Noncovalent functionalization of carbon nanotubes by fluorescent polypeptides: supramolecular conjugates with pH-dependent absorbance and fluorescence.
Fluorescent cut single-walled carbon nanotube (CSWCNT) were prepared by simply mixing CSWCNT with water soluble rhodamine 6G (Rh6G) conjugated poly(3,4-dihydroxyphenylalanine) and poly(L-tyrosine) to form highly stable product with good dispersity in buffer solution. The optical absorbance and fluorescence spectra of the resulting fluorescent CSWCNT display interesting pH-dependent optical properties, emitting strong fluorescence only in acidic environment. Considering the extracellular pH of tumor tissue is acidic, the pH-sensitive conjugates have advantages to sense tumor cells selectively, enabling it to be utilized as a biosensor for detecting cancer cells. The protocol employed to functionalize the CSWCNT with Rh6G conjugated polypeptides in aqueous solution is proven to be direct, fast and easily scalable.
WCU Centre for Synthetic Polymer Bioconjugate Hybrid Materials, Department of Polymer Science and Engineering, Pusan National University, Pusan 609-735, Korea.
Xin Hua
XH
Huang
Renjith P
RP
Johnson
Song I
SI
Song
Il
I
Kim
D000042:Absorption; D015374:Biosensing Techniques / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D037742:Nanotubes, Carbon / Q000737:chemistry*; D010316:Particle Size; D010455:Peptides / Q000737:chemistry*; D012235:Rhodamines / Q000032:analysis* / Q000737:chemistry*; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013499:Surface Properties
D046911:Macromolecular Substances; D037742:Nanotubes, Carbon; D010455:Peptides; D012235:Rhodamines; C026188:rhodamine 6G