Photoluminescence intensity enhancement in SWNT aqueous suspensions due to reducing agent doping: Influence of adsorbed biopolymer

• Published in: Chemical physics 2014-06, Vol.438, p.23-30
• Main Authors: Kurnosov, N.V., Leontiev, V.S., Linnik, A.S., Lytvyn, O.S., Karachevtsev, V.A.
• Format: Article
• Language: English
• Subjects: Carbon nanotubes; Exciton; Luminescence; Nanobiohybrid; Quantum yield; Reducing agent
• ISSN: 0301-0104
• DOI: 10.1016/j.chemphys.2014.04.006

[Display omitted] •Dithiothreitol enhances the carbon nanotube emission covered by native biopolymers.•The amount of emission enhancement from nanotube depends on adsorbed biopolymer type.•The ordered polymer weakens the dithiothreitol doping effect on the nanotube emission.•Homopolynucleotide polyC shows more ordering on nanotube than native biopolymers.•Reducing agent addition can provide an indirect probing of nanotube surface coverage. The influence of biopolymer wrapped around nanotube on the enhancement of the semiconducting single-walled carbon nanotube (SWNT) photoluminescence (PL) in aqueous suspension which increases due to the reducing agent dithiothreitol (DTT) doping effect was revealed. The greatest enhancement of PL was observed for SWNTs covered with double- or single stranded DNA (above 170%) and DTT weak influence was revealed for SWNTs:polyC suspension (∼45%). The magnitude of the PL enhancement depends also on nanotube chirality and sample aging. The behavior of PL from SWNTs covered with various polymers is explained by the different biopolymers ordering on the nanotube surface. The ordered polymer conformation on the nanotube weakens the reducing agent doping effect. The method of reducing agent doping of nanotube:biopolymer aqueous suspension can serve as a sensitive luminescent probe of the biopolymer ordering on the carbon nanotube and can be used to increase the sensitivity of luminescent biosensors.