A bistren cryptand with a remote thioether function: Cu(ii) complexation in solution and on the surface of gold nanostars

A di-copper(ii) complex is formed in a bis-tren cage featuring a thioether function, capable of grafting on a monolayer of gold nanostars

Light Emitting Molecular Devices Based on Transition Metals

Multicomponent systems have been designed, which are able to perform defined functions related to light emission and quenching. The desired function can be switched ON/OFF by the operator through a chemical input, either a change of pH or a variation of the redox potential. Transition metals (e.g. Ni(II), Cu(II)) are key constituents within the considered systems, playing a distinctive architectural role and favouring electron transfer processes

Increased Antibacterial and Antibiofilm Properties of Silver Nanoparticles Using Silver Fluoride as Precursor.

Silver nanoparticles were produced with AgF as the starting Ag(I) salt, with pectin as the reductant and protecting agent. While the obtained nanoparticles (pAgNP-F) have the same dimensional and physicochemical properties as those already described by us and obtained from AgNO3 and pectin (pAgNP-N), the silver nanoparticles from AgF display an increased antibacterial activity against E. coli PHL628 and Staphylococcus epidermidis RP62A (S. epidermidis RP62A), both as planktonic strains and as their biofilms with respect to pAgNP-N. In particular, a comparison of the antimicrobial and antibiofilm action of pAgNP-F has been carried out with pAgNP-N, pAgNP-N and added NaF, pure AgNO3, pure AgF, AgNO3 and added NaF and pure NaNO3 and NaF salts. By also measuring the concentration of the Ag+ cation released by pAgNP-F and pAgNP-N, we were able to unravel the separate contributions of each potential antibacterial agent, observing an evident synergy between p-AgNP and the F- anion: the F- anion increases the antibacterial power of the p-AgNP solutions even when F- is just 10 µM, a concentration at which F- alone (i.e., as its Na+ salt) is completely ineffective

Molecular machinery working with transition metal ions.

In this plenary lecture - given on the assignement of the "Medaglia Nasini" prize - a review of the author's research is presented, in the ion translocation and controlled molecular rearrangements are

Electrochemical assemblig/disasembling of helicates displaying hysteresis: storing informations in solution.

Double Helicates of Cu(I) and monomeric species of Cu(II) can be obtained using the same ligands under the same conditions. This give bistable systems whose interconversion presents hysteresis and may be used to store informations in solutio

Micelles as containers for self-assembled nanodevices

Micelles of nanometric dimensions are used to self-assemble two or more lipophilic molecular components. The combination of their functions produces new functions, such as fluorescent sensing of cations and pH window

Gold nanostars for superficial diseases: A promising tool for localized hyperthermia?

A review about the use of the photothermal effect exerted by gold nanostars in superficial deseases therapie

Prussian blue nanoparticles as a versatile photothermal tool

Prussian blue (PB) is a coordination polymer studied since the early 18th century, historically known as a pigment. PB can be prepared in colloidal form with a straightforward synthesis. It has a strong charge-transfer absorption centered at ~700 nm, with a large tail in the Near-IR range. Irradiation of this band results in thermal relaxation and can be exploited to generate a local hyperthermia by irradiating in the so-called bio-transparent Near-IR window. PB nanoparticles are fully biocompatible (PB has already been approved by FDA) and biodegradable, this making them ideal candidates for in vivo use. While papers based on the imaging, drug-delivery and absorbing properties of PB nanoparticles have appeared and have been reviewed in the past decades, a very recent interest is flourishing with the use of PB nanoparticles as photothermal agents in biomedical applications. This review summarizes the syntheses and the optical features of PB nanoparticles in relation to their photothermal use and describes the state of the art of PB nanoparticles as photothermal agents, also in combination with diagnostic techniques

Transition metals as switches

In this article it is demonstrated that transition metals are among the best candidates for the role of molecular switches, on account of the following peculiar properties:  (i) They can form couples of consecutive oxidation states, A and B, easily interconverted through a fast and reversible one-electron redox change. The relative stability of the two states (which is expressed exactly by the standard electrode potential associated with the half-reaction) can be modulated by properly varying the coordinative environment around the metal center. (ii) The one-electron change in most cases modifies drastically the properties of the metal center (stereochemical preferences, magnetism, electron-transfer tendencies, binding affinity toward a donor atom)