Cardiovascular diseases are the leading cause of death worldwide, claiming millions of lives every year. Cardiac tissue engineering has emerged as a versatile option for repairing cardiac tissue and helping its regeneration. The use of nanomaterials, particularly nanofiber-based scaffolds combined with biomolecular cues like peptides, has significantly improved the compatibility and efficacy of the scaffolds for cardiac tissue regeneration. By utilising the self-assembly properties of peptides to create nanofiber scaffolds, we can achieve stability that closely mimics the natural components of cardiac tissue, making them perfect for cardiac tissue regeneration. In this review, we highlighted the dynamic process of self-assembly into nanofibers and the use of various self-assembled nanofibers for cardiovascular tissue regeneration, focusing on their roles in antithrombotic, angiogenic, differentiation, proliferation, and anti-atherosclerotic interventions.

Supramolecular gels were developed taking advantage of the assembly of small dipeptides containing a pyrrolo-pyrazole scaffold. Dipeptides were prepared through a robust and ecofriendly synthetic approach from commercially available starting materials, as diazoalcanes and maleimides. By playing with the functionalization of the scaffold, the choice of the natural amino acid and the stereochemistry, we were able to obtain phase selective gels. In particular, one peptidomimetic showed gelation ability and thermoreversibility in aromatic solvents at very low concentrations. Rheology tests showed a typical viscoelastic solid profile, indicating the formation of strong gels stable also upon a high mechanical deformation. NMR studies were performed, allowing to determine the conformational and stereochemical features at the base of the supramolecular interactions.

The bottom-up approach exploits simple building blocks to generate new materials with desired physical and chemical characteristics. Here, we combine two bottom-up routes that occur under mild conditions, self-assembly and sol–gel synthesis, to program the shape and structure of materials. While self-assembly occurs through non-covalent interactions, sol–gel synthesis involves forming covalent bonds. As a proof of concept, we chose the self-assembled peptide Phe-Phe and its fluorinated analogue Phe(4-F)-Phe(4-F) to template the sol–gel process. These peptides were silylated to allow their self-mineralization. Scanning electron microscopy and atomic force microscope analysis revealed the formation of rod-shaped structures for the silylated Phe-Phe while spherical particles were formed by its fluorinated analogue. The size of the particles ranges from nano to micron scale. Fourier transform infrared spectrometry suggested the presence of parallel β-sheet secondary structure and siloxane bond formation that can stabilize these structures. Overall this approach can be adopted for other self-assembled peptides for generating new materials using a bottom-up approach.

The transition from insulator to electro-responsive has been successfully achieved for 3D printed polymers using a smart process based on electro-thermal reorientation followed by charged gas activation. This study extensively investigates the transformation of poly(lactic acid) (PLA) and extends it to polypropylene (PP) and polyethylene terephthalate glycol (PETG). FTIR, Raman spectroscopy, XRD, XPS, SEM, and contact angle measurements confirmed morphological and chemical surface modifications. Electrochemical assays demonstrated that oxygen-containing polymers (PLA and PETG) exhibited superior electroactivity compared to oxygen-free PP. As a proof of concept, treated PLA specimens were used as electrochemical sensors for dopamine, showing catalytic oxidation and a linear detection range from 50 to 1000 μM. This approach enables the transformation of insulating thermoplastics into electro-responsive materials without the need for conductive additives.

In the rapidly advancing field of medical microrobotics, designing robots capable of addressing various challenges—such as imaging, biodegradation, and multifunctionality—is crucial. Departing from conventional research that often focuses on isolated aspects of microrobot functionality, this study presents an innovative approach to comprehensive microrobot design. Soft capsule microrobots that integrate capabilities such as magnetic navigation, autonomous maneuverability, in situ biodegradation, biosafe imaging, and drug delivery are reported. These microrobots are fabricated within the range of 20–120 μm, with a notable throughput of ≈102–103 microrobots per second. Furthermore, their locomotion performance has been demonstrated to remain stable for a period exceeding 10 h, all while employing real-time optical closed-loop control. The incorporation of ultrasound contrast agents not only amplifies imaging resolution but also ensures imaging contrast stability in a biological environment for over a period of 3 h. Second, the intentional integration of enzyme-loaded nanometric polymersomes establishes a self-contained, biodegradable system, accentuating the microrobots’ capacity to degrade without the addition of high enzyme concentrations. This integrated approach lays the groundwork for minimally invasive treatments toward personalized and targeted medicine.

Aggregation-induced emitting (AIE) luminophores are sensitive and easy-to-handle types of probes that allow driving a stimulus-responsive off/on optical tool through the manipulation of the aggregation behavior. In this work, tetraphenylethene (TPE)-phenylalanine derivatives, characterized by strong aggregation-induced luminescence, were obtained through Suzuki–Miyaura cross-coupling reactions. The reaction proved to be straightforwardly applicable in the single amino acid synthesis as well as in the late-stage peptide functionalization by