title: A high yield, one-pot dialysis-based process for self-assembly of near infrared absorbing gold nanoparticles.
abstract: OBJECTIVE
  A facile, dialysis-based synthesis of stable near infrared (nIR) absorbing plasmonic gold nanoparticles (λmax=650-1000 nm) will increase the yield of nIR particles and reduce the amount of gold colloid contaminant in the product mixture.
  
  
  METHODS
  Chloroauric acid and sodium thiosulfate were reacted using a dialysis membrane as a reaction vessel. Product yield and composition was determined and compared to traditional synthesis methods. The product particle distribution, yield, and partitioning of gold between dispersed product and membrane-adsorbed gold were determined.
  
  
  RESULTS
  The synthesis results in polydisperse particle suspensions comprised of 70% spheroid-like particles, 27% triangular plates, and 3% rod-like structures with a 3% batch-to-batch variation and a prominent nIR absorption band with λmax=650-1000 nm. The amount of small gold colloid (λmax=530 nm; d<10 nm) in the isolated product was reduced by 96% compared to traditional methods. Additionally, 91.1% of the gold starting material is retained in the solution-based nanoparticle mixture while 8.2% is found on the dialysis membrane. The synthesis results in a quality ratio (QR=Abs(nIR)/Abs(530)) of 1.7-2.4 (twice that of previous techniques) and 14.3 times greater OD∗ml yield of the nIR-absorbing nanoparticle fraction.
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: dnpatel01@gmail.com.
authors.forename: Dhruvinkumar
authors.initials: D
authors.lastname: Patel
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: kurtis.james@louisville.edu.
authors.forename: Kurtis T
authors.initials: KT
authors.lastname: James
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: martin.otoole@louisville.edu.
authors.forename: Martin
authors.initials: M
authors.lastname: O'Toole
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: guandongzhang@hotmail.com.
authors.forename: Guandong
authors.initials: G
authors.lastname: Zhang
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: rob.keynton@louisville.edu.
authors.forename: Robert S
authors.initials: RS
authors.lastname: Keynton
authors.affiliation: Department of Bioengineering, University of Louisville, Louisville, KY 40292, United States. Electronic address: iamgobin@gmail.com.
authors.forename: André M
authors.initials: AM
authors.lastname: Gobin
mesh_terms: D003102:Colloids / Q000737:chemistry; D003956:Dialysis; D006046:Gold / Q000737:chemistry*; D007259:Infrared Rays; D008567:Membranes, Artificial; D053768:Metal Nanoparticles / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D013499:Surface Properties
chemical_list: D003102:Colloids; D008567:Membranes, Artificial; D006046:Gold
keywords: Coating; DiaSynth; Dialysis; Gold nanoparticles; Near infrared; Synthesis