Efficient preparation of size tunable PEGylated gold nanoparticles

Abstract

A facile, one-step self-assembly of polymer nanoreactors is reported for the fabrication of uniform PEGylated gold nanoparticles. Nanoreactor assembly occurs within milliseconds and gold nanoparticles are produced within minutes at room temperature. The presented approach enables continuous synthesis of size tunable gold nanoparticles with tailorable surface chemistry. Figure 2. (a) Initial nanoreactor size distributions measured by DLS and (b) UV absorbance of the dialyzed dispersions synthesized at a range of pHs by diluting the effluent from the mixer into PBS, pH 7.4, water (MQ) or 0.01M HCl.The nanoreactor assembly occurs on the order of milliseconds (time scale of mixing). The reduction to Au(0) occurs in the nanoreactor where TA is localized. The reduction is evident by the transition from the light amber dispersion to strongly red or purple colored dispersions associated with colloidal gold (Fig. 2, Supporting Information Figure S2) that occurs within ~20 seconds (at pH 6) to ~7 minutes (pH 2). The effect of pH on the rate of reduction has been used to tune nanoparticle size over a relatively narrow range 17-20 nm 20 . We demonstrate this strategy

Rapid Self-Assembly of Metal/Polymer Nanocomposite Particles as Nanoreactors and Their Kinetic Characterization

“…The majority of the gold nanoparticles appear to be in the nanoreactor core, although multiple polymer layers are not visible on TEM due to low electron density. This result is consistent with previous reports of encapsulated gold nanoparticles via Flash NanoPrecipitation (FNP) [21,35]. Based on TEM, some of the gold may also be associated with the PEG-layer of the nanoreactors whereas unassociated gold would be expected to precipitate out of the dispersion as well as affect the size distribution measured by DLS.…”

Rapid Self-Assembly of Polymer Nanoparticles for Synergistic Codelivery of Paclitaxel and Lapatinib via Flash NanoPrecipitation

“…The dispersions appeared red which is consistent with the tris-complex of TA and iron expected at pH 7.4 [31,39]. Nanoparticles encapsulating the TA-Fe complex (TA-Fe NPs) are 109 ± 5 nm ( Figure S2) with a zeta potential of -21.4 ± 2.1 mV consistent with other PEGylated nanoparticles [33,40].…”

Single-Step Self-Assembly and Physical Crosslinking of PEGylated Chitosan Nanoparticles by Tannic Acid

“…The zeta potential of the resulting nanoparticle dispersion was +16 ± 4 mV, which is lower than typically reported for chitosan particles (~+50 mV) [24,25]. This result also suggests that the nanoparticles were to some degree sterically stabilized by the block copolymer as zeta potentials greater than +35 mV are required for fully electrostatic colloidal stabilization [21].…”

“…Nanoparticle assembly was performed using a confined impinging jet mixer with dilution as previously described [20,21]. Under hand operation with 1 mL syringes, mixing Reynold’s numbers of 1300 were achieved [15,22].…”