Failure progression and toughening mechanism of 3D-printed nacre-like structures under in-plane compression.

Nacre (also called mother-of-pearl) is known to have a delicate balance of stiffness, strength, and toughness, which originates from its 'brick-and-mortar' structure. In this study, nacre-like structures are fabricated using a high-resolution, multi-material 3D printer, where two different polyurethane acrylates (one that is hard and another that is soft) are used to represent the tablets and matrix. Six nacre-like structures are designed and fabricated to explore the influence of geometric parameters on the mechanical behaviors.

Cerium oxide-graphene as the matrix for cholesterol sensor.

A simple and sensitive electrogenerated chemiluminescence (ECL) cholesterol biosensor was prepared based on cerium oxide-graphene (CeO(2)-graphene) composites as an efficient matrix. CeO(2)-graphene composites were prepared by depositing CeO(2) onto graphene and were characterized by scanning electron microscopy. The experimental results demonstrated that CeO(2)-graphene could catalyze the ECL of a luminol-H(2)O(2) (hydrogen peroxide) system to amplify the luminol ECL signal greatly.

Simultaneous determination of ascorbic acid, dopamine, uric acid and tryptophan on gold nanoparticles/overoxidized-polyimidazole composite modified glassy carbon electrode.

A novel electrode was developed through electrodepositing gold nanoparticles (GNPs) on overoxidized-polyimidazole (PImox) film modified glassy carbon electrode (GCE). The combination of GNPs and the PImox film endowed the GNPs/PImox/GCE with good biological compatibility, high selectivity and sensitivity and excellent electrochemical catalytic activities towards ascorbic acid (AA), dopamine (DA), uric acid (UA) and tryptophan (Trp). In the fourfold co-existence system, the peak separations between AA-DA, DA-UA and UA-Trp were large up to 186, 165 and 285 mV, respectively.

A biosensor for cholesterol based on gold nanoparticles-catalyzed luminol electrogenerated chemiluminescence.

A novel cholesterol biosensor was prepared based on gold nanoparticles-catalyzed luminol electrogenerated chemiluminescence (ECL). Firstly, l-cysteine-reduced graphene oxide composites were modified on the surface of a glassy carbon electrode. Then, gold nanoparticles (AuNPs) were self-assembled on it.

Au-nanoclusters incorporated 3-amino-5-mercapto-1,2,4-triazole film modified electrode for the simultaneous determination of ascorbic acid, dopamine, uric acid and nitrite.

A novel biosensor has been constructed by the electrodeposition of Au-nanoclusters (nano-Au) on poly(3-amino-5-mercapto-1,2,4-triazole) (p-TA) film modified glassy carbon electrode (GCE) and employed for the simultaneous determination of dopamine (DA), ascorbic acid (AA), uric acid (UA) and nitrite (NO(2)(-)). NH(2) and SH groups exposed to the p-TA layer are helpful for the electrodeposition of nano-Au. The combination of nano-Au and p-TA endow the biosensor with large surface area, good biological compatibility, electricity and stability, high selectivity and sensitivity and flexible and controllable electrodeposition process.

Glucose biosensor based on titanium dioxide-multiwall carbon nanotubes-chitosan composite and functionalized gold nanoparticles.

In this paper, a new glucose biosensor was prepared. At first, Prussian blue (PB) was electrodeposited on a glassy carbon electrode (GCE) modified by titanium dioxide-multiwall carbon nanotubes-chitosan (TiO(2)-MWNTs-CS) composite, and then gold nanoparticles functionalized by poly(diallyldimethylammonium chloride) (PDDA-Au) were adsorbed on the PB film. Finally, the negatively charged glucose oxidase (GOD) was self-assembled on to the positively charged PDDA-Au.