Functionalization of Polyethylene Terephthalate (PETE) Membranes for the Enhancement of Cellular Adhesion in Organ-on-a-Chip Devices.

Experimental reproducibility in organ-on-chip (OOC) devices is a challenging issue, mainly caused by cell adhesion problems, as OOC devices are made of bioinert materials not suitable for natural cellularization of their surfaces. To improve cell adhesion, several surface functionalization techniques have been proposed, among which the simple use of an intermediate layer of adsorbed proteins has become the preferred one by OOC users. This way, the cells use surface receptors to adhere to the adsorbed proteins, which are in turn attached to the surface.

Human Serum Albumin Protein Corona in Prussian Blue Nanoparticles.

Prussian Blue nanoparticles (PBnps) are now popular in nanomedicine thanks to the FDA approval of PB. Despite the numerous papers suggesting or describing the in vivo use of PBnps, no studies have been carried out on the formation of a protein corona on the PBnp surface and its stabilizing role. In this paper, we studied qualitatively and quantitatively the corona formed by the most abundant protein of blood, human serum albumin (HSA).

Nanomaterials for Photothermal Antimicrobial Surfaces.

Microbial infection diseases are a major threat to human health and have become one of the main causes of mortality. The search for novel antimicrobial strategies is an important challenge for the scientific community, considering also the constant increase of antimicrobial resistance and the rise of new diseases. Among the new strategies to combat microbial infections, the photothermal effect seems to be one of the most promising.

Prussian Blue nanoparticles: An FDA-approved substance that may quickly degrade at physiological pH.

Prussian blue (PB) is a coordination polymer based on the FeCNFe sequence. It is an FDA-approved drug, intended for oral use at the acidic pH of the stomach and of most of the intestine track. However, based on FDA approval, a huge number of papers proposed the use of PB nanoparticles (PBnp) under "physiological conditions", meaning pH buffered at 7.

Gold Nanostars Embedded in PDMS Films: A Photothermal Material for Antibacterial Applications.

Bacteria infections and related biofilms growth on surfaces of medical devices are a serious threat to human health. Controlled hyperthermia caused by photothermal effects can be used to kill bacteria and counteract biofilms formation. Embedding of plasmonic nano-objects like gold nanostars (GNS), able to give an intense photothermal effect when irradiated in the NIR, can be a smart way to functionalize a transparent and biocompatible material like polydimethylsiloxane (PDMS).

Modified Mesoporous Silica Nanoparticles with a Dual Synergetic Antibacterial Effect.

Application of mesoporous silica nanoparticles (MSNs) as antifouling/antibacterial carriers is limited and specifically with a dual synergetic effect. In the present work, MSNs modified with quaternary ammonium salts (QASs) and loaded with the biocide Parmetol S15 were synthesized as functional fillers for antifouling/antibacterial coatings. From the family of the MSNs, MCM-48 was selected as a carrier because of its cubic pore structure, high surface area, and high specific pore volume.

Silane-coated magnetic nanoparticles with surface thiol functions for conjugation with gold nanostars.

Small (d∼ 8 nm) magnetite nanoparticles, Fe3O4NP, are prepared and coated with mercaptopropyl trimethoxysilane (MPTS) to form Fe3O4NP@MPTS. In the coating step controlled MPTS/Fe3O4NP molar ratios are used, ranging from 1 to 7.8 × 10(4).

Nanoscale phase separation in coated Ag nanoparticles.

In this paper we report the structural investigation of cysteine and glutathione capped Ag nanoparticles (NPs) by means of transmission electron microscopy (TEM), synchrotron X-ray diffraction (XRD) and pair distribution function (PDF) analysis. The combined use of these probes allowed us to observe the presence of two crystal structures in the coated AgNPs, i.e.

Multicomponent polymeric micelles based on polyaspartamide as tunable fluorescent pH-window biosensors.

PHEA-PEG(5000)-C(16) is a polyaspartamide polymer with appended hydrophilic PEG(5000) functions and hydrophobic n-C(16) units forming biocompatible micelles with a CAC as low as 1.8 × 10(-7) M. The protonation and acidity constants of the polymer's amino and carboxylic groups have been determined by potentiometric titrations at five different concentrations higher than CAC, finding concentration-independent values.

Self-assembled monolayers of silver nanoparticles firmly grafted on glass surfaces: low Ag+ release for an efficient antibacterial activity.

A two-step, easy synthetic strategy in solution has been optimized to prepare authentic monolayers of silver nanoparticles (NP) on MPTS-modified glass surfaces, that were investigated by AFM imaging and by quantitative silver determination techniques. NP in the monolayers remain firmly grafted (i.e.

A micellar multitasking device: sensing pH windows and gauging the lipophilicity of drugs with fluorescent signals.

A multitasking fluorescent device can be obtained by forming micelles of Triton X-100, containing a lipophilic macrocyclic Cu(2+) complex and the coordinating fluorophore Coumarin 343 (C343), which features a COOH moiety. At low pH the two micellised components do not interact, and the fluorescence of Courmarin 343 (C343) is intense. At intermediate pH, C343 is deprotonated and coordinates to the Cu(2+) centre in its apical position, with fluorescence quenching.

Smoothly shifting fluorescent windows: a tunable "off-on-off" micellar sensor for pH.

The position of the window in an "off-on-off" fluorescent pH sensor may be shifted at will along a pH axis by changing the overall charge of the micellar container. This is obtained by using non-ionic Triton X-100 as the surfactant, and by increasing the molar fraction of the anionic sodium dodecyl sulfate (chi(SDS)) as co-surfactant, with pyrene as the fluorophore and a lipophilic tertiary amine and a lipophilic pyridine as pH-switchable quenchers. As the negative micellar charge increases by increasing chi(SDS), the observed pKa of the protonated bases move to higher pH values, followed by the dumb-bell shaped "off-on-off" fluorescence intensity vs.

The Cu(II) complex of a C-lipophilized 13aneN4 macrocycle with an additional protonable amino group as micellar anion receptor.

Three 13aneN4 macrocyclic ligands have been prepared bearing a -CH(2)NHR side arm (R = H, n-C(5)H(11), n-C(10)H(21)) on a carbon atom. When Cu(2+) is complexed in the macrocyclic ring, the amino group of the side arm undergoes an acid-base protonation equilibrium but it is not able to coordinate apically the metal cation even when it is deprotonated. The Cu(2+) complex with the ligand bearing the longest appended aliphatic chain is fully confined inside Triton X-100 micelles, and its ability to bind and sequestrate a series of anions inside micelles has been studied at two different pH values, i.

Fluorescent sensors for Hg(2+) in micelles: a new approach that transforms an ON-OFF into an OFF-ON response as a function of the lipophilicity of the receptor.

A new approach to the use of micelles in the fluorescent sensing of metal cations is proposed and applied to the case of Hg(2+). We demonstrate how it is possible to transform a system from an ON-OFF to an OFF-ON sensor by changing the length of the chain used to lipophilise a ligand that resides inside TritonX-100 micelles together with pyrene as the fluorophore. Three tetrathia-monoaza macrocyclic ligands have been synthesised with the same ring but functionalised on the nitrogen atom with a methyl (C1-NS4), an n-butyl (C4-NS4) or an n-dodecyl (C12-NS4) chain.