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A series of dumbbell-shaped nanocomposite materials of poly(dimethylsiloxanes) (PDMSs) and polyhedral oligomeric silsesquioxanes (POSSs) were synthesized through hydrosilylation reactions of allyl-and vinyl-POSS and hydrideterminated PDMS. The chemical structures of the dumbbellshaped materials, so-called POSS-PDMS-POSS triblocks, were characterized by 1 H NMR and FT-IR spectroscopy. The molecular weights of the triblock polymers were determined by gel permeation chromatography (GPC). Their size was analyzed by small-angle neutron scattering (SANS) and pulsed-field gradient stimulated echo (PFG STE) NMR experiments. The impact of POSS on the molecular mobility of the PDMS middle chain was observed by using 1 H spin−spin (T 2 ) relaxation NMR. In contrast to the PDMS melts, the triblocks showed an increase in mobility with increasing molecular weight over the range studied due to the reduced relative concentration of constraints imposed by the end-tethered nanoparticles. The triblock systems were used to compare the impact of tethered nanoparticles on the mobility of the linear component compared to the mobility of the polymer in conventional blended nanocomposites. The tethered nanoparticles were found to provide more reinforcement than physically dispersed particles especially at high molecular weights (low particle concentration). The physical blends showed an apparent percolation threshold behavior.

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A novel metal composite material based on zirconium dioxide decorated gold nanoparticles (ZrO2@AuNPs), copper (I) oxide at manganese (IV) oxide (Cu2O@MnO2) and immobilized choline oxidase (ChOx) onto a glassy carbon electrode (GCE) (ChOx/Cu2O@MnO2‐ZrO2@AuNPs/GCE) has been developed for enhancing the electro‐catalytic property, sensitivity and stability of the amperometric choline biosensor. The ChOx/Cu2O@MnO2‐ZrO2@AuNPs/GCE displayed an excellent electrocatalytic response to the oxidation of the byproduct H2O2 from the choline catalyzed reaction, which exhibited a charge transfer rate constant (Ks) of 0.97 s−1, a diffusion coefficient value (D) of 4.50×10−6 cm2 s−1, an electroactive surface area (Ae) of 0.97 cm2 and a surface concentration (γ) of 0.54×10−8 mol cm−2. The modified electrode also provided a wide linear range of choline concentration from 0.5 to 1,000.0 μM with good sensitivity (97.4 μA cm−2 mM−1) and low detection limit (0.3 μM). The apparent Michaelis‐Menten constant was found to be 0.08 mM with Imax of 0.67 μA. This choline biosensor presented high repeatability (%RSD=2.9, n=5), excellent reproducibility (%RSD=2.9, n=5), long time of use (n=28 with %I>50.0 %) and good selectivity without interfering effects from possible electroactive species such as ascorbic acid, aspirin, amoxicillin, caffeine, dopamine, glucose, sucrose and uric acid. This optimal method was successfully applied for choline measurement in prepared human blood samples which demonstrated accurate and excellent reliability in the recovery range from 96.7 to 102.0 %.