A new Co-based GO nanoflower combined with dummy molecularly imprinted polymer for micro-solid phase extraction of cortisol from water and biological fluids

ÖZALP Ö., SOYLAK M.

Journal of the Indian Chemical Society, cilt.103, sa.6, 2026 (SCI-Expanded, Scopus) identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 103 Sayı: 6
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.jics.2026.102651
  • Dergi Adı: Journal of the Indian Chemical Society
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, EMBASE
  • Anahtar Kelimeler: Cortisol, Dummy template, Hydrocortisone, Micro solid phase extraction, Molecularly imprinted polymers, UV-Vis spectrophotometer
  • Erciyes Üniversitesi Adresli: Evet

Özet

In this work, a new colorimetric cortisol detection approach was developed using a molecularly imprinted polymer (MIP) supported by a cobalt-based graphene oxide nanofiber (Co-GO NFs). The approach is a combination of the Prussian Blue (PB) reaction with micro-solid phase extraction (μSPE) for excellent selectivity, precision, and accuracy, as well as a high enrichment factor in hydrocortisone analysis. Critical parameters, such as temperature (optimal at 90–100 °C) and solvent composition (ethanol-based), were carefully optimized to improve reaction rate and facilitate a rapid and visually perceptible color shift within 15 min. The approach exhibited an extensive linear response range of 6.08–1000 ng mL−1, a minimal detection limit of 1.82 ng mL−1, and a high enrichment factor of 50. The selectivity of the μSPE technique was additionally tested in the presence of interfering ions and structurally similar chemicals, which demonstrated quantitative recovery of hydrocortisone from both synthetic and actual urine and saliva samples. The results obtained confirm the effectiveness of the synthesized Co-GO NFs@MIP as a reliable colorimetric system for cortisol determination in biological applications.