Hydrogel opals, exhibiting striking iridescence while being soft and gelatinous, can be synthesized by covalent bonding (through crosslinkers) of self‐assembled hydrogel nanoparticles, which consist of N‐isopropyl‐acrylamide copolymers with reactive side groups. Beyond their aesthetic value (see Figure and also cover) hydrogel opals are potentially useful as thermo‐ or electrochromic gel sensors.
Recently emerged metallic zinc (Zn) is a new generation of promising candidates for bioresorbable medical implants thanks to its essential physiological relevance, mechanical strength, and more matched degradation pace to that of tissue healing. Zn‐based metals exhibit excellent biocompatibility in various animal models. However, direct culture of cells on Zn metals yields surprisingly low viability, indicating high cytotoxicity of Zn. This contradicting phenomenon should result from the different degradation mechanisms between in vitro and in vivo. To solve this puzzle, the roles of all major players, i.e., zinc phosphate (ZnP), zinc oxide (ZnO), zinc hydroxide (Zn(OH)
2
), pH, and Zn
2+
, which are involved in the degradation process are examined. Data shows that ZnP, not ZnO or Zn(OH)
2
, significantly enhances its biocompatibility. The mild pH change during degradation also has no significant impact on cell viability. Collectively, ZnP appears to be the key to controlling the biocompatibility of Zn implants and could be applied as a novel surface coating to improve biocompatibility of different implants.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.