TY - JOUR
T1 - Surface chemistry and photophysical properties of a diacetylene-peptide derivative capped quantum dots Langmuir monolayer
AU - Xu, J.
AU - Wang, C.
AU - Leblanc, R. M.
N1 - Funding Information:
This research was supported by the National Science Foundation (USA, CHE-0091390).
PY - 2009/5/1
Y1 - 2009/5/1
N2 - A diacetylene derivative, 10,12-pentacosadiynoic acid (PDA), was conjugated to a small peptide chain Cysteine-Cysteine-Glycine (CCG) through the solid-phase peptide synthesis. The (CdSe)ZnS core-shell quantum dots (QDs) capped with trioctylphosphine ligands were modified through a surface ligand reaction to prepare the PDA-CCG QDs conjugate. Both systems, PDA-CCG and PDA-CCG QDs, were investigated as Langmuir monolayer at the air-water interface through the surface pressure-area (π-A) isotherms, compression-decompression cycles, stability measurements, and in situ UV-vis and fluorescence spectroscopy. Two different π-A isotherms were observed for the systems investigated showing the importance of the peptide moiety in PDA-CCG to form a Langmuir monolayer up to a surface pressure of 50 mN m-1 compared with 15 mN m-1 for the PDA component alone. The compression-decompression cycles and stability measurements for both systems suggest the formation of a stable Langmuir monolayer over 1 h time period. Although the in situ UV-vis spectroscopy of PDAA-CCG and PDA-CCG QDs does not show an absorption spectrum, we observed by in situ fluorescence spectroscopy the photoluminescence (PL) of the PDA-CCG QDs at 560 nm, with an intensity of the PL increasing linearly with the increase of the surface pressure. Irradiating the PDA-CCG QDs Langmuir monolayer at 254 nm, we observe the photopolymerization with two distinct bands at 575 (blue band) and 630 nm (red band) of the polymer.
AB - A diacetylene derivative, 10,12-pentacosadiynoic acid (PDA), was conjugated to a small peptide chain Cysteine-Cysteine-Glycine (CCG) through the solid-phase peptide synthesis. The (CdSe)ZnS core-shell quantum dots (QDs) capped with trioctylphosphine ligands were modified through a surface ligand reaction to prepare the PDA-CCG QDs conjugate. Both systems, PDA-CCG and PDA-CCG QDs, were investigated as Langmuir monolayer at the air-water interface through the surface pressure-area (π-A) isotherms, compression-decompression cycles, stability measurements, and in situ UV-vis and fluorescence spectroscopy. Two different π-A isotherms were observed for the systems investigated showing the importance of the peptide moiety in PDA-CCG to form a Langmuir monolayer up to a surface pressure of 50 mN m-1 compared with 15 mN m-1 for the PDA component alone. The compression-decompression cycles and stability measurements for both systems suggest the formation of a stable Langmuir monolayer over 1 h time period. Although the in situ UV-vis spectroscopy of PDAA-CCG and PDA-CCG QDs does not show an absorption spectrum, we observed by in situ fluorescence spectroscopy the photoluminescence (PL) of the PDA-CCG QDs at 560 nm, with an intensity of the PL increasing linearly with the increase of the surface pressure. Irradiating the PDA-CCG QDs Langmuir monolayer at 254 nm, we observe the photopolymerization with two distinct bands at 575 (blue band) and 630 nm (red band) of the polymer.
KW - 10,12-Pentacosadiynoic acid
KW - Langmuir monolayer
KW - Photopolymerization
KW - Quantum dots
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U2 - 10.1016/j.colsurfb.2008.11.022
DO - 10.1016/j.colsurfb.2008.11.022
M3 - Article
C2 - 19185472
AN - SCOPUS:62349132347
VL - 70
SP - 163
EP - 168
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
SN - 0927-7765
IS - 2
ER -