Determination of prostate cancer marker Zn2+ with a highly selective surface-enhanced Raman scattering probe on liquid–liquid self-assembled Au nanoarrays

• Published in: Talanta (Oxford) 2020-03, Vol.209, p.120569-120569, Article 120569
• Main Authors: Teng, Yuanjie, Ren, Zeyu, Zhang, Yuchao, Wang, Zhenni, Pan, Zaifa, Shao, Kang, She, Yuanbin
• Format: Article
• Language: English
• Subjects: Au nanoarray; Liquid-liquid self-assembly; Prostate cancer; SERS; Zincon; Zn2
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2019.120569

As the concentration of Zn2+ in patients with prostate cancer is much less than that in healthy persons, Zn2+ concentration can be used as a marker to expediently screen prostate cancer. In this study, a sensitive and highly selective surface-enhanced Raman scattering (SERS) method to detect Zn2+ concentration in human prostatic fluids by utilizing water-insoluble 2-carboxyl-2′-hydroxyl-5′-sulfoformazylbenze (Zincon) as a SERS probe based on self-assembled Au nanoarrays at a liquid–liquid interface between n-hexane and Au colloids was proposed. Zincon showed remarkably different SERS bands before and after coordinating Zn2+ in the controlled conditions (70 μL of ethanol, 500 μL of n-hexane, pH value of 7.1 and 10 s of vortex mixing time), which can be used in quantifying Zn2+ with characteristic peaks. The proposed SERS method presented a good linear relationship ranging from 0.5 to 10 μmol/L and a satisfactory detection limit of 0.1 μmol/L as well as low interference with other metal ions. Moreover, the detection results are close to those of the conventional standard atomic absorption spectroscopy (AAS) method. Based on liquid-liquid self-assembled Au nanoarrays, water-insoluble dye Zincon and its complex Zincon-Zn2+ can be detected by SERS. Meanwhile, the binding of Zn2+ with Zincon was identified detailed in both normal Raman and SERS spectra. Therefore, Zincon as a selective SERS probe was applied to sensitive Zn2+ detection. [Display omitted] •Fabrication of liquid-liquid self-assembled Au nanoarrays for realizing the SERS detection of water-insoluble Zincon and Zincon-Zn2+ complex.•The characteristic peaks of Zincon and Zincon-Zn2+ complex were assigned by theoretical calculation.•Zincon as a selective SERS probe can be applied to the sensitive detection of prostate cancer marker Zn2+.