title: Quantifying ligand adsorption to nanoparticles using tandem differential mobility mass analysis.
abstract: Although electrospray-differential mobility analyzers (ES-DMA) have been previously employed to characterize ligand binding to nanoparticles, absolute quantification of surface coverage can be inaccurate at times because of ligand conformational effects. In this Letter, we report a quantitative technique by in-flight coupling of a particle mass analyzer (APM) with ES-DMA, thus enabling a direct quantitative analysis of mass independent of particle size, material, morphology and conformation. We demonstrate the utility of ES-DMA-APM by studying two model complex systems (gold nanoparticle-bovine serum albumin and polystyrene bead-antibody) as a function of concentration and pH. Our results obtained with ES-DMA-APM are in excellent agreement with prior work. We anticipate that this will enhance the capabilities of online quantitative characterization of ligand binding to nanoparticles.
authors: Suvajyoti
authors: S
authors: Guha
authors: Xiaofei
authors: X
authors: Ma
authors: Michael J
authors: MJ
authors: Tarlov
authors: Michael R
authors: MR
authors: Zachariah
mesh_terms: D000327:Adsorption; D000818:Animals; D002417:Cattle; D006046:Gold / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008024:Ligands; D053768:Metal Nanoparticles / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D012710:Serum Albumin, Bovine / Q000737:chemistry / Q000378:metabolism; D053719:Tandem Mass Spectrometry
chemical_list: D008024:Ligands; D011137:Polystyrenes; D012710:Serum Albumin, Bovine; D006046:Gold