Fluorescence array-based sensing of metal ions using conjugated polyelectrolytes.
Array-based sensing offers several advantages for detecting a series of analytes with common structures or properties. In this study, four anionic conjugated polyelectrolytes (CPEs) with a common poly(p-pheynylene ethynylene) (PPE) backbone and varying pendant ionic side chains were designed. The conjugation length, repeat unit pattern, and ionic side chain composition were the main factors affecting the fluorescence patterns of CPE polymers in response to the addition of different metal ions. Eight metal ions, including Pb(2+), Hg(2+), Fe(3+), Cr(3+), Cu(2+), Mn(2+), Ni(2+), and Co(2+), categorized as water contaminants by the Environmental Protection Agency, were selected as analytes in this study. Fluorescence intensity response patterns of the four-PPE sensor array toward each of the metal ions were recorded, analyzed, and transformed into canonical scores using linear discrimination analysis (LDA), which permitted clear differentiation between metal ions using both two-dimensional and three-dimensional graphs. In particular, the array could readily differentiate between eight toxic metal ions in separate aqueous solutions at 100 nM. Our four-PPE sensor array also provides a practical application to quantify Pb(2+) and Hg(2+) concentrations in blind samples within a specific concentration range.
†Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.|‡The Ministry-Province Jointly Constructed Base for State Key Lab- Shenzhen Key Laboratory of Chemical Biology, the Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, P. R. China.
Yi
Y
Wu
‡The Ministry-Province Jointly Constructed Base for State Key Lab- Shenzhen Key Laboratory of Chemical Biology, the Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, P. R. China.
Ying
Y
Tan
†Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China.|‡The Ministry-Province Jointly Constructed Base for State Key Lab- Shenzhen Key Laboratory of Chemical Biology, the Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, P. R. China.
Jiatao
J
Wu
§Bioinformatics and Drug Design Group, Department of Pharmacy, National University of Singapore, Singapore 117543, Singapore.
Shangying
S
Chen
§Bioinformatics and Drug Design Group, Department of Pharmacy, National University of Singapore, Singapore 117543, Singapore.|∥Shenzhen Kivita Innovative Drug Discovery Institute, Shenzhen 518055, P. R. China.
Yu Zong
YZ
Chen
⊥Institute of Biomedical Sciences, Fudan University, Shanghai 200433, P. R. China.
Xinwen
X
Zhou
‡The Ministry-Province Jointly Constructed Base for State Key Lab- Shenzhen Key Laboratory of Chemical Biology, the Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, P. R. China.
Yuyang
Y
Jiang
‡The Ministry-Province Jointly Constructed Base for State Key Lab- Shenzhen Key Laboratory of Chemical Biology, the Graduate School at Shenzhen, Tsinghua University, Shenzhen 518055, P. R. China.
Chunyan
C
Tan
D005456:Fluorescent Dyes / Q000737:chemistry; D008670:Metals / Q000032:analysis*; D046228:Microarray Analysis / Q000295:instrumentation / Q000379:methods*; D011108:Polymers / Q000737:chemistry
D005456:Fluorescent Dyes; D008670:Metals; D011108:Polymers; C473966:poly(phenylene ethynylene)
LDA; conjugated polyelectrolytes; metal ion; poly(p-pheynylene ethynylene); sensor array