Preventing aggregation of amyloid beta (Aβ) peptides is a promising strategy for the treatment of Alzheimer’s disease (AD), and gold nanoparticles have previously been explored as a potential anti-Aβ therapeutics. Here we design and prepare 3.3 nm L- and D-glutathione stabilized gold nanoparticles (denoted as L3.3 and D3.3, respectively). Both chiral nanoparticles are able to inhibit aggregation of Aβ42 and cross the blood-brain barrier (BBB) following intravenous administration without noticeable toxicity. D3.3 possesses a larger binding affinity to Aβ42 and higher brain biodistribution compared with its enantiomer L3.3, giving rise to stronger inhibition of Aβ42 fibrillation and better rescue of behavioral impairments in AD model mice. This conjugation of a small nanoparticle with chiral recognition moiety provides a potential therapeutic approach for AD.
Microbial fuel cells (MFCs) are able to directly convert about 50 to 90% of energy from oxidation of organic matters in waste to electricity and have great potential application in broad fields such as wastewater treatment. Unfortunately, the power density of the MFCs at present is significantly lower than the theoretical value because of technical limitations including low bacteria loading capacity and difficult electron transfer between the bacteria and the electrode. We reported a three-dimensional (3D) graphene aerogel (GA) decorated with platinum nanoparticles (Pt NPs) as an efficient freestanding anode for MFCs. The 3D GA/Pt–based anode has a continuous 3D macroporous structure that is favorable for microorganism immobilization and efficient electrolyte transport. Moreover, GA scaffold is homogenously decorated with Pt NPs to further enhance extracellular charge transfer between the bacteria and the anode. The MFCs constructed with 3D GA/Pt–based anode generate a remarkable maximum power density of 1460 mW/m2, 5.3 times higher than that based on carbon cloth (273 mW/m2). It deserves to be stressed that 1460 mW/m2 obtained from the GA/Pt anode shows the superior performance among all the reported MFCs inoculated with Shewanella oneidensis MR-1. Moreover, as a demonstration of the real application, the MFC equipped with the freestanding GA/Pt anode has been successfully applied in driving timer for the first time, which opens the avenue toward the real application of the MFCs.