Optical fiber nanotips coated with molecular beacons for DNA detection.
Optical fiber sensors, thanks to their compactness, fast response and real-time measurements, have a large impact in the fields of life science research, drug discovery and medical diagnostics. In recent years, advances in nanotechnology have resulted in the development of nanotools, capable of entering the single cell, resulting in new nanobiosensors useful for the detection of biomolecules inside living cells. In this paper, we provide an application of a nanotip coupled with molecular beacons (MBs) for the detection of DNA. The MBs were characterized by hybridization studies with a complementary target to prove their functionality both free in solution and immobilized onto a solid support. The solid support chosen as substrate for the immobilization of the MBs was a 30 nm tapered tip of an optical fiber, fabricated by chemical etching. With this set-up promising results were obtained and a limit of detection (LOD) of 0.57 nM was reached, opening up the possibility of using the proposed nanotip to detect mRNAs inside the cytoplasm of living cells.
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. a.giannetti@ifac.cnr.it.
Ambra
A
Giannetti
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. a.barucci@ifac.cnr.it.
Andrea
A
Barucci
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. f.cosi@ifac.cnr.it.
Franco
F
Cosi
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. s.pelli@ifac.cnr.it.|Museo Storico della Fisica e Centro Studi e Ricerche Enrico Fermi, Piazza del Viminale 1, 00184 Rome, Italy. s.pelli@ifac.cnr.it.
Stefano
S
Pelli
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. s.tombelli@ifac.cnr.it.
Sara
S
Tombelli
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. c.trono@ifac.cnr.it.
Cosimo
C
Trono
CNR-Institute of Applied Physics "Nello Carrara", Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy. f.baldini@ifac.cnr.it.
Francesco
F
Baldini
D015374:Biosensing Techniques / Q000379:methods*; D004247:DNA / Q000032:analysis* / Q000737:chemistry; D036103:Nanotechnology / Q000379:methods*; D009693:Nucleic Acid Hybridization; D055100:Optical Fibers
D004247:DNA