Jungbae Kim

We have developed armored single-enzyme nanoparticles (SENs) that surround each enzyme molecule with a porous composite organic/inorganic network of less than a few nanometers thick. This approach has significantly stabilized two proteases (α-chymotrypsin, CT, and trypsin, TR), and the armor network around CT is sufficiently thin and porous that it does not place a large mass-transfer limitation on the substrate. These new hybrid enzyme nanostructures offer great potential as a method to stabili

Photothermal (PT)-enhanced Fenton-based chemodynamic therapy (CDT) has attracted a significant amount of research attention over the last five years as a highly effective, safe, and tumor-specific nanomedicine-based therapy. CDT is a new emerging nanocatalyst-based therapeutic strategy for the <i>in situ</i> treatment of tumors via the Fenton reaction or Fenton-like reaction, which has got fast progress in recent years because of its high specificity and activation by endogenous substances. A va

Nanofibers consisting of enzyme–polymer composites have been prepared by directly electrospinning a solution of surfactant-stabilized enzyme and polymer in toluene. Additional treatment with glutaraldehyde could greatly stabilize the enzyme activity of the fibers, which could be maintained in a buffer under shaking conditions for more than two weeks. The nanofibers also showed great improvement in the enzyme activity over bulk films as a result of increased mass-transfer for substrate molecules

Multifunctional nanocomposites (M-CLEAs) of enzymes and magnetic nanoparticles (M-NPs) were fabricated in hierarchically ordered, mesocellular, mesoporous silica (HMMS; see Figure) by a simple process involving the co-adsorption of enzyme molecules and magnetic nanoparticles into HMMS followed by glutaraldehyde (GA) treatment. These nanocomposites are magnetically separable and highly stable and active. In particular, M-CLEA–lipase shows no decrease of lipase activity at all in the presence of p

It is reported that glucose oxidase (GOx)-copper hybrid nanoflowers embedded with Fe₃ O₄ magnetic nanoparticles (MNPs) exhibit superior peroxidase-mimicking activity as well as substrate channeling for glucose detection. This is due to the synergistic integration of GOx, crystalline copper phosphates and MNPs being in close proximity within the nanoflowers. The preparation of MNP-embedded GOx-copper hybrid nanoflowers (MNPs-GOx NFs) begins with the facile conjugation of ami

An extracellular protease has been purified from the extreme halophile, Halobacterium halobium. The irreversible inactivation kinetics of this halophilic protease in salt concentrations below 4M consists of autolytic and nonautolytic (steady-state denaturation) components. Addition of organic solvents has a dramatic effect on enzyme stability in low salt media. For example, in 0.36M NaCl, the inactivation rate constant for the nonautolytic component in 20% (v/v) ethylene glycol is ca. 3 orders o