Publications by authors named "Behzad Tangeysh"

Introducing engineered nanoparticles (NPs) into a biofluid such as blood plasma leads to the formation of a selective and reproducible protein corona at the particle-protein interface, driven by the relationship between protein-NP affinity and protein abundance. This enables scalable systems that leverage protein-nano interactions to overcome current limitations of deep plasma proteomics in large cohorts. Here the importance of the protein to NP-surface ratio (P/NP) is demonstrated and protein corona formation dynamics are modeled, which determine the competition between proteins for binding.

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SignificanceDeep profiling of the plasma proteome at scale has been a challenge for traditional approaches. We achieve superior performance across the dimensions of precision, depth, and throughput using a panel of surface-functionalized superparamagnetic nanoparticles in comparison to conventional workflows for deep proteomics interrogation. Our automated workflow leverages competitive nanoparticle-protein binding equilibria that quantitatively compress the large dynamic range of proteomes to an accessible scale.

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Large-scale, unbiased proteomics studies are constrained by the complexity of the plasma proteome. Here we report a highly parallel protein quantitation platform integrating nanoparticle (NP) protein coronas with liquid chromatography-mass spectrometry for efficient proteomic profiling. A protein corona is a protein layer adsorbed onto NPs upon contact with biofluids.

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Irradiation studies of acetonitrile solutions of copper(II) acetate dimer ([Cu(OAc)]) using high energy, simultaneously spatially and temporally focused (SSTF) ultrashort laser pulses are reported. Under ambient conditions, irradiation for relatively short periods of time (10-20 s) selectively produces relatively small, narrowly size-dispersed (3.5 ± 0.

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Femtosecond laser irradiation of aqueous KAuCl followed by postirradiation reduction with hydrogen peroxide (HO) is investigated as a new approach for the synthesis of gold nanotriangles (AuNTs) without any added surfactant molecules. Laser irradiation was applied for times ranging from 5 to 240 s, and postirradiation reduction of the solutions was monitored by UV-vis spectroscopy. Laser processing of aqueous KAuCl for 240 s, where the full reduction of Au(III) occurred during irradiation, produced spherical gold nanoparticles (AuNPs) with an average size of 11.

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Direct, multiphoton photolysis of aqueous metal complexes is found to play an important role in the formation of nanoparticles in solution by ultrafast laser irradiation. In situ absorption spectroscopy of aqueous [AuCl4](-) reveals two mechanisms of Au(0) nucleation: (1) direct multiphoton photolysis of [AuCl4](-) and (2) radical-mediated reduction of [AuCl4](-) upon multiphoton photolysis of water. Measurement of the reaction kinetics as a function of solution pH reveals zeroth-, first-, and second-order components.

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The synthesis of surfactant-free Au nanoplates is desirable for the development of biocompatible therapeutics/diagnostics. Rapid Δ-function energy deposition by irradiation of aqueous KAuCl4 solution with a 5 s burst of intense shaped laser pulses, followed by slow addition of H2O2, results in selective formation of nanoplates with no additional reagents. The primary mechanism of nanoplate formation is found to be oriented attachment of the spherical seeds, which self-recrystallize to form crystalline Au nanoplates.

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Reduction of Cu(II) cations immobilized as cross-linkers in polyacrylate network colloids produce relatively small (~3 nm) Cu metal particles which are further tuned to smaller size (~1.5 nm) by partially substituting Ca(+2) for Cu(+2) in the polymer network colloid.

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The mean diameter of palladium metal particles produced by citrate reduction of the (H(+))(n) PDMAEMA/[PdCl(4)](2-) aqueous system increases from 1.4 nm to 5.0 nm as the pH decreases from 6.

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Diprotonic sulfuric and succinic acids react efficiently with the tertiary amine sites in polydimethylaminoethylmethacrylate (PDMAEMA) to produce polymer colloid nano-particles held together by dinegatively charged anions that cross link the partially protonated PDMAEMA homopolymer. This procedure is used to encorporate [PtCl(6)](2-) as a cross linker into the framework of well defined polymer network colloid particles that have dual roles as nanoreactors and a source of protective polymer coating. Reduction of the cross linking [PtCl(6)](2-) groups produces platinum metal nano-particles (1.

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