38 2010 10 FENXI HUAXUE Chinese Journal of Analytical Chemistry 10 1405 ~ 1410 DOI 10. 3724 /SP. J. 1096. 2010. 01405 CdSe Hg? * 510631 D- L- CdSe Hg? Hg? Cd 2 + HSe - D-Pen L-Cys 1 0. 25 2 1. 2 ph = 7. 5 TEM CdSe 50 80 nm ph 7. 38 CdSe 516 nm Hg? Hg? 40 pmol /L Hg? 96. 7% ~ 102. 5% CdSe D- L- 1 1 2 CdSe 3 4 L- 5 CdSe 6 CdS L- D- Li 7 CdTe 8 CdTe Cu 2 + Hg? 5 L- CdSe Hg? 1 Wang 9 PDDA /MSA CdTe Hg? Ni 2 + Co 2 + Pb 2 + Long DNA CdS /DNA NPs 10 CdS / DNA 5 D- D-Pen CdSe /D-Pen L- L-Cys CdSe /D-Pen /L-Cys Hg? Hg? 2 2. 1 F-2500 FLS-920 Eeinburgh AFS-230E 99. 95% NaBH 4 96. 0% CdCl 2 2. 5H 2 O 99. 0% D- 99. 0% Avocado Research Chemicals L- 98% 2010-01-12 2010-02-14 No. 20975041 No. 7005803 * E-mail yuyhs@ 163. com
1406 38 Hg NO 3 2 1 /2 H 2 O 97. 0% HNO 3 114 mg /L 0. 0114 g Hg NO 3 2 HNO 3 0. 5 ml 100 KH 2 PO 4 -Na 2 HPO 4 Britton- Robinson Tris-HCl 2. 2 2. 2. 1 CdSe /D-Pen /L-Cys 0. 0188 g 0. 082 mmol CdCl 2 2. 5H 2 O 0. 0246 g 0. 164 mmol D-Pen 100 ml 1 mol /L NaOH ph 7. 5 15 min 42 μl 0. 5 mol /L 0. 021 mmol NaHSe 80 15 min D-Pen CdSe 40 ml 2. 5 mmol /L 0. 1 mmol L-Cys CdSe 60 30 min CdSe /D-Pen /L-Cys 2. 2. 2 Hg? 0. 20 ml CdSe /D-Pen /L-Cys 0. 20 ml ph = 7. 38 Hg? 5. 0 mlλ ex /λ em 283 /516 nm CdSe /D-Pen /L-Cys-Hg? 3 3. 1 CdSe CdSe CdSe /L-Cys CdSe /L-Cys /D- Pen CdSe /D-Pen CdSe /D-Pen /L-Cys 1 CdSe /D-Pen /L-Cys D-Pen CdSe /D-Pen L-Cys CdSe /D-Pen /L-Cys 3. 2 CdSe /D-Pen /L-Cys CdSe /D-Pen /L-Cys Cd 2 + HSe - D- Pen L-Cys 1 0. 25 2 1. 2 ph 7. 5 1 CdSe 30 min 60 2 Fig. 1 Effect of different stabilizers on CdSe CdSe /D-Pen CdSe /D-Pen /L-Cys nanocrystals fluorescence 50 80 nm Molar ratio of reactants 1. Cd 2 + 3. 3 CdSe HSe - D-penicillamine D-Pen L-cysteine L-Cys = 3 1 0. 25 2 1. 2 2. Cd 2 + HSe - L-Cys D-Pen = CdSe /L-Cys 1 0. 25 1. 2 2 3. Cd 2 + HSe - L-Cys = 1 0. 25 1. 2 1 4. Cd 2 + HSe- D-Pen = 1 0. 25 2 CdSe /D-Pen CdSe /L-Cys 2 CdSe / D-Pen /L-Cys 4 3. 4 CdSe /D-Pen /L-Cys CdSe /D-Pen /L-Cys Effq = F 0 - F /F 0 CdSe /D-Pen /L-Cys F F 0 4 Hg? Cu 2 + CdSe /D-Pen /L- Cys Hg? CdSe /D-Pen /L-Cys 0. 77 Cu 2 + CdSe 0. 32 ph 7. 38 0. 032 ph 7. 38 Hg? CdSe /D-Pen /L-Cys CdSe /D-Pen /L-Cys Hg?
