Manganese(ii) enhanced fluorescent nitrogen-doped graphene quantum dots: a facile and efficient synthesis and their applications for bioimaging and detection of Hg2+ ions

Li Yang; Aimiao Qin; Shuoping Chen; Lei Liao; Jiangke Qin; Kaiyou Zhang

doi:10.1039/c7ra12133d

Manganese(ii) enhanced fluorescent nitrogen-doped graphene quantum dots: a facile and efficient synthesis and their applications for bioimaging and detection of Hg²⁺ ions

RSC Adv. 2018 Feb 6;8(11):5902-5911. doi: 10.1039/c7ra12133d. eCollection 2018 Feb 2.

Authors

Li Yang¹, Aimiao Qin¹, Shuoping Chen¹, Lei Liao¹, Jiangke Qin², Kaiyou Zhang¹

Affiliations

¹ Key Lab New Processing Technology for Nonferrous Metals & Materials, Ministry of Education, Guangxi Key Laboratory in Universities of Clean Metallurgy and Comprehensive Utilization for Non-ferrous Metals Resources, College of Materials Science & Engineering, Guilin University of Technology Guilin China 592491245@qq.com.
² College of Chemistry and Pharmaceutical Science, Guangxi Normal University Guilin China.

Abstract

Manganese ion (Mn²⁺) bonded nitrogen-doped graphene quantum dots (Mn(ii)-NGQDs) with water solubility have been successfully synthesized by a simple, one-pot hydrothermal carbonization, using sodium citrate, glycine and manganese chloride as raw materials. The photoluminescence (PL) characteristics of Mn(ii)-NGQDs were studied in detail. The resulting Mn(ii)-NGQDs show a remarkably enhanced PL intensity and quantum yield (QY = 42.16%) compared with the product without Mn(ii)-doped (named as NG, QY = 27.06%) and the product doped with other metal ions. The Mn(ii)-NGQDs not only display low toxicity and high cellular uptake efficiency for fluorescence live cell imaging in biological evaluations but also exhibit a fast, highly selective and sensitive fluorescence quenching effect toward Hg²⁺ ions, with a detection limit of 3.4 × 10^-8 mol L^-1.