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The precise control of sensitivity to external stimuli, for example, impact, friction, and thermal energy, has been emphasized for highly energetic materials, including RDX and HMX. Such sensitivities could be controlled by adjusting the surface area or (in)organic additives; however, increased stability leads to a decrease in the explosives' performance. Here, high-energy-density molecules hosted in inverse opal-like porous carbon (IOC) nanocomposites demonstrate the mechanical stabilization and desensitization of RDX and HMX inside the carbon nanostructure using host-guest chemistry techniques. For this strategy, the uniform, vacant voids of the IOC were used to provide internal crystallization for the impact/frictional stabilization of explosives, and also to enhance the thermal reactivity by the high heat conductivity of IOC initiating detonation by thermally induced hotspot. The weight percentage of high explosives hosted by recrystallization at high temperatures and in vacuum reached ∼70%. After high explosives were embedded inside the IOC, the impact, friction and electrostatic stability was greatly increased (2-2.15-fold, 1.86-1.92-fold, and 1.25-2-fold, respectively) compared with free RDX and HMX. Also, addition of PVP as a binder controlled the effectiveness and efficiency of the carbon template, enabling control of the impact and friction sensitivity from 14.72 J to79.43 J and from 295.81 to 352.80 N, respectively.

BACKGROUND Laparoscopic upper abdominal surgery can cause spontaneous respiration due to diaphragmatic stimulation and intra-abdominal CO2 inflation. Therefore, sufficient muscle relaxation is necessary for a safe surgical environment. METHODS We investigated if the combination of rocuronium and cisatracurium can counteract the delayed onset of cisatracurium's action and delayed recovery of muscle relaxation and whether the dosage of rocuronium, which is metabolized hepatically, can be reduced. A total of 75 patients scheduled for laparoscopic cholecystectomy with an American Society of Anesthesiology physical status I-II, in the age range of 20-60 years, and with a 20-30 kg/m2 body mass index were included in the study. RESULTS The patients were divided into the following groups: combination group (Group RC, rocuronium 0.3 mg/kg and cisatracurium 0.05 mg/kg), rocuronium group (Group R, rocuronium 0.6 mg/kg), and cisatracurium group (Group C, cisatracurium 0.1 mg/kg), and the onset, 25% duration, recovery index, and addition/time ratio were measured. Patients in Group RC exhibited a significantly different addition/time ratio compared with patients in the other two groups (p = 0.003). CONCLUSION During laparoscopic cholecystectomy, the 95% effective dose of rocuronium in combination with cisatracurium is expected to provide a sufficient muscle relaxant effect.

The eye is an extension of the central nervous system (CNS) and contains aqueous humor (AH), which is a fluid rich in biomolecules secreted from intraocular tissues; thus, this organ allows for non-invasive visualization of early changes in CNS disorders. There is a growing interest in developing implantable devices, such as intraocular-lens (IOL), for specific medical uses, including intraocular monitoring. We describe a novel IOL-sensing system for detecting AH biomarkers via biocompatible enzyme-activatable fluorogenic hydrogel sensors. Matrix-metalloproteinase-9, a biomarker of degenerative CNS and eye disorders, was selected as a target. A peptide-probe-incorporated fluorogenic IOL (FIOL) was developed using diacrylamide-group-modified poly(ethyleneglycol) (PEGDAAm) biocompatible hydrogels, adjusting the hydrogel mesh size to allow selective penetration of the target while blocking non-targets, using label-free detection with semi-permanently implantable sensors, and demonstrating the clinical feasibility of FIOL through in vivo testing. This novel FIOL-based sensing system represents a promising approach for liquid biopsy of intraocular fluids.

