Impact of multivalent charge presentation on peptide–nanoparticle aggregation

Abstract

SummaryStrategies to achieve controlled nanoparticle aggregation have gained much interest, due to the versatility of such systems and their applications in materials science and medicine. In this article we demonstrate that coiled-coil peptide-induced aggregation based on electrostatic interactions is highly sensitive to the length of the peptide as well as the number of presented charges. The quaternary structure of the peptide was found to play an important role in aggregation kinetics. Furthermore, we show that the presence of peptide fibers leads to well-defined nanoparticle assembly on the surface of these macrostructures.

Efficient Gene Transfection through Inhibition of β‐Sheet (Amyloid Fiber) Formation of a Short Amphiphilic Peptide by Gold Nanoparticles

“…Solutions of AuNPs ranging from 0.4 to 4.23 n m were added to a 40 μ m solution of the peptide at a neutral pH value. This resulted in a decrease in the absorbance of the pyrrole ring at λ =291 nm and an increasing absorbance of the nanoparticle plasmon band at λ =563 nm (the SPR band of the gold nanoparticles is size‐dependent: the larger the gold nanoparticle, the more red‐shifted its absorption). In addition to this, a clear isosbestic point at λ =325 nm was observed (Figure a).…”

Controlling Association and Separation of Gold Nanoparticles with Computationally Designed Zinc-Coordinating Proteins

“…Moreover, proteins can be stable in a wide array of solvent conditions and can be tuned for stability in a chosen salt and pH environment. Work has proceeded in this area by combining NPs with well-structured natural proteins to control the assembly of NPs, − develop sensors of metal ions and biological molecules, , and modulate enzymatic and biological activity. , Protein–NP systems can leverage the structures and functions of proteins to realize association of nanoparticles in one, two, and three dimensions. − Proteins adhered to nanoparticles have been used to control NP assembly via association of their unfolded states. , Electrostatic interactions involving proteins and nanoparticles have also been used to control NP association. , Specific, selective interactions involving proteins attached to nanoparticles can confer nanoparticle association, e.g., using antigen–antibody pairs , and biotin–streptavidin systems . With protein-functionalized nanoparticles, association can be controlled via variation of pH, ,, electrostatic interactions, and relative concentrations of peptides and nanoparticles .…”

“…68,69 Electrostatic interactions involving proteins and nanoparticles have also been used to control NP association. 70,71 Specific, selective interactions involving proteins attached to nanoparticles can confer nanoparticle association, e.g., using antigen−antibody pairs 72,73 and biotin−streptavidin systems. 74 With protein-functionalized nanoparticles, association can be controlled via variation of pH, 70,75,76 electrostatic interactions, 71 and relative concentrations of peptides and nanoparticles.…”

“…70,71 Specific, selective interactions involving proteins attached to nanoparticles can confer nanoparticle association, e.g., using antigen−antibody pairs 72,73 and biotin−streptavidin systems. 74 With protein-functionalized nanoparticles, association can be controlled via variation of pH, 70,75,76 electrostatic interactions, 71 and relative concentrations of peptides and nanoparticles. 77 Protein−protein interactions offer great promise for tunable association of protein−NP systems.…”

Efficient Gene Transfection through Inhibition of β‐Sheet (Amyloid Fiber) Formation of a Short Amphiphilic Peptide by Gold Nanoparticles

“…As ac onsequence of the high positive zeta potential of peptide 1 (z =+38 mV,T able S2), we expected that 1 will interact with the negatively charged citrate-stabilized AuNPs (z = À35 mV,T able S2) through electrostatic interactions (Scheme 1). UV/Vis absorption spectroscopy was applied to monitor the interaction of the AuNPs with peptide 1.S olutions of AuNPs ranging from 0.4 to 4.23 nm were added to a4 0mm solution of the peptide at an eutral pH value.T his resulted in ad ecrease in the absorbance of the pyrrole ring at l = 291 nm and an increasing absorbance of the nanoparticle plasmon band at l = 563 nm (the SPR band of the gold nanoparticles is sizedependent:t he larger the gold nanoparticle,t he more redshifted its absorption [18] ). In addition to this,aclear isosbestic point at l = 325 nm was observed (Figure 1a).…”