1. 2007 65 Vol. 65, 2007
5 , 445 450 ACTA CHIMICA SINICA No. 5, 445 450
· ·
*
( 730000)
(PAMAM) ,
. . , ,
(G0F) , , (G1F) (G2F) .
,
. .
; ; ; ; ;
Excimer and Ground-state Complex Formation of Fluorescein in a
Dendrimer Based on Silica Nanoparticles
DENG, Jian SU, Zhi-Xing*
(College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou 730000)
Abstract Polyamidoamine dendrimers based on silica nanoparticles have been prepared, then the fluo-
rescein was bonded onto the surface of such dendrimers. The photophysical behavior of different generations
was studied carefully by using fluorescence spectroscopy in solid state, aqueous suspension or acetone sus-
pension. An excimer fluorescent emission was observed for the lowest generation (G0F), and fluo-
rescein-fluorescein complex fluorescent emissions were observed for the first generation (G1F) and the sec-
ond-generation (G2F). The different photophysical behaviors in various suspension indicated that the hy-
drogen-bonding interaction was crucial to form either excimer or fluorescein-fluorescein complex. These
results will be important and beneficial for design and development of this system used as a core-shell fluo-
rescent sensor of nanosilica.
Keywords fluorescein; silica nanoparticle; hydrogen bonding; excimer; ground-state complex; fluorescent
sensor
10 , , ,
, .
, ,
[1 3]
. ,
, ,
* E-mail: suzx@lzu.edu.cn
Received April 4, 2005; revised June 5, 2006; accepted October 21, 2006.

2. 446 Vol. 65, 2007
. 1.2
[4]
Trarek 1.2.1
, (G0) (G1) (G2)
[5]
[10], Scheme 1a .
: , 1.2.2 G0F, G1F G2F
; ;
0. 100 g N2 THF (20 mL)
.
, DCC (0.25 g), DMAP
[4,6,7]
G0 (0. 200 g). N2 20 h. ,
[8,9]
,
, .
.
, THF 24 h DCC
, G0F.
,
Scheme 1b, Schemes 2, 3.
,
G1F G2F G0F ,
Scheme 2.
.
1.2.3
G0F, G1F G2F
1
, ,
1.1 ( , 7 d ),
.
(FL, , ).
5 mg/mL.
(NS, ),
640 m2/g 10 nm, 110 1.3
48 h. γ- (APS, , Nicolet NEXUS 670
). (MA) (EDA) .X (XPS) PHI5702
(THF) , , . 4- , AlKαX .
(DMAP, Alfa , ). N,N- F-4500 FL ,
(DCC, , ).
Scheme 1

3. No. 5 447
2.5 nm, [13] , N
a.u. 400.20 eV, N ,
N G0F N
2 . , G0F N 400.52 eV,
. G1F G2F , N
γ- . , G0F, G1F G2F N ,
(G0) (NS) , G0 NS . Balbuena[14]
, (2978, 2933 , PAMAM ,
1 1
cm ), (1470 cm ), (736 :
cm 1); (1522 cm 1)
(697 cm 1). NS G0, (970 ;
cm 1) , NS [11]
. . , N
Schemes 2, 3 , .
. XPS 2 G0F, G1F G2F ,
. G0 , 493 nm. G0F (520
[12]
: . , 1a , nm) (546 nm),
399.55 401.73 eV [15]
; G1F G2F
[12]
N . G0F , G0F , (546 nm ). 3 , G1F G2F
G0. 1b , 399.20 401.80 eV G0 G0F , G1F
N ; 400.52 eV G2F
[13]
N . 1c , 398.85, 399.87 401.56 , G1F G2F
eV G1F N . [16]
.
1d , 398.86, 399.82 401.58 eV G2F
N .
Scheme 2

4. 448 Vol. 65, 2007
Scheme 3
[8]
,
[17]
, Truis , , , .
, , G0F, G1F
. G2F .

