdna2s/ Au MB Table 2 Electrochemical parameters obtained at ssdna2s/ Au SDS DTAC CTAB CPB OPB Triton X2100 Tween280 c/ ( mol L - 1 ) E pa / V E pc / V i pa / A i pc / A E f / mv E p / mv or V 3 / L E f denotes the difference of formal potential in the presence and in the absence of surfactant Other conditions are as in Figure 1 DNA SDS ssdna ssdna nm [23] SDS SDS ssdna 015 nm 211 nm [24] SDS ssdna SDS ssdna MB SDS SDS ssdna

5 26 Vol dsdna2s/ Au MB Table 3 Electrochemical parameters obtained at dsdna2s/ Au SDS DTAC CTAB CPB OPB Triton X2100 Tween280 c/ ( mol L - 1 ) E pa / V E pc / V i pa / A i pc / A E f / mv E p / mv or V 3 / L The conditions are as in Table 2

6 No 1 : DNA 27 3 Fe (CN) - 6 ssdna2 S/ Au Figure 3 Complex plane impedance spectra for 015 mmol/ L K 4 Fe2 (CN) 6 / 015 mmol/ L K 3 Fe (CN) 6 in the absence ( ) or presence of surfactant ( ) (a) mol/ L SDS ( ) mol/ L CTAB ( ) and mol/ L DTAC ( ) ; (b) mol/ L CPB ( ) and mol/ L OPB ( ) from top to bottom1 Electrolyte : 20 mmol/ L phosphate buffer (ph 619) ssdna2s/ Au E f E p 3 ssdna dsdna Fe (CN) - 6 DNA/ Au SDS MB ( ) R ct SDS DNA CPB MB dsdna2 DNA S/ Au i pa ssdna2s/ Au i pc ssdna dsdna dsdna MB dsdna DTAC MB i p CPB i pc CPB DTAC dsdna CPB ssdna ssdna MB red MB dsdna MB i pa CPB DTAC DTAC dsdna MB red DNA MB DNA i pa DTAC MB dsdna2s/ Au i p DTAC MB E p i pa 250 mol/ L ssdna2s/ Au DTAC E p CTAB i pc i pa E p dsdna ssdna DTAC CPB OPB MB dsdna2s/ Au Tween280 i p E p OPB CPB CTAB i p MB i pc CPB MB i p 3 CTAB CPB R ct OPB DNA DNA Rct CPB CTAB DTAC ssdna CPB CTAB ssdna R ct CTAB CPB OPB MB i pc i pa ( 2) ssdna MB ssdna MB red MB MB SDS2MB MB MB Triton X2100 Tween280 MB( ) DNA MB DNA MB [22] i pa i pc E p ; i p E p Tween280 dsdna2s/ Au MB 3 Fe (CN) - 6 DNA ( ) DNA DNA Fe ( CN) - 6 DNA Fe (CN) - 6 MB

7 28 Vol : DNA 11 Labuda J ; Buckova M ; Jantova S ; Fresenius J Anal ; DNA Chem ; DNA 12 Hayakawa K ; Santerre J DNA Chem P ; Kwak J C T Biophys 13 Wei W ; Yeung E S Anal Chem [22] DNA DNA 14 Wang L L ; Yoshida J ; Ogata N Chem Mater Yoshikawa K Advanced Drug Delivery Reviews DNA 16 Angerstein2kozlowska H ; Conway B E ; Hamelin A ; References 1 Cater M T ; Bard A J J Am Chem Soc Cater M T ; Rodoriguez M ; Bard A J J Am Chem Soc Rodoriguez M ; Bard A J Anal Chem Vrana O ; Brabec V Bioelectrochem Bioenerg Shen H2B ; Kang Y2Z ; Yang H2F ; Yu L ; Zhang Z2 R Chin J Electrochem (4) 400 (in Chinese) ( (4) 400 ) 6 Zhao G2C ; Zhu J 2J ; Zhang J 2J ; Chen H2Y Anal Chim Acta Pang D W ; Abruna H D Anal Chem Pang D W ; Abruna H D Anal Chem Labuda J ; Buckova M ; Vanickova M ; Mattusch J ; Wennrich R Electroanal (2) Lisdat F ; Ge B ; Krausse B ; Ehrlich A ; Biener H ; Scheller W Electroanal (15) 1225 Stoichviciu L J Electroanal Chem Ci Y 2X ; Yang L2M Chin Sci Bull (16) 980 (in Chinese) ( (16) 980 ) 18 Zheng Y2X Fenxi Shiyanshi (5) 1 (in Chinese) ( (5) 1 ) 19 He X 2W ; Li H Fenxi Shiyanshi (1) 7 ( in Chinese) ( (1) 7 ) 20 Erdem A ; Kerman K ; Meric B ; Ozsoz M Electroanal (3) Kelley S O ; Barton J K Bioconjugate Chem Li L2S ; Huang W2D ; Wang L2P ; Yan Y Acta Chim Sinica (1) 98 (in Chinese) ( (1) 98 ) 23 Whitesides P E ; Laibins P E Langmuir Zhao G2X Physical Chemistry of Surfactants Peking University Press Beijing 1991 p 77 (in Chinese) ( 1991 p 77 ) (A SHEN H )