Highly sensitive antimonene-coated black phosphorous-based surface plasmon-resonance biosensor for DNA hybridization: design and numerical analysis

The design of an ultrasensitive surface plasmon resonance (SPR) sensor for the detection of deoxyribose nucleic acid (DNA) hybridization is highly desirable for biomedical applications. We have proposed an SPR sensor architecture (Prism-SF10/Al/Si/BP/Antimonene/phosphate buffer saline solution) and performed its numerical analysis for DNA hybridization using angular interrogation at 633 nm. Antimonene is used as a biorecognition element layer for better attachment of single stranded (ss), i.e., ss probe DNA on its surface, due to its higher binding energy for ssDNA (even greater than graphene). Silicon and black phosphorous are utilized to enhance the electromagnetic field at the sensing layer interface. Aluminum is used as an surface plasmon active metal and it also improves the quality factor. Remarkable sensitivity (202.37 deg / refractive index unit) is attained for this work, which is greater than any other SF10 prism-based SPR sensor proposed to date. The performance of the SPR biosensor is meticulously evaluated as limit-of-detection (0.0028 nM) and figure-of-merit (0.037 nM − 1) with respect to the concentration of complementary target ssDNA in the sensing medium. This versatile biosensor shows great application to detect deadly diseases via DNA hybridization in the biomedical field if developed as an SPR chip for experimental verification.