at room temperature. The reaction solution was transferred to a
centrifuge tube and hexanes were added until the mixture
became cloudy. The reaction mixture was then centrifuged at
5000 rpm for 10 min and the supernatant was discarded. The
precipitated nanoparticles were then redispersed in 5 mL of
DMSO (3.8 wt%) for further experiments. FTIR (cm−1): 2935,
2879, 2110 (strong, N3), 1660, 1252, 1140, 1070, 920.
2940, 2362, 2110 (weak, N3), 1654, 1515, 1251, 1114, 1056,
989, 824.
Acknowledgements
This research was supported by the Natural Sciences and Engi-
neering Research Council (NSERC) of Canada, the Canada
Research Chairs Program, and Simon Fraser University through
funding from the Community Trust Endowment Fund. This
work made use of 4D LABS shared facilities supported by the
Canada Foundation for Innovation (CFI), British Columbia
Knowledge Development Fund (BCKDF) and Simon Fraser
University. J.-C. Boyer thanks the Michael Smith Foundation for
Health Research for support. C.-J. Carling thanks Simon Fraser
University for a Graduate Fellowship.
Synthesis of 2-component systems 1a-NP and 1b-NP. A sol-
ution of compound 3a (3.47 mL of a stock solution of 6.0 mg,
0.01 mmol, 3.0 × 10−3 M in CH3CN) or 3b (3.83 mL of a stock
solution of 5.2 mg, 0.01 mmol, 2.7 × 10−3 M in CH3CN) was
added to a 20 mL scintillation vial and the solvent was removed
under reduced pressure. A dispersion of the azide nanoparticles
a-NP (0.5 mL, 3.8 wt% in DMSO) was added to the vial and the
mixture sonicated. The resulting clear dispersion was transferred
to a 3 mL vial equipped with a stir-bar. Freshly prepared
CuSO4·5H2O (24 μL, 1.04 × 10−4 mmol, 4.41 × 10−3 M in
H2O), sodium L-ascorbate (18 μL, 1.04 × 10−3 mmol, 5.75 ×
10−2 M in H2O), H2O (8 μL) and Et3N (10 μL) were added via
calibrated auto-pipette and the reaction vessel was sealed and
stirred at 35 °C for 24 h. The reaction mixture was transferred to
a 1.5 mL Eppendorf tube and diluted with absolute EtOH
(1 mL). After centrifugation (13 500 rpm, 30 min) the super-
natant was discarded and the pellet redispersed in THF (1 mL)
or CH2Cl2 (1 mL) for 3a and 3b, respectively, and centrifuged
(13 500 rpm, 20 min). The supernatant was discarded and the
pellet was redispersed in suitable solvent (2 mL), the clear col-
loidal dispersions (1a-NP: 3 wt% in THF, 1b-NP: 2 wt% in
CH2Cl2) were used for subsequent experiments without any
further purification. Loading: 1a-NP: 5000–7000 molecules per
nanoparticle, 1b-NP: 6000–8000 molecules per particle (Tables
S1–S3‡). FTIR (cm−1): 1a-NP: 2964, 2928, 2855, 2360, 2110
(weak, N3), 1655, 1515 (s), 1274, 1101, 1056, 988, 822. 1b-NP:
2956, 2928, 2839, 2364, 2110 (weak, N3), 1656, 1511, 1252,
1100, 1070, 1035, 824.
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Synthesis of mixed 3-component system 1ab-NP. A mixture of
compounds 3a (1.73 mL of a stock solution of 3.0 mg,
0.005 mmol, 3.01 × 10−3 M in CH3CN) and 3b (1.92 mL of a
stock solution of 2.6 mg, 0.005 mmol, 2.72 × 10−3 M in
CH3CN) was added to a 20 mL scintillation vial and the solvent
was removed under reduced pressure. A dispersion of the azide
nanoparticles a-NP (0.5 mL, 3.8 wt% in DMSO) was added, the
mixture sonicated and the resulting clear dispersion was trans-
ferred to a 3 mL vial equipped with a stir-bar. Freshly prepared
CuSO4·5H2O (11 μL, 1.0 × 10−4 mmol, 9.4 × 10−3 M in H2O),
sodium L-ascorbate (28 μL, 1.0 × 10−3 mmol, 3.79 × 10−2 M in
H2O), H2O (11 μL) and Et3N (10 μl) were added via auto-
pipette and the reaction vessel was sealed and stirred at 35 °C for
24 h. The reaction mixture was transferred to a 1.5 mL Eppen-
dorf tube and diluted with absolute EtOH (1 mL). After centrifu-
gation (13 500 rpm, 30 min) the supernatant was discarded and
the pellet redispersed in THF (1 mL) and centrifuged (13 500
rpm, 20 min). The supernatant was discarded and the pellet was
redispersed in THF (2 mL). The slightly hazy colloidal dis-
persion (2 wt%) was used for subsequent experiments without
any further purification. FTIR (cm−1): 1ab-NP 2959, 2997,
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