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Updated: Dec 20, 2025
Design and Development of Aptamer–Gold Nanoparticle Based Colorimetric Assays for In-the-field Applications
Published on: June 23, 2016
An aptasensor strip-based colorimetric determination method for kanamycin using cellulose acetate nanofibers
Mohammed Awad Abedalwafa1,2, Zhimin Tang1, Yansha Qiao1
1Key Laboratory of Textile Science & Technology, Ministry of Education, College of Textiles, Donghua University, Shanghai, 201620, China.
Abstract:
The preparation of portable colorimetric biosensor strips is described by combining aptamer-immobilized electrospun nanofiber membranes (A-NFMs) with signal probes (DNA-conjugated gold nanoparticles (AuNPs)) for determination of kanamycin (KMC) as a model analyte. The A-NFMs were decorated with complementary single-stranded DNA (cDNA) of KMC aptamer-conjugated AuNPs (cDNA@Au) to get the colorimetric biosensor strips. The constructed biosensor strips showed a significant absorbance decreasing band at 510 nm which induce a visual color change from pink to white when exposed to KMC, with a low detection limit of 2.5 nM (at S/N = 3). The effect is due to disassembling of cDNA@Au from NFMs in the presence of KMC because the aptamer has a higher affinity to KMC than its complementary DNA, which resulted in replacing cDNA@Au with KMC. Satisfactory performance was observed in real sample (drinking water and milk) analysis with a recovery of 98.9-102.2%. The constructed colorimetric biosensor test strips hold great application promise for food safety control. Graphical abstract Schematic representation of biosensor strips for kanamycin detection prepared with the cDNA@Au immobilized aptamer-based cellulose acetate nanofibers.