10 CdSe Hg? 1407 3. 5 CdSe /D-Pen /L-Cys -Hg? 5 Hg? CdSe /D-Pen /L-Cys Hg? 0 ~ 25. 2 nmol /L CdSe Hg? 25. 2 nmol /L CdSe CdSe /D-Pen /L-Cys 516 nm 2 CdSe /D-Pen A CdSe /D-Pen /L-Cys B3 Fig. 3 Fig. 2 TEM image of CdSe /D-Pen A and CdSe /D-Pen / L-Cys B nanocrystals CdSe Effect of stabilizers on fluorescence stability 1. CdSe /D-Pen /L-Cys 2. CdSe /D-Pen 3. CdSe /L-Cys. 4 CdSe /D-Pen /L-Cys 5 Hg? CdSe Fig. 5 Effect of Hg? concerntration on fluorescence Fig. 4 Quenching effect of different metal ions on CdSe / intensity of CdSe nanocrystals D-Pen / L-Cys nanocrystals C Metal ions 1. 8 μmol /L C CdSe 15 μmol /L. Hg? a ~ h 0 0. 8 1. 6 2. 4 3. 2 4. 0 4. 8 25. 2 6. 0 μmol /L CdSe nanocrystals. 3. 6 CdSe /D-Pen /L-Cys Hg? 3 KH 2 PO 4 -Na 2 HPO 4 Britton-Robinson Tris-HCl 0. 20 ml ph 7. 38 10 min 3. 7 6 3. 0 4. 5 6. 0 μmol /L Hg? 9. 0 10. 5 μmol /L 1 3δ /k δ 10 k 6. 0 μmol /L
1408 38 1 CdSe /D-Pen /L-Cys -Hg? Table 1 Linear equations and linear range of CdSe /D-Pen /L-Cys nanocrystals NCs -Hg? Concentration Linear range Detection of NCs Linear equation R limit μmol /L 4. 5 ΔF = 649. 4C + 103. 6 0. 2 ~ 2. 8 0. 9930 0. 05 6. 0 ΔF = 708. 4C + 142. 7 0. 16 ~ 4. 8 0. 9965 0. 04 9. 0 ΔF = 279. 5C + 60. 3 0. 44 ~ 12. 0 0. 9960 0. 11 10. 5 ΔF = 87. 8C + 92. 6 1. 36 ~ 36. 0 0. 9956 0. 34 2 6 CdSe /D-Pen /L-Cys Mg 2 + K + Mn 2 + Na + Al 3 + Fe 2 + Zn 2 + Cd 2 + Cu 2 + Ni 2 + Fig. 6 Effect of concerntration of CdSe /D-Pen / Cu 2 + Ni 2 + Hg? L-Cys NCs solution on sensitivity and linear range NCs μmol /L Δ 3. 0 4. 5 6. 0 9. 0 500 1000 10. 5. 2 Table 2 Interference of coexisting substances Coexisting ions Tolerance ratios 10 3 Relative error Coexisting ions Tolerance ratios 10 3 Mg 2 + 15-3. 3 Ag + 4. 5-5. 8 Al 3 + 44. 5-5. 5 Zn 2 + 11. 5 5. 5 Ca 2 + 6-5. 6 Pb 2 + 7-2. 4 Fe 2 + 15-4. 0 Cu 2 + 0. 5-5. 1 K + 82-4. 9 Cd 2 + 10. 5-5. 0 Cr 3 + 6-3. 7 Co 2 + 3-6. 0 Mn 2 + 400-5. 2 Ni 2 + 1-5. 4 Na + 102-4. 8 Ba 2 + 9. 5-5. 5 3. 8 Relative error 4. 0 ml 3 2. 2. 2 3 3 AFS 3 Table 3 Determination results of real samples Samples AFS* This method RSD Added This method Average recovery Pure water 0. 10 0. 13 0. 14 0. 13 4. 4 0. 4 0. 53 0. 57 0. 50 100 Drinking water 0. 15 0. 18 0. 19 0. 20 5. 3 0. 4 0. 59 0. 60 0. 61 102. 5 Tap water 0. 20 0. 22 0. 21 0. 24 6. 9 0. 4 0. 60 0. 58 0. 67 98. 3 River water 0. 30 0. 31 0. 30 0. 29 3. 3 0. 4 0. 68 0. 69 0. 69 96. 7 * Tested by Guangzhou Environmental Monitoring Center Station Unknow sample 4 Hg? 4 MAA- InP L-Cysteine CdSe Hg? 5. 2% Cu? Hg? 50 CdTe /TGA NPs dbsa Hg?