5. No. 5 449
2 G0F, G1F G2F (
493 nm)
Figure 2 Fluorescence emission spectra of solid G0F, G1 and
G2F
3 G0F, G1F G2F (
546 nm)
Figure 3 Fluorescence excitation spectra of solid G0F, G1 and
G2F
. , G0F G1F
520 nm, G2F 538 nm( 5).
G2F 2 546 nm
, G2F
1 G0, G0F, G1F G2F . G2F G0F G1F
Figure 1 XPS of G0, G0F, G1 and G2F
, G2F G0F
G1F . ,
,
G2F ,
, G0F,
, G0F G1F
G1F G2F .
, .
24.0 9.66,
,
, G0F, G1F G2F ,
.
. , G0F, G1F G2F
, G0F, G1F G2F ,
520 nm ( 4),
,
.
.
, ,
, ,
,

6. 450 Vol. 65, 2007
.
.
,
.
References
1 Mirkin, C. A.; Letsinber, R. L.; Mucic, R. C.; Storhoff, J. J.
Nature 1996, 382, 607.
2 Montalti, M.; Prodi, L.; Zaccheroni, N.; Falini, G. J. Am.
4 G0F, G1F G2F ( Chem. Soc. 2002, 124, 13540.
493 nm) 3 Caruso, F. Adv. Mater. 2001, 13, 11.
Figure 4 Fluorescence emission spectra of G0, G0F, G1 and 4 Trarek, H.; Chaddar, J. K. J. Phys. Chem. B 2001, 105,
8729.
G2F in aqueous suspension
5 Bosman, A. W.; Janssen, H. M.; Meijer, E. W. Chem. Rev.
1999, 99, 1665.
6 Kwon, T. W.; Alam, M. M.; Jenekhe, S. A. Chem. Mater.
2004, 16, 4657.
7 Stewart, G. M; Fox, M. A. Chem. Mater. 1998, 10, 960.
8 Wang, H.; Zhang, X. H.; Wu, S. K. Acta Chim. Sinica 2003,
61, 1921 (in Chinese).
( , , , , 2003, 61, 1921.)
9 Wang, H.; Zhang, X. J.; Zhang, X. H.; Wu, S. K. Acta Phys.
Chim. Sin. 2004, 20(3), 313 (in Chinese).
( , , , , , 2004,
20(3), 313.)
10 Liu, P.; Tian, J.; Liu, W. M.; Xue, Q. J. Chin. J. Chem.
2003, 21, 960.
5 G0F, G1F G2F ( 11 Yin, W.; Zhang, M. S. J. Alloys Comp. 2003, 1 2, 231.
493 nm) 12 Gu, R. A.; Liu, G. K. Acta Chim. Sinica 2003, 61, 1550 (in
Figure 5 Fluorescence emission spectra of G0F, G1F and G2F Chinese).
( , , , 2003, 61, 1550.)
in acetone suspension
13 Hendrickson, D. N.; Hollonder, J. M.; Jolly, W. L. Inorg.
[15] Chem. 1969, 8, 2642.
,
14 Vasquez, F. T.; Balbuena, P. J. Phys. Chem. 2004, 108,
. 15982.
, 15 Li, S. J.; Ji, C. G. Theories and Application of Polymeric
[18]
, , Photochemistry, Fudan University Press, Shanghai, 1993, p.
54 (in Chinese).
. G1F G2F
( , , ,
(Scheme 2), , , , 1993, p. 54.)
G0F, , 16 Li, S. J.; Ji, C. G. Theories and Application of Polymeric
, Photochemistry, Fudan University Press, Shanghai, 1993, p.
58 (in Chinese).
, .
( , ,
, , 1993, p. 58.)
3 17 Truis, S. P.; Dewar, P. J.; MacGllivary, T. F.; Gispo, S. M.
J. Colloid Interface Sci. 2000, 228, 253.
18 Tasuku, U.; Yasuteru, U.; Ken-ichi, S.; Hideo, T.; Hitotatsu,
K.; Kazuya, K.; Kei, O.; Shunichi, F.; Tetsuo, N. J. Am.
,
Chem. Soc. 2004, 126, 14079.
, , ;
(A0504041 QIN, X. Q.; LING, J.)