PMID- 25321883
OWN - NLM
STAT- PubMed-not-MEDLINE
DCOM- 20150521
LR  - 20141113
IS  - 1474-9092 (Electronic)
IS  - 1474-905X (Linking)
VI  - 13
IP  - 12
DP  - 2014 Dec
TI  - Elucidation of photophysical changes and orientation of acridine orange dye on 
      the surface of borate capped gold nanoparticles using multi-spectroscopic 
      techniques.
PG  - 1741-52
LID - 10.1039/c4pp00223g [doi]
AB  - In the present work, we have carried out a detailed investigation on the binding 
      interaction of acridine orange (AO) with borate capped gold nanoparticles (Au 
      NPs) by absorption spectroscopy, steady state emission spectroscopy, time 
      resolved fluorescence spectroscopy, high resolution transmission electron 
      microscopy (HR-TEM), dynamic light scattering (DLS), zeta potential measurements, 
      Fourier transform infrared (FT-IR) and Raman spectroscopy. The phenomena of 
      hypochromism and the appearance of coupled localized surface plasmon resonance 
      (LSPR) bands in the absorption spectral studies of the AO-Au NP system suggested 
      the vital role of electrostatic interactions between AO dye and Au NPs. The 
      results from HR-TEM and DLS measurements confirmed the formation of aggregated 
      clusters of nanoparticles. The zeta potential studies of Au NPs and AO coated Au 
      NPs suggested the occurrence of partial surface charge neutralization of 
      negatively charged Au NPs by cationic AO dye. The interparticle edge to edge 
      separation distance of adjacent Au NPs revealed the presence of AO molecules 
      between the nano-gaps of Au NPs. Emission spectral studies of AO in the presence 
      of increasing concentrations of Au NPs indicated the existence of a static 
      quenching mechanism. Time resolved fluorescence spectroscopic study further 
      validated the findings of steady state emission measurements. The comparison of 
      experimental emission quenching data with the theoretically calculated value 
      suggested the probable multi-layered assembly of AO on the surface of Au NPs. 
      FT-IR and Raman spectral studies further revealed the existence of electrostatic 
      interactions and possible horizontal orientation of AO dye molecules on Au NP 
      surfaces.
FAU - Selva Sharma, Arumugam
AU  - Selva Sharma A
AD  - Department of Chemistry, Bharathiar University, Coimbatore - 641046, India. 
      chelian73@yahoo.com.
FAU - Ilanchelian, Malaichamy
AU  - Ilanchelian M
LA  - eng
PT  - Journal Article
DEP - 20141016
PL  - England
TA  - Photochem Photobiol Sci
JT  - Photochemical & photobiological sciences : Official journal of the European 
      Photochemistry Association and the European Society for Photobiology
JID - 101124451
EDAT- 2014/10/17 06:00
MHDA- 2014/10/17 06:01
CRDT- 2014/10/17 06:00
PHST- 2014/10/17 06:00 [entrez]
PHST- 2014/10/17 06:00 [pubmed]
PHST- 2014/10/17 06:01 [medline]
AID - 10.1039/c4pp00223g [doi]
PST - ppublish
SO  - Photochem Photobiol Sci. 2014 Dec;13(12):1741-52. doi: 10.1039/c4pp00223g. Epub 
      2014 Oct 16.