Engineered peptides capable of binding to silica have been used to provide contrast in chemical force microscopy and tested for their capacity to selectively capture silica nanoparticles (NPs). Gold coated atomic force microscopy (AFM) microcantilevers with integrated tips and colloidal probes were functionalized with engineered peptides through a thiol group of a terminal cysteine which was linked via a glycine trimer to a 12-mer binding sequence. The functionalized probes demonstrated a significantly increased binding force on silicon oxide areas of a gold-patterned silicon wafer, whereas plain gold probes, and those functionalized with a random permutation of the silica binding peptide motif or an all-histidine sequence displayed similar adhesion forces to gold and silicon oxide.
View Article and Find Full Text PDFDirect polymerization of an oxaliplatin analogue was used to reproducibly generate amphiphiles in one pot, which consistently and spontaneously self-assemble into well-defined nanoparticles (NPs). Despite inefficient drug leakage in cell-free assays, the NPs were observed to be as cytotoxic as free oxaliplatin in cell culture experiments. We investigated this phenomenon by super-resolution fluorescence structured illumination microscopy (SIM) and nanoscale secondary ion mass spectrometry (NanoSIMS).
View Article and Find Full Text PDFAdherent cells respond to a wide range of substrate cues, including chemistry, topography, hydrophobicity, and surface energy. The cell-substrate interface is therefore an important design parameter in regenerative medicine and tissue engineering applications, where substrate cues are used to influence cell behavior. Thin films comprising 4.
View Article and Find Full Text PDFThe accurate characterization of submicrometer and nanometer sized particles presents a major challenge in the diverse applications envisaged for them including cosmetics, biosensors, renewable energy, and electronics. Size is one of the principal parameters for classifying particles and understanding their behavior, with other particle characteristics usually only quantifiable when size is accounted for. We present a comparative study of emerging and established techniques to size submicrometer particles, evaluating their sizing precision and relative resolution, and demonstrating the variety of physical principles upon which they are based, with the aim of developing a framework in which they can be compared.
View Article and Find Full Text PDF