T1/T2 dual-mode magnetic resonance (MR) contrast agents (DMCAs) have gained much attention because of their ability to improve accuracy by providing two pieces of complementary information with one instrument. However, most of these agents are "always ON" systems that emit MR contrast regardless of their interaction with target cells or biomarkers, which may result in poor target-to-background ratios. Herein, we introduce a rationally designed magnetic relaxation switch (MGRS) for an activatable T1/T2 dual MR imaging system. Redox-responsive heteronanocrystals, consisting of a superparamagnetic Fe3O4 core and a paramagnetic Mn3O4 shell, are synthesized through seed-mediated growth and subsequently surface-modified with polysorbate 80. The Mn3O4 shell acts as both a protector of Fe3O4 in aqueous environments to attenuate T2 relaxation and as a redoxable switch that can be activated in intracellular reducing environments by glutathione. This simultaneously generates large amounts of magnetically decoupled Mn(2+) ions and allows Fe3O4 to interact with the water protons. This smart nanoplatform shows an appropriate hydrodynamic size for the EPR effect (10-100 nm) and demonstrates biocompatibility. Efficient transitions of OFF/ON dual contrast effects are observed by in vitro imaging and MR relaxivity measurements. The ability to use these materials as DMCAs is demonstrated via effective passive tumor targeting for T1- and T2-weighted MR imaging in tumor-bearing mice.

The integration of contrast-enhanced diagnostic imaging and therapy could utilize image guided therapy to plan treatment strategy. Toward this goal, a unique construction and operation of a pseudo metal based photothermal therapeutic agent (PPAM) is introduced by polyaniline (PANI) generation templated on iron oxide metal nanoclusters (MNCs). Notably, MNC core interferes as a catalytic agent and enables aniline polymerization under ambient acidic conditions. The intrusion of transition metal enhanced the proton sensitivity of PANI, which led to pH responsive conversion even at dilute proton concentrations (pH 5, 6) compared to the PANI particles prepared by conventional methods. Under physiological pH, PPAM reveals no special features; however, under low pH conditions, which is a notable characteristic of the cancer microenvironment, PPAM automatically converts into its emeraldine salt (ES) state and thus activates as a photothermal therapeutic agent. Utilizing this specific redox responsive switched off-on behavior of PPAM, precise and systemized photothermal therapy is demonstrated, proving itself as a smart and efficient photothermal therapeutic agent.

Vesicular pH modulates the function of many organelles and plays a pivotal role in cell metabolism processes such as proliferation and apoptosis. Here, we introduce a simple colorimetric redox-polyaniline nanoindicator, which can detect and quantify a broader biogenic pH range with superior sensitivity compared to pre-established trafficking agents employing one-dimensional turn-on of the fluorescence resonance-energy-transfer (FRET) signal. We fabricated polyaniline-based nanoprobes, which exhibited convertible transition states according to the proton levels, as an in situ indicator of vesicular transport pH. Silica-coated Fe3O4-MnO heterometal nanoparticles were synthesised and utilised as a metal oxidant to polymerise the aniline monomer. Finally, silica-coated polyaniline nanoparticles with adsorbed cyanine dye fluorophores Cy3 and Cy7 (FPSNICy3 and FPSNICy7) were fabricated as proton-sensitive nanoindicators. Owing to the selective quenching induced by the local pH variations of vesicular transport, FPSNICy3 and FPSNICy7 demonstrated excellent intracellular trafficking and provided sensitive optical indication of minute proton levels.

Oleyl dextran-coated magnetic nanoclusters (ODMCs) are fabricated for the accurate detection of macrophage-rich atherosclerotic plaques using magnetic resonance (MR) imaging. Dextran is introduced to the cluster surface of magnetic nanocrystals (MNCs) through self-assembly using amphiphilic oleic acid-conjugated dextran (ODex) to provide not only hydrophilicity but also a high affinity to macrophages. Enhanced magnetism of the ODMCs is engineered by optimizing the degree of substitution (DS) of the oleyl group in ODex and the concentration of ODex used for the synthesis of ODMC. Consequently, ODMCs exhibit significantly increased T2 relaxivity and excellent macrophage-targeting ability without cytotoxicity, in vitro. Moreover, in vivo T2-weighted MR imaging after intravenous injection of ODMCs into a rat artery balloon injury model demonstrates considerable MR contrast strength efficacy in the plaques of the injured carotid artery. These novel ODMCs may offer a highly efficient MR imaging nanoprobes for the selective diagnosis of atherosclerosis.

