Fifteen nanometer
citrate-stabilized gold nanospheres were synthesized as reported by
Turkevich et. al.69 (link) Thiolated PEG polymers
(NH2-PEG-SH) conjugated with Cy5 fluorochrome were synthesized,
followed by polymer coating of GNPs to obtain homofunctionalized fluorescently
labeled GNPs as previously reported by Rodriguez-Lorenzo et al.27 (link) To obtain hetero-GNP formulation, homofunctionalized
GNPs were coated with the second PEG coating (methoxy PEG).27 (link)GNP stability was evaluated by the optical
characterization with Cary 60 UV–vis spectrophotometer (Agilent
Technologies). Prior to measurements of GNP spectra, 20 μg/mL
of GNPs were incubated in water, PBS, complete culture medium (RPMI
1640 withl -Glutamine culture medium (Gibco) supplemented
with 10% fetal calf serum (FCS, Biowest), 1% penicillin/streptomycin,
1% sodium pyruvate, 1% nonessential amino acid (NEAA), 0.1% β-mercaptoethanol
(all from Gibco) and 15% mouse serum (obtained from mouse blood) and
incubated at 37 °C overnight. The size and ζ-potential
of GNPs were measured with Zetasizer 7.11 (Malvern) using dynamic
light scattering (DLS) and electrophoretic light scattering, respectively.
For this purpose, GNPs were diluted in water to 0.05 mg/mL.
citrate-stabilized gold nanospheres were synthesized as reported by
Turkevich et. al.69 (link) Thiolated PEG polymers
(NH2-PEG-SH) conjugated with Cy5 fluorochrome were synthesized,
followed by polymer coating of GNPs to obtain homofunctionalized fluorescently
labeled GNPs as previously reported by Rodriguez-Lorenzo et al.27 (link) To obtain hetero-GNP formulation, homofunctionalized
GNPs were coated with the second PEG coating (methoxy PEG).27 (link)GNP stability was evaluated by the optical
characterization with Cary 60 UV–vis spectrophotometer (Agilent
Technologies). Prior to measurements of GNP spectra, 20 μg/mL
of GNPs were incubated in water, PBS, complete culture medium (RPMI
1640 with
with 10% fetal calf serum (FCS, Biowest), 1% penicillin/streptomycin,
1% sodium pyruvate, 1% nonessential amino acid (NEAA), 0.1% β-mercaptoethanol
(all from Gibco) and 15% mouse serum (obtained from mouse blood) and
incubated at 37 °C overnight. The size and ζ-potential
of GNPs were measured with Zetasizer 7.11 (Malvern) using dynamic
light scattering (DLS) and electrophoretic light scattering, respectively.
For this purpose, GNPs were diluted in water to 0.05 mg/mL.