Ultrasensitive Detection of Amyloid‑β Using Cellular Prion Protein on the Highly Conductive Au Nanoparticles–Poly(3,4-ethylene dioxythiophene)–Poly(thiophene-3-acetic acid) Composite Electrode

A highly sensitive electrochemical impedance sensor for amyloid beta oligomer (AβO) was fabricated using a cellular prion protein (PrPC) bioreceptor linked with poly­(thiophene-3-acetic acid) transducer. An additional thin layer of poly­(3,4-ethylene dioxythiophene) embedded with gold nanoparticles was employed to provide high electrical conductivity and a large surface area. The sensing performace was investigated in terms of sensitivity and detection range. The fabricated sensor exhibited extremely low detection limit at a subfemtomolar level with a wide detection range from 10–8 to 104 nM and its utility was established in mice infected with Alzheimer’s disease (AD). The developed AβO sensor could be utilized for early diagnosis of AD

Ferrocene-Encapsulated Zn Zeolitic Imidazole Framework (ZIF-8) for Optical and Electrochemical Sensing of Amyloid‑β Oligomers and for the Early Diagnosis of Alzheimer’s Disease

In this work, the ferrocene-encapsulated Zn zeolitic imidazole framework (ZIF-8) was prepared by the self-assembly of Zn ions and 2-methylimidazole and used for the dual detection of amyloid-beta oligomers (AβO), which is the main neuropathological hallmark of Alzheimer’s disease. Ferrocene is an optically and electrochemically active signal which was successfully encapsulated inside of the ZIF-8 and released by the competitive coordination between Zn ions and AβO after being treated with AβO. The released ferrocene content was monitored by ultraviolet/visible spectrophotometry and cyclic voltammetry. The dual determination of AβO played a synergetic role in the quick qualitative and precise quantitative analyses in a wide detection range of 10–5 to 102 μM and good feasibility in artificial cerebrospinal fluid

Highly Stable Potassium-Ion Battery Enabled by Nanoengineering of an Sb Anode

We present the nanoengineering of Sb particles assisted by a conductive and stress-relieving network of carbon quantum dots (CQDs) and poly­(3,4-ethylene dioxythiophene) poly­(styrenesulfonate) (PEDOT:PSS), in the proper design of anode materials with high specific capacity and excellent stability for potassium-ion batteries (KIBs). The nanosized Sb particles are prepared by the CQDs as functional tuners in the morphology and surface, which tune the size to nanolevel and provide fast ionic channels and a soft matrix to relieve the volume changes. As the additional conductive and stress-relieving network layer, PEDOT:PSS offers enhanced electron/ion pathways and maintains the integrity of the Sb@CQD composite electrode. In the KIB, the prepared Sb anode exhibits battery performance with a high specific capacity of 480 mA h g–1 at 0.5 A g–1 and a high-capacity retention of 95.4% over 350 cycles

Cross-Linked Chitosan as an Efficient Binder for Si Anode of Li-ion Batteries

We investigate the use of chitosan (CS) as a new cross-linkable and water-soluble binder for the Si anode of Li-ion batteries. In contrast to the traditional binder utilizing a hydrogen bond and/or van der Waals force-linked anode electrodes, CS can easily form a 3D network to limit the movement of Si particles through the cross-linking between the amino groups of CS and the dialdehyde of glutaraldehyde (GA). Chemical, mechanical, and morphological analyses are conducted by Fourier transform infrared spectroscopy, tensile testing, and scanning electron microscopy. The cross-linked Si/CS-GA anode exhibits an initial discharge capacity of 2782 mAh g^–1 with a high initial Coulombic efficiency of 89% and maintained a capacity of 1969 mAh g^–1 at the current density of 500 mA g^–1 over 100 cycles

Achieving Fast and Reversible Sulfur Redox by Proper Interaction of Electrolyte in Potassium Batteries

Potassium–sulfur batteries have potential for low-cost and high-energy density energy storage. However, it is a challenge to find suitable electrolytes affording liquid environment for intermediate sulfur species to convert at high voltages. In this study, a series of ether/potassium salt systems were systematically studied to investigate the electrochemical stability and function of the electrolytes in sulfur electrochemistry by using in situ ultraviolet–visible and Fourier-transform infrared spectroscopies. Interactions of soluble polysulfides with the electrolyte were critical to the electrochemical performance. Under optimized conditions, the bis(trifluoromethanesulfonyl)imide anion demonstrated moderate interaction and reversible solvation/desolvation of polysulfides. Polar carboxyl groups in poly(acrylic acid) were effective for binding polysulfide in electrodes, enabling reversible sulfur conversions at high working voltages and improved initial Coulombic efficiency. This enhanced battery performance was achieved even using a conventional carbon host with a high sulfur loading of ∼69 wt %, i.e., ∼49 wt % in the cathode

Epoxidized Natural Rubber/Chitosan Network Binder for Silicon Anode in Lithium-Ion Battery

Polymeric binder is extremely important for Si-based anode in lithium-ion batteries due to large volume variation during charging/discharging process. Here, natural rubber-incorporated chitosan networks were designed as a binder material to obtain both adhesion and elasticity. Chitosan could strongly anchor Si particles through hydrogen bonding, while the natural rubber could stretch reversibly during the volume variation of Si particles, resulting in high cyclic performance. The prepared electrode exhibited the specific capacities of 1350 mAh/g after 1600 cycles at the current density of 8 A/g and 2310 mAh/g after 500 cycles at the current density of 1 A/g. Furthermore, the cycle test with limiting lithiation capacity was conducted to study the optimal binder properties at varying degree of the volume expansion of silicon, and it was found that the elastic property of binder material was strongly required when the large volume expansion of Si occurred

Geometry-Controllable Graphene Layers and Their Application for Supercapacitors

A facile and ultrafast method for geometry controllable and vertically transformative 3D graphene architectures is demonstrated. The 2D stacked graphene layers produced by exfoliation of graphite were transformed, e.g., from horizontal to vertical, by applying electric charge (−2 V with 1–3 μAh/cm²). The three-dimensionally transformed graphene layers have maximized surface area as well as high specific capacitance, 410 F g^–1 in LiClO₄/PC electrolyte, which is 4.4 times higher than that of planar (stacked) graphene layers. Furthermore, they can remarkably exhibit 87% of retained capacitance as the scan rate is increased from 100 to 1000 mV s^–1, unlike planar graphene, which displays 61% retention under the same conditions