3D nanoplasmonic biosensor for detection of filopodia in cells. Issue 12 (18th May 2020)

• Record Type: Journal Article
• Authors: Zhu, Shuyan; Eldeeb, Mohammed A.; Pang, Stella W.
• Is Part Of: Lab on a chip. Volume 20:Issue 12(2020)
• Page Start: 2188
• Page End: 2196
• Publication Date: 2020-05-18
• Subjects: Miniature electronic equipment -- Periodicals; Combinatorial chemistry -- Periodicals; Biotechnology -- Periodicals; 543.0813
• DOI: 10.1039/d0lc00173b
• Languages: English
• ISSNs: 1473-0197

Abstract

Abstract : Filopodia detection using nanoplasmonic biosensors, where microposts were used to separate the cell membrane from filopodia and 3D nanopillars were used to monitor nanometer-sized filopodia. Abstract : Filopodia are thin finger-like protrusions from cells and they are hard to detect using electrical, mechanical, or optical sensors because of their nanometer scale features. Besides, the signals from filopodia and the cell membrane are often mixed together which makes the detection of filopodia challenging. Here, a 3D nanoplasmonic biosensor with microposts is proposed to overcome these limitations. By using suitable chemical coating and physical dimensions, the signals from filopodia and the cell membrane were separated by having the microposts keep the cell membrane from making contact with the nanoplasmonic biosensor. The filopodia were detected by the 3D asymmetrical nanopillars with sharp Fano resonance. The sensitivity and figure of merit of the nanoplasmonic biosensor were 650 nm per refractive index unit and 28.3, respectively. A large peak shift of 6 nm was observed for the detection of MC3T3 osteoblastic cell filopodia at a concentration of 1300 cells per mm 2 . To the best of our knowledge, this is the first demonstration of filopodia detection using nanoplasmonic biosensors, where microposts were used to separate the cell membrane from filopodia and the 3D nanoplasmonic biosensors were used to monitor filopodia on the nanometer scale. These combined 3D micro- and nano-structures allow filopodia to be detected using different sensors without interference from the cell membrane.