Light-Responsive Janus-Particle-Based Coatings for Cell Capture and Release

Abstract

A robust light-responsive coating based on Janus composite particles is achieved. First, strawberry-like silica Janus particles are synthesized by the sol−gel process at a patchy emulsion interface. One side of the silica Janus particles possesses nanoscale roughness, and the other side is flat. Then, spiropyran-containing polymer brushes are grafted onto the coarse hemispherical side of the as-synthesized Janus particles, and the other flat side is modified with imidazoline groups. The light-responsive polymer brush-terminated coarse hemispherical sides direct toward the air when the Janus composite particles self-organize into a layer on the surface of epoxy resin substrate. The imidazoline groups react with the epoxy groups in the epoxy resin to form a robust smart coating. The coating can be reversibly triggered between hydrophobic and hydrophilic by UV and visible-light irradiation, which is attributed to the isomerization of spiropyran moieties. When the hydrophobic ring-closed spiropyran form is prominent, HeLa cells can be effectively captured onto the coating. After UV light irradiation, the ring-closed spiropyran form changes to the hydrophilic ring-opened zwitterionic merocyanine form, and then the captured cells are released. This work shows promising potential for engineering advanced smart biointerfaces.

Sorption Characteristics of Polymer Brushes in Equilibrium with Solvent Vapors

“… 1 Such brushes have many uses. 2 For example, they have been proven to be effective lubricants, 3 , 4 smart adhesives, 5 , 6 and sensitive sensors. 7 , 8 For these applications, the brushes are typically completely immersed in a solvent.…”

Mechanochromophore‐Linked Polymeric Materials with Visible Color Changes

“…SP is a highly hydrophobic molecule, whereas MC is more hydrophilic, enabling them to be used in the fields of self-assembly, [47,48] drug delivery, [49,50] and wettability control and cell adhesion. [51,52] The increase in molecular size during the transition from SP to MC has been used for microfluidic applications. [53,54] The transition from a neutral to charged molecule has been applied for metal ion detection [55,56] and electrochemistry.…”

Stimuli-Responsive Materials for Tissue Engineering and Drug Delivery

“…Polymers and hydrogels have been widely used as biomaterials for the fabrication of medical devices and tissue engineering scaffolds [117,118], as they provide biocompatibility, biodegradability, mechanical properties, hydrophobicity, and crystallinity that are crucial to allow tissue growth. An interesting material was developed by coating strawberry-like silica Janus particles with spiropyran-containing polymer brushes for controlling cell capture and release by UV and visible-light irradiation [119]. This hydrophobic coating showed high efficiency to cell capture due to the specific interaction between the hydrophobic ring-closed of spiropyran form and cell surface fibronectin protein [120].…”