Label-free, disposable fiber-optic biosensors for DNA hybridization detection

作者：Yin M J^*; Wu C; Shao L Y; Chan W K E; Zhang A P; Lu C; Tam H Y

来源：ANALYST, 2013, 138(7): 1988-1994.

DOI：10.1039/c3an36791f

A novel and highly sensitive fiber-optic DNA sensor based on a thin-core fiber modal interferometer (TCFMI) is demonstrated by using a layer-by-layer (LbL) self-assembly technology. Poly(ethylenimine) (PEI), poly(acrylic acid) (PAA) and single-stranded DNA (ssDNA) were used for the preparation of a polyelectrolyte multilayer film for DNA detection. The film thickness was measured through a surface profilometer. The surface morphologies of (PEI/PAA)4, (PEI/PAA)4.5 and (PEI/PAA)4(PEI/ DNA)1 multilayer films were characterized by atomic force microscopy. The fabricated DNA sensors were tested with different types of target ssDNA solutions with a concentration of 1 μM. The results show that the sensitivity of the TCFMI-based ssDNA sensor is 0.27 nm/matched-base at the concentration of 1 μM and can even distinguish the number of matched bases of ssDNA chains.

• 单位
  香港理工大学