Sunghwan Kim

Abstract Epidermal electronic systems for detecting electrophysiological signals, sensing, therapy, and drug delivery are at the frontier in man–machine interfacing for healthcare. However, it is still a challenge to develop multifunctional bioapplications with minimal invasiveness, biocompatibility, and stable electrical performance under various mechanical deformations of biological tissues. In this study, a natural silk protein with carbon nanotubes (CNTs) is utilized to realize an epidermal

Abstract Triboelectric electronic skins (E‐skins) can be used as primary interactive devices for human–machine interfaces (HMIs). However, devices for seamless on‐skin operations must be soft and deformable, and attachable to and compatible with the skin. In this paper, a substrate‐free, skin‐compatible, skin‐attachable, mechanically deformable, and self‐powered E‐tattoo sticker consisting of carbon nanotubes (CNTs) and silk nanofibers (SNFs) is presented. The E‐tattoo can be imperceptibly tatto

Novel concepts for manipulating plasmonic resonances and the biocompatibility of plasmonic devices offer great potential in versatile applications involving real-time and in vivo monitoring of analytes with high sensitivity in biomedical and biological research. Here we report a biocompatible and highly tunable plasmonic bio/chemical sensor consisting of a natural silk protein and a gold nanostructure. Our silk plasmonic absorber sensor (SPAS) takes advantage of the strong local field enhancemen

Significance Although many researchers show interest in biopolymers such as proteins and DNA due to their favorable material traits, applying biopolymer-based nanooptics to biological tissues is still challenging due to large deformation and humid environments of tissues. This constraint requires that the nanooptical devices must hold deformability, durability, and biocompatibility at the same time. In this study, we report deformable and conformal silk hydrogel inverse opals that may lead to gi

New types of air filter technologies are being called because air pollution by particulate matters (PMs) and volatile organic compounds has raised serious concerns for public health. Conventional air filters have limited application and poor degradability and they become non-disposable wastes after use. Here, we report a highly efficient, eco-friendly, translucent, and multifunctional air purification filter that is highly effective for reducing air pollution, protecting the environment, and det

Responsive optical resonators are used in chemical and biological sensing applications because their optical properties can be tuned by interactions with their environment. The use of non-nanostructured designs and biological materials expands the applications of these resonators because of their biocompatibility and low cost. Natural silk protein enables designing cost-effective, biocompatible, and chemically tunable metal–insulator–metal (MIM) resonators for color filters and superabsorbers. O

A fully biocompatible laser would be attractive in many aspects of biomedical research. Here we report a single-mode biocompatible distributed feedback laser consisting of silk, riboflavin and silver in the form of a freestanding film. The distributed feedback structure has a large surface area and flexibility. The fabricated laser exhibited single-mode lasing at a wavelength of 495 nm.

Abstract Biodegradable and physically transient optics represent an emerging paradigm in healthcare devices by harnessing optically active system and obviating issues with chronic uses. Light emitting components that can efficiently interact with their environments have advantages of high sensitivity, visibility, and wireless operation. Here, we report a novel combination of silk biopolymer and optically active organic dyes resulting in versatile fluorescent silk nanofibers (FSNs). FSNs generate

We demonstrated biocompatible, optically transparent and flexible electrodes by embedding AgNWs just below the surface of the silk fibroin film.

Skin-actuated self-powered devices based on triboelectric nanogenerators (TENGs) have recently garnered increasing attention, as they can be used to develop electronic skins for healthcare, robotic intelligence, and human interface devices. TENGs typically require tribonegative materials to enable the top layers to either be in contact with or be insulated from other specific materials, resulting in suboptimal performance under practical conditions. Here, we describe the fabrication of a soft, t

Abstract Melanin, a biologically occurring pigment featuring broadband optical absorption, ion‐binding affinity including antioxidative and radical‐scavenging properties, and hydration‐dependent electrical conductivity is an ideal natural semiconducting material for interfacing electronics with biological systems. Here, a skin‐mimicking optoelectronic device with a melanin nanoparticle (MNP) dispersion in a protein hydrogel–elastomer hybrid (a mimic of epidermis/dermis layers with melanin) and i

Abstract The ongoing research on printed and flexible electronics is primarily focused on conductive three‐dimensional (3D) print patterning. However, due to the nonhomogeneous distribution of conductive elements in a polymer matrix and their tendency to shrink, 3D‐printed patterns often suffer from low‐printing accuracies and poor mechanical and electrical properties. Herein, poly(vinyl butyral‐ co ‐vinyl alcohol‐ co ‐vinyl acetate) (PVBVA) is reinforced with microwave‐exfoliated graphene to de