Microchimica Acta

, 186:130 | Cite as

Cysteine capped copper/molybdenum bimetallic nanoclusters for fluorometric determination of methotrexate via the inner filter effect

  • Yowan Nerthigan
  • Amit Kumar Sharma
  • Sunil Pandey
  • Hui-Fen WuEmail author
Original Paper


A method is reported for the synthesis of highly luminescent copper/molybdenum bimetallic nanoclusters (Cu/Mo NCs) using cysteine as both a capping and reducing agent. The nanoclusters display bluish-green luminescence (excitation/emission peaks at 370/490 nm) and a relative quantum yield of 26%. The capped Cu/Mo NCs were used as a fluorescent probe for determination of the antineoplastic drug methotrexate (MTX) via an inner filter effect. Fluorescence intensity decreases linearly in the 50 nM to 100 μM MTX concentration range. The limit of detection is 13.7 nM. This approach has been successfully applied to the determination of MTX in spiked human urine with a typical recovery of 99%.

Graphical abstract

Schematic of a fluorometric method for the determination of methotrexate (MTX) which exerts a strong inner filter effect on the fluorescence of cysteine-capped copper/molybdenum nanoclusters (CuMo NCs) at the wavelength of excitation (370 nm).


Bimetallic nanoclusters Nanoclusters Inner filter effect Capping Urine analysis 



We express our gratitude to the Ministry of Science and Technology (MOST), Taiwan for the financial assistance with the grant number of MOST 107-2113-M-110-011-MY3.

Compliance with ethical standards

The author(s) declare that they have no competing interests.

Supplementary material

604_2019_3230_MOESM1_ESM.docx (951 kb)
ESM 1 (DOCX 950 kb)


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Copyright information

© Springer-Verlag GmbH Austria, part of Springer Nature 2019

Authors and Affiliations

  • Yowan Nerthigan
    • 1
  • Amit Kumar Sharma
    • 1
  • Sunil Pandey
    • 1
  • Hui-Fen Wu
    • 1
    • 2
    • 3
    • 4
    Email author
  1. 1.Department of ChemistryNational Sun Yat-Sen UniversityKaohsiungTaiwan
  2. 2.School of Pharmacy, College of PharmacyKaohsiung Medical UniversityKaohsiungTaiwan
  3. 3.Doctoral Degree Program in Marine BiotechnologyNational Sun Yat-Sen University and Academia SinicaKaohsiungTaiwan
  4. 4.Institute of Medical Science and TechnologyNational Sun Yat-Sen UniversityKaohsiungTaiwan

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