2 research outputs found
Activatable cell–biomaterial interfacing with photo-caged peptides
Spatio-temporally tailoring cell–material interactions is essential for developing smart delivery systems and
intelligent biointerfaces. Here we report new photo-activatable cell–material interfacing systems that
trigger cellular uptake of various cargoes and cell adhesion towards surfaces. To achieve this, we
designed a novel photo-caged peptide which undergoes a structural transition from an antifouling ligand
to a cell-penetrating peptide upon photo-irradiation. When the peptide is conjugated to ligands of
interest, we demonstrate the photo-activated cellular uptake of a wide range of cargoes, including
small fluorophores, proteins, inorganic (e.g., quantum dots and gold nanostars) and organic
nanomaterials (e.g., polymeric particles), and liposomes. Using this system, we can remotely regulate
drug administration into cancer cells by functionalizing camptothecin-loaded polymeric nanoparticles
with our synthetic peptide ligands. Furthermore, we show light-controlled cell adhesion on a peptidemodified surface and 3D spatiotemporal control over cellular uptake of nanoparticles using two-photon
excitation. We anticipate that the innovative approach proposed in this work will help to establish new
stimuli-responsive delivery systems and biomaterials
Quantitative volumetric Raman imaging of three dimensional cell cultures
The ability to simultaneously image multiple biomolecules in biologically relevant
three-dimensional (3D) cell culture environments would contribute greatly to the understanding of complex cellular mechanisms and cell–material interactions. Here, we present a
computational framework for label-free quantitative volumetric Raman imaging (qVRI). We
apply qVRI to a selection of biological systems: human pluripotent stem cells with their
cardiac derivatives, monocytes and monocyte-derived macrophages in conventional cell
culture systems and mesenchymal stem cells inside biomimetic hydrogels that supplied a 3D
cell culture environment. We demonstrate visualization and quantification of fine details in
cell shape, cytoplasm, nucleus, lipid bodies and cytoskeletal structures in 3D with unprecedented biomolecular specificity for vibrational microspectroscopy