Ultratrace Detection of Nickel(II) Ions in Water Samples Using Dimethylglyoxime-Doped GQDs as the Induced Metal Complex Nanoparticles by a Resonance Light Scattering Sensor

Nipaporn Pimsin; Niradchada Kongsanan; Chayanee Keawprom; Phitchan Sricharoen; Prawit Nuengmatcha; Won-Chun Oh; Yonrapach Areerob; Saksit Chanthai; Nunticha Limchoowong

doi:10.1021/acsomega.1c00190

Ultratrace Detection of Nickel(II) Ions in Water Samples Using Dimethylglyoxime-Doped GQDs as the Induced Metal Complex Nanoparticles by a Resonance Light Scattering Sensor

ACS Omega. 2021 Jun 2;6(23):14796-14805. doi: 10.1021/acsomega.1c00190. eCollection 2021 Jun 15.

Authors

Nipaporn Pimsin¹, Niradchada Kongsanan¹, Chayanee Keawprom¹, Phitchan Sricharoen², Prawit Nuengmatcha³, Won-Chun Oh⁴, Yonrapach Areerob⁵, Saksit Chanthai¹, Nunticha Limchoowong⁶

Affiliations

¹ Materials Chemistry Research Center, Department of Chemistry and Center of Excellence for Innovation in Chemistry, Faculty of Science, Khon Kaen University, Khon Kaen 40002, Thailand.
² Nuclear Technology Research and Development Center, Thailand Institute of Nuclear Technology (Public Organization), Nakhon Nayok 26120, Thailand.
³ Nanomaterials Chemistry Research Unit, Department of Chemistry, Faculty of Science and Technology, Nakhon Si Thammarat Rajabhat University, Nakhon Si Thammarat 80280, Thailand.
⁴ Department of Advanced Materials Science and Engineering, Hanseo University, Seosan, Chungnam 31962, Republic of Korea.
⁵ Department of Industrial Engineering, Faculty of Engineering, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand.
⁶ Department of Chemistry, Faculty of Science, Srinakharinwirot University, Bangkok 10110, Thailand.

Abstract

This study aimed to synthesize dimethylglyoxime (DMG) (N-source)-doped graphene quantum dots (N-GQDs) via simultaneous pyrolysis of citric acid and 1.0% (w/v) DMG. The maximum excitation wavelength (λ_max, ex = 380 nm) of the N-GQD solution (49% quantum yield (QY)) was a red shift with respect to that of bare GQDs (λ_max, ex = 365 nm) (46% QY); at the same maximum emission wavelength (λ_max, em = 460 nm), their resonance light scattering (RLS) intensity peak was observed at λ_max, ex/em = 530/533 nm. FTIR, X-ray photoelectron spectroscopy, XRD, energy-dispersive X-ray spectroscopy, and transmission electron microscopy analyses were performed to examine the synthesized materials. The selective and sensitive detection of Ni²⁺ using the RLS intensity was performed at 533 nm under the optimum conditions consisting of both 25 mg L^-1 N-GQDs and 2.5 mg L^-1 DMG in the ammonium buffer solution of pH 9.0. The linearity of Ni²⁺ was 50.0-200.0 μg L^-1 with a regression line, y = 5.031x - 190.4 (r ² = 0.9948). The limit of detection (LOD) and the limit of quantitation (LOQ) were determined to be 20.0 and 60.0 μg L^-1, respectively. The method precision expressed as % RSDs was 4.90 for intraday (n = 3 × 3) and 7.65 for interday (n = 5 × 3). This developed method afforded good recoveries of Ni²⁺ in a range of 85-108% when spiked with real water samples. Overall, this innovative method illustrated the identification and detection of Ni²⁺ as a DMG complex with N-GQDs, and the detection was highly sensitive and selective.