What question did this study set out to answer?

The aim is to develop a novel colorimetric nanosensor for the sensitive and selective detection of safranal in saffron.

May 31, 2026Open Access

Design and validation of a plasmon-based colorimetric nanosensor for the sensitive/selective detection of safranal and preventing adulteration of saffron

Key Points

The aim is to develop a novel colorimetric nanosensor for the sensitive and selective detection of safranal in saffron.
Developed plasmonic nanosensors using bacterial cellulose nanofibers functionalized with silver nanoparticles and graphene oxide.
Conducted selectivity tests and analyzed color shifts (CIELab ΔE) after exposing sensors to safranal and other solutions.
Measured limits of detection and compared performance between sensor types.
PNSG1 achieved a limit of detection of 9 ppmv for safranal, significantly lower than the Ag-only sensor's 14 ppmv.
Sensory performance reflected in ΔE values: PNSG1 showed 10.03 for safranal compared to Ag-only's 7.33.
PNSG series demonstrated better mechanical properties and enhanced selectivity for safranal detection.

Abstract

This work presents a novel colorimetric platform for safranal (SAF) detection using plasmonic nanosensors (PNS) composed of bacterial cellulose nanofibers (BCNF) functionalized with silver nanoparticles (AgNPs) and single-layer graphene oxide (GO). Synthesized GO exhibited an average thickness of 0.9 nm. BCNF, with a 35 nm diameter and ˃10 µm length, demonstrated robust mechanical strength (198 MPa) and thermal stability (300 °C). A control sensor (AgNP-only PNS) was fabricated using AgNPs derived from 0.1% silver nitrate, confirmed by UV-Vis spectroscopy with a localized surface plasmon resonance (LSPR) peak at 450 nm. For enhanced performance, BCNF were treated with GO (25-100 μg/mL) and immobilized with AgNPs (PNSG1-PNSG4). These GO-integrated sensors (PNSG series) displayed superior tensile strength (1.25–1.29 GPa) and Young’s modulus (173–187 MPa) compared to AgNP-only counterparts. Exposure to SAF (1–25 μL, 19.32–483 ppmv) over 12–72 h induced quantifiable color shifts analyzed via CIELab ΔE values. ΔE increased linearly with SAF concentration, plateauing near ΔE ≈ 10. Among all sensors, PNSG1 achieved the lowest limit of detection (LOD = 9 ppmv, RSD = 12.29%), outperforming the Ag-only sensor (LOD = 14 ppmv, RSD = 11.41 Selectivity tests revealed distinct responses: the Ag-only PNS yielded ΔE = 4.53 (acetic acid), 6.3 (acetaldehyde), and 7.33 (SAF), while PNSG1 showed enhanced discrimination with ΔE = 10.03 (SAF), 8.55 (acetaldehyde), and 7.66 (acetic acid). PNSG1 combines exceptional flexibility, mechanical resilience, and sensitivity for SAF detection, making it a promising tool for non-destructive food quality assessment, especially in verifying saffron purity and identifying adulterants.

Read Full Paperexternally

Bookmark

View Full Paper

Cite This Study

Mohammadi et al. (Fri,) studied this question.

synapsesocial.com/papers/6a1bcfe15783ba022b6fbca8 https://doi.org/https://doi.org/10.1016/j.fufo.2026.101062

Bookmark

View Full Paper