10 CdSe Hg? 1409 4 Hg? Table 4 Comparison of linear range and detection limit of different methods for detection of Hg? Reagent / λ ex /λ Linear range em LOD Reference InP /MAA 750 /826 2500 ~ 39800 997 11 CdSe /L-Cysteine 430 /630 0 ~ 1250 4. 5 5 CdTe /TGA /dbsa 380 /541 12 ~ 1500 4. 0 13 CdSe /D-Pen /L-Cys 283 /516 0. 16 ~ 4. 8 1. 36 ~ 36 0. 04 0. 34 This method 3. 9 Hg? CdSe Hg? CdSe Stern-Volmer F 0 /F = 1 + K SV Q Stern-Volmer log F 0 /F = K SV Q + C F 0 F Q Hg? K SV C Q 0 ~ 4. 8 nmol /L F 0 /F ~ Q R = 0. 9794 log F 0 /F ~ Q R = 0. 9980 Hg? Stern-Volmer 10 14 HgSe K SP 1. 0 10-60 CdSe K SP = 6. 31 10-36 24 15 Hg? CdSe /D-Pen /L-Cys Se II HgSe CdSe /D-Pen /L-Cys CdSe /D-Pen / L-Cys CuSe K SP 1. 0 10-49 CdSe K SP Cu? Hg? CuSe K SP HgSe Cu? Hg? Stern-Volmer References 1 LIU Di CHENG Wei-Qing YAN Zheng-Yu. Chinese J. Anal. Chem. 2007 35 6 825 ~ 829 2 MEI Fang HE Xi-Wen LI Juan LI Wen-You ZHANG Yu-Kui. Acta Chimica Sinica 2006 64 22 2265 ~ 2270 3 Celeste A C Kerim M G Sarita V M Gema C Vipin R Cheng Tu-Chen Joseph J D Roger M L. J. Phys. Chem. B 2003 107 50 13762 ~ 13764 4 XU Wan-Bang WANG Yong-Xian LIANG Sheng XU Rong-Hui ZHANG Guo- Xin YIN Rui-Zhi. Chinese J. Inorg. Chem. 2007 23 7 1220 ~ 1226 5 Chen J L Gao Y C Guo C Wu G H Chen Y C Lin B W. Spectrochim. Acta Part A 2008 69 2 572 ~ 579 6 Moloney M P Gun'ko Y K Kelly J M. Chem. Commun. 2007 38 3900 ~ 3902 7 Li J Hong X Li D Zhao K Wang L Wang H Z Du Z L Li J H Bai Y B Li T J. Chem. Commun. 2004 15 1740 ~ 1741 8 ZHENG Ai-Fang CHEN Jin-Long. Journal of Inorganic Materials 2009 24 2 251 ~ 254 9 Wang C Zhao J W Wang Y Lou N Ma Q Su X G. Sensors and Actuators B 2009 139 2 476 ~ 482 10 Long Y F Jiang D L Zhu X Wang J X Zhou F M. Anal. Chem. 2009 81 7 2652 ~ 2657 11 Zhu C Q Li L Fang F Chen J L Wu Y Q. Chem. Lett. 2005 34 7 898 ~ 899 12 Xia Y S Zhu C Q. Talanta 2008 75 1 215 ~ 221 13 CHEN Guo-Zhen HUANG Xian-Zhi ZHENG Zhu-Zi XU Jin-Gou WANG Zun-Ben. Methods of Fluorescence Analysis 2nd Ed. Beijing Science Press 1990 118 ~ 120
1410 38 14 Division of Analytical Chemistry Department of Chemistry Hangzhou University. Handbook of Analytical Chemistry?. Beijing Chemical Industry Press 1979 57 Synthesis of Chiral Dual-stabilizer Capped CdSe Nanocrystals and Its Application to Selective Detection of Hg? CHEN Guo-Min YU Ying * HU Xiao-Gang CAO Yu-Juan WU Jian-Zhong Department of Chemistry and Environment South China Normal University Guangzhou 510631 Abstract Dual-stabilizer D-Penicillamine D-Pen and L-Cysteine L-Cys capped CdSe nanocrystals were prepared by direct aqueous synthesis method and trace Hg? have a significantly quenched their fluorescence intensity. A new method for the determination of trace Hg? was established based on this. When ph is 7. 5 and molar ratio of Cd 2 + HSe - D-Pen L-Cys is 1 0. 25 2 1. 2 CdSe /D-Pen /L-Cys has a better luminescent strength and stability than CdSe / D-Pen and CdSe / L-Cys. TEM shows that the CdSe nanocrystals are spherical particles and the sizes of the particles are about 50 nm and 80 nm respectively. In the phosphate buffer solution at ph 7. 38 maximum fluorescence peak of CdSe /D-Pen /L-Cys was at 516 nm the fluorescence could be quenched significantly and selectively by Hg?. The fluorescence quenching was proportional to the concentration of Hg? a detection limit of 40 pmol /L was achieved. The method was applied to the determination of Hg? in different water samples and the results were in a good agreement with those obtained by the standard method. The average recovery was 96. 7% - 102. 5%. Keywords Cadmium selenide nanocrystals D-Penicillamine L-Cysteine Mercury? Fluorescence quenching Received 12 January 2010 accepted 14 February 2010 櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗櫗 2010 8 19-22 840 120 1200 122 800 8 6 100 10 3 http / /www. chem. pku. edu. cn /smfxhx /