Currently, antibiotic-resistant bacteria represent a serious threat to public health worldwide. Biofilm formation potentiates both virulence and antibiotic resistance of bacteria. Therefore, the discovery of new antibacterial and antibiofilm compounds is an issue of paramount importance to combat and prevent hard-to-treat bacterial infections. Zeolitic-imidazolate-frameworks (ZIFs) are metallo-organic compounds known to have various interesting chemical and biological applications, including antibacterial properties. In this study, we synthesized ZIF-67 nanoparticles, formed by imidazolate anions and cobalt cations, and found that they inhibit the growth of Acinetobacter baumannii, Pseudomonas aeruginosa, and Staphylococcus aureus. Sub-inhibitory concentrations of ZIF-67 were also able to significantly reduce the biomass of pre-established biofilms of these pathogenic bacteria. On the other hand, the ZIF-67 nanoparticles had null or low cytotoxicity in mammalian cells at those concentrations showing antibacterial or antibiofilm activities. Thus, our results reveal the potential of ZIF-67 nanoparticles to be used against pathogenic bacteria.

The complexity and overall burden of Parkinson’s disease (PD) require new pharmacological approaches to counteract the symptomatology while reducing the progressive neurodegeneration of affected dopaminergic neurons. Since the pathophysiological signature of PD is characterized by the loss of physiological levels of dopamine (DA) and the misfolding and aggregation of the alpha-synuclein (α-syn) protein, new proposals seek to restore the lost DA and inhibit the progressive damage derived from pathological α-syn and its impact in terms of oxidative stress. In this line, nanomedicine (the medical application of nanotechnology) has achieved significant advances in the development of nanocarriers capable of transporting and delivering basal state DA in a controlled manner in the tissues of interest, as well as highly selective catalytic nanostructures with enzyme-like properties for the elimination of reactive oxygen species (responsible for oxidative stress) and the proteolysis of misfolded proteins. Although some of these proposals remain in their early stages, the deepening of our knowledge concerning the pathological processes of PD and the advances in nanomedicine could endow for the development of potential treatments for this still incurable condition. Therefore, in this paper, we offer: (i) a brief summary of the most recent findings concerning the physiology of motor regulation and (ii) the molecular neuropathological processes associated with PD, together with (iii) a recapitulation of the current progress in controlled DA release by nanocarriers and (iv) the design of nanozymes, catalytic nanostructures with oxidoreductase-, chaperon, and protease-like properties. Finally, we conclude by describing the prospects and knowledge gaps to overcome and consider as research into nanotherapies for PD continues, especially when clinical translations take place.

Detection methods and analytical devices have drawn increasing attention in recent years due to their direct impact on early detection, monitoring and diagnosis of disease in medical research. In this work, we describe a simple but so far unrecognized label-free method for surface-bound analyte detection, which could be applicable to a wide range of substances. In this respect, the feasibility and practical aspects of a micrometer-scale, poly-l-lysine-based, solid-phase assay for label-free analyte detection with electrostatic read-out are investigated. Micropatterned poly-l-lysine layers were produced using soft-lithography on mica and their electrostatic surface potential was determined using Kelvin-probe Force Microscopy. Ribose, a natural sugar, was used as analyte. Upon exposure to ribose, the surface potential changed from positive to negative in a reversible manner. We report for the first time the use of an electrostatic principle for assay read-out. This purely physical effect could be used to develop label- and marker-free assays for sugars, various other substances or, possibly, biosensors.