We have synthesized water-stable polyaniline nanoparticles coated with triarmed polyethylene glycol chains using a solvent-shift method and confirmed their colloidal size and aqueous solubility. Furthermore, we have demonstrated that the polyaniline nanoparticles can be doped with biological dopants to produce distinct color changes allowing the detection of live cancer cells.

Immobilizing enzymes on artificially fabricated carriers for their efficient use and easy removal from reactants has attracted enormous interest for decades. Specifically, binding platforms using inorganic nanoparticles have been widely explored because of the benefits of their large surface area, easy surface modification, and high stability in various pH and temperatures. Herein, we fabricated Fe

We present matrix-free methods for fabricating highly luminescent and transparent CdSe/ZnS quantum dot (QD)/polymer nanocomposites utilizing poly(methyl methacrylate) (PMMA)-grafted QDs with various molecular weights. We found that the QD-PMMA nanocomposites prepared by these matrix-free methods were superior to those prepared by a simple blending method in relation to their optical property, QD dispersion, and quantum efficiency (QE). In particular, a matrix-free nanocomposite containing PMMA with a molecular weight of 2000 had the highest QE (52.8%) and transmittance of all the samples studied even at a very high QD concentration (49 wt%). This finding was attributed to the enhanced passivation of the QD surface due to the higher grafting density of the PMMA ligands and reduced energy transfer due to more uniform dispersion of QDs. Finally, we applied the nanocomposites to LED devices, and found that the matrix-free nanocomposite exhibited a higher color conversion efficiency and smaller redshift in the peak emission wavelength than that prepared using a simple blending method.

Oleyl dextran-coated magnetic nanoclusters (ODMCs) are fabricated for the accurate detection of macrophage-rich atherosclerotic plaques using magnetic resonance (MR) imaging. Dextran is introduced to the cluster surface of magnetic nanocrystals (MNCs) through self-assembly using amphiphilic oleic acid-conjugated dextran (ODex) to provide not only hydrophilicity but also a high affinity to macrophages. Enhanced magnetism of the ODMCs is engineered by optimizing the degree of substitution (DS) of the oleyl group in ODex and the concentration of ODex used for the synthesis of ODMC. Consequently, ODMCs exhibit significantly increased T2 relaxivity and excellent macrophage-targeting ability without cytotoxicity, in vitro. Moreover, in vivo T2-weighted MR imaging after intravenous injection of ODMCs into a rat artery balloon injury model demonstrates considerable MR contrast strength efficacy in the plaques of the injured carotid artery. These novel ODMCs may offer a highly efficient MR imaging nanoprobes for the selective diagnosis of atherosclerosis.

Immobilizing enzymes on artificially fabricated carriers for their efficient use and easy removal from reactants has attracted enormous interest for decades. Specifically, binding platforms using inorganic nanoparticles have been widely explored because of the benefits of their large surface area, easy surface modification, and high stability in various pH and temperatures. Herein, we fabricated Fe3O4 encapsulated 'sea-urchin' shaped nickel-silicate nanoparticles with a facile synthetic route. The enzymes were then rapidly and easily immobilized with poly-histidine tags (His-tags) and nickel ion affinity. Porous nickel silicate covered nanoparticles achieved a high immobilization capacity (85 μg mg-1) of His-tagged tobacco etch virus (TEV) protease. To investigate immobilized TEV protease enzymatic activity, we analyzed the cleaved quantity of maltose binding protein-exendin-fused immunoglobulin fusion protein, which connected with the TEV protease-specific cleavage peptide sequence. Moreover, TEV protease immobilized nanocomplexes conveniently removed and recollected from the reactant by applying an external magnetic field, maintained their enzymatic activity after reuse. Therefore, our newly developed nanoplatform for His-tagged enzyme immobilization provides advantageous features for biotechnological industries including recombinant protein processing.