Hierarchical Self-Assembly of Halogen-Bonded Block Copolymer Complexes into Upright Cylindrical Domains

Self-assembly of block copolymers into well-defined, ordered arrangements of chemically distinct domains is a reliable strategy for preparing tailored nanostructures. Microphase separation results from the system, minimizing repulsive interactions between dissimilar blocks and maximizing attractive interactions between similar blocks. Supramolecular methods have also achieved this separation by introducing small-molecule additives binding specifically to one block by noncovalent interactions. Here, we use halogen bonding as a supramolecular tool that directs the hierarchical self-assembly of low-molecular-weight perfluorinated molecules and diblock copolymers. Microphase separation results in a lamellar-within-cylindrical arrangement and promotes upright cylindrical alignment in films upon rapid casting and without further annealing. Such cylindrical domains with internal lamellar self-assemblies can be cleaved by solvent treatment of bulk films, resulting in separated and segmented cylindrical micelles stabilized by halogen-bond-based supramolecular crosslinks. These features, alongside the reversible nature of halogen bonding, provide a robust modular approach for nanofabricatio

Proline enantiomers discrimination by (L)-prolinated porphyrin derivative Langmuir-Schaefer films: proof of concept for chiral sensing applications

A porphyrin derivative functionalized with the L-enantiomer of proline amino acid was characterized at the air-pure water interface of the Langmuir trough. The porphyrin derivative was dissolved in dichloromethane solution, spread at the air-subphase interface and investigated by acquiring the surface pressure vs. area per molecule Langmuir curves. It is worth observing that the behavior of the molecules of the porphyrin derivative floating film was substantially influenced by the presence of L-proline amino acid dissolved in the subphase (10(-5) M); on the contrary, the physical chemical features of the floating molecules were only slightly influenced by the D-proline dissolved in the subphase. Such an interesting chirality-driven selection was preserved when the floating film was transferred onto solid supports by means of the Langmuir-Schaefer method, but it did not emerge when a spin-coating technique was used for the layering of the tetrapyrrolic derivatives. The obtained results represent proof of concept for the realization of active molecular layers for chiral discrimination: porphyrin derivatives, due to their intriguing spectroscopic and supramolecular properties, can be functionalized with the chiral molecule that should be detected. Moreover, the results emphasize the crucial role of the deposition technique on the features of the sensing layers

Proline Enantiomers Discrimination by (L)-Prolinated Porphyrin Derivative Langmuir–Schaefer Films: Proof of Concept for Chiral Sensing Applications

A porphyrin derivative functionalized with the L-enantiomer of proline amino acid was characterized at the air–pure water interface of the Langmuir trough. The porphyrin derivative was dissolved in dichloromethane solution, spread at the air–subphase interface and investigated by acquiring the surface pressure vs. area per molecule Langmuir curves. It is worth observing that the behavior of the molecules of the porphyrin derivative floating film was substantially influenced by the presence of L-proline amino acid dissolved in the subphase (10−5 M); on the contrary, the physical chemical features of the floating molecules were only slightly influenced by the D-proline dissolved in the subphase. Such an interesting chirality-driven selection was preserved when the floating film was transferred onto solid supports by means of the Langmuir–Schaefer method, but it did not emerge when a spin-coating technique was used for the layering of the tetrapyrrolic derivatives. The obtained results represent proof of concept for the realization of active molecular layers for chiral discrimination: porphyrin derivatives, due to their intriguing spectroscopic and supramolecular properties, can be functionalized with the chiral molecule that should be detected. Moreover, the results emphasize the crucial role of the deposition technique on the features of the sensing layers

A Stimuli-Responsive Nanocomposite for 3D Anisotropic Cell-Guidance and Magnetic Soft Robotics

Stimuli-responsive materials have the potential to enable the generation of new bioinspired devices with unique physicochemical properties and cell-instructive ability. Enhancing biocompatibility while simplifying the production methodologies, as well as enabling the creation of complex constructs, i.e., via 3D (bio)printing technologies, remains key challenge in the field. Here, a novel method is presented to biofabricate cellularized anisotropic hybrid hydrogel through a mild and biocompatible process driven by multiple external stimuli: magnetic field, temperature, and light. A low-intensity magnetic field is used to align mosaic iron oxide nanoparticles (IOPs) into filaments with tunable size within a gelatin methacryloyl matrix. Cells seeded on top or embedded within the hydrogel align to the same axes of the IOPs filaments. Furthermore, in 3D, C2C12 skeletal myoblasts differentiate toward myotubes even in the absence of differentiation media. 3D printing of the nanocomposite hydrogel is achieved and creation of complex heterogeneous structures that respond to magnetic field is demonstrated. By combining the advanced, stimuli-responsive hydrogel with the architectural control provided by bioprinting technologies, 3D constructs can also be created that, although inspired by nature, express functionalities beyond those of native tissue, which have important application in soft robotics, bioactuators, and bionic devices

Le immunoglobuline per via endovenosa nel trattamento delle neuropatie infantili

Agli inizi degli anni ’80, l’avvento dei preparati di immunoglobuline per via endovenosa (IVIG) nella la terapia sostitutiva delle ipo-agammaglobulinemie, ha radicalmente cambiato la prognosi dei pazienti con immunodeficienze umorali 1. Fino ad allora infatti erano utilizzabili solo preparati per via intramuscolare, con importanti limitazioni legate ai volumi di liquido iniettabili per questa via e la sostituzione degli anticorpi carenti era perciò poco soddisfacente. La disponibilità delle IVIG (quindi la possibilità di somministrare grandi volumi = quantità di IgG) non solo ha consentito la completa sostituzione dei difetti anticorpali, ma ha anche aperto la strada ad altri impieghi sfruttandone le attività immunomodulanti e antinfiammatorie prima sconosciute e rivelatesi in modo del tutto occasionale. Fu Imbach che casualmente osservò in un paziente con difetto anticorpale e piastrinopenia non solo la normalizzazione delle IgG, ma anche del numero di piastrine, in corso di terapia con IVIG e intraprese il primo studio con IVIG in pazienti con porpora trombocitopenia idiopatica, dimostrandone una eccellente efficacia 2. Da allora i campi applicativi si sono estesi a tutte quelle malattie autoimmuni e infiammatorie per le quali i risultati della terapia classica erano insoddisfacenti e si è focalizzata l’attenzione sui meccanismi attraverso cui le IVIG esercitano la loro azione antinfiammatoria e immunomodulante. Si può dire che ad oggi pressoché tutte le malattie autoimmuni – e le malattie neuromuscolari in particolare per le loro caratteristiche invalidanti ed evolutive – sono state oggetto di tentativi terapeutici con IVIG. I risultati non sono stati sempre incoraggianti e, in considerazione dell’alto costo dei preparati, si è sentita e si sente l’esigenza di porre ordine e di rivedere criticamente tutta la letteratura sull’argomento per dare indicazioni più precise, in accordo ai criteri EBM, sull’impiego di tali preparati. Ormai sono numerose le indicazioni e le consensus redatte sia da Neurologi che da Immunologi; a queste si aggiungono le direttive ufficiali, emanate dagli organi di controllo statali (FDA, WHO, AIFA) che ne approvano le indicazioni per alcune malattie e ne coprono il costo a carico dei sistemi sanitari nazionali. Tuttavia la approvazione riguarda un numero estremamente esiguo di patologie e tuttora le IVIG vengono spesso utilizzate off label