title: Carbon dots as a fluorescent probe for label-free detection of physiological potassium level in human serum and red blood cells.
abstract: A unique photoluminescence carbon dots (CDs) with larger size were prepared by microwave-assisted method. Complex functional groups on the surface of the CDs facilitate the nanoparticles to form affinity with some metal ions. Taking advantage of the effective fluorescence quenching effect of K(+), a highly sensitive CD-based fluorescence analytical system for label-free detection of K(+) with limit of detection (LOD) 1.0×10(-12) M was established. The concentrations of potassium ion in biological samples such as human serum are usually found at millimolar levels or even higher. The proposed method begins with a substantial dilution of the sample to place the K(+) concentration in the dynamic range for quantification, which covers 3 orders of magnitude. This offers some advantages: the detection of K(+) only needs very small quantities of biological samples, and the dilution of samples such as serum may effectively eliminate the potential interferences that often originate from the background matrix. The determined potassium levels were satisfactory and closely comparable with the results given by the hospital, indicating that this fluorescent probe is applicable to detection of physiological potassium level with high accuracy. Compared with other relative biosensors requiring modified design, bio-molecular modification or/and sophisticated instruments, this CD-based sensor is very simple, cost-effective and easy detection, suggesting great potential applications for successively monitoring physiological potassium level and the change in biological system.
authors.affiliation: School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Hunan Provincial University Key Laboratory of QSAR/QSPR, Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, Xiangtan, China.
authors.forename: Lingyang
authors.initials: L
authors.lastname: Zhang
authors.affiliation: School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Hunan Provincial University Key Laboratory of QSAR/QSPR, Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, Xiangtan, China.
authors.forename: Shenna
authors.initials: S
authors.lastname: Chen
authors.affiliation: School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Hunan Provincial University Key Laboratory of QSAR/QSPR, Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, Xiangtan, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: School of Chemistry and Chemical Engineering, Hunan University of Science and Technology, Hunan Provincial University Key Laboratory of QSAR/QSPR, Key Laboratory of Theoretical Organic Chemistry and Function Molecule, Ministry of Education, Xiangtan, China. Electronic address: hhwn09@163.com.
authors.forename: Haowen
authors.initials: H
authors.lastname: Huang
mesh_terms: D002244:Carbon / Q000737:chemistry*; D004912:Erythrocytes / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007477:Ions / Q000737:chemistry; D011188:Potassium / Q000032:analysis* / Q000097:blood; D045663:Quantum Dots / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
chemical_list: D005456:Fluorescent Dyes; D007477:Ions; D002244:Carbon; D011188:Potassium
keywords: Carbon dots; Human red blood cells; Human serum; Label free; Potassium ion