Limits of thiol chemistry revealed by quantitative analysis of mixed layers of thiolated-PEG ligands grafted onto gold nanoparticles

Effects of polyethylene glycol on the surface of nanoparticles for targeted drug delivery

“…The peak area is proportional to the number of protons of the substance measured 64,65 . NMR has undergone improvements in equipment and processing methods and can be used to determine PEG density on the surface of NPs 66,67 . The potential problem with NMR analytical method is that particle aggregation after freezedrying results in a decrease of analyzable surface, underestimating the surface of PEG.…”

Distinct thermoresponsive behaviour of oligo- and poly-ethylene glycol protected gold nanoparticles in concentrated salt solutions

“…4,5 One of the most important parameters determining the interaction of nanoparticles with proteins is the grafting density of the EGn used to protect the surface and therefore its related chain conformation. 6 To determine de grafting density, many approximations have been reported that include nuclear magnetic resonance spectroscopy, 5,7,8 thermogravimetric analysis, 6 isothermal titration calorimetry, 9 analytical ultracentrifugation and total organic carbon analysis, 10 within others. The chain conformation of the surface-grafted polymer dictates the interfacial properties, and as described within the Alexanderde-Gennes theory, 11,12 the good solvents make the interactions with the solvent preferred over these with other polymer chains.…”

“…14 The grafting densities of EGn in AuNPs are influenced by the EGn molecular weight and the size of the nanoparticle, and are mainly responsible for the stabilization of the EGn-AuNPs in solutions of different pH, salt concentrations and temperature. 6,8 In this sense, the thermoresponsive properties of these polymers can be studied by analysing their assembly behaviour. The EGn-water system shows a phase diagram of the close-loop type with a lower critical solution temperature (LCST) at around 100 C that is mainly due to the formation of hydrogen bonds.…”

Peptide‐Conjugated Silver Nanoparticles for the Colorimetric Detection of the Oncoprotein Mdm2 in Human Serum

“…[10][11][12] Besides, their extinction coefficient is approximately three to four orders of magnitude higher than that of any organic molecule. [13,14] Gold nanoparticles (AuNPs) represent the vast majority [15] of the particles used in plasmonic nanomaterialsbased biosensors because of their well-reported synthesis, [16] ease of surface functionalization [17][18][19] and good aqueous stability. [20] Those particles have been used for the sensing of a wide variety of analytes [21] ranging from small molecules [22,23] to proteins [24][25][26][27] and nucleic acids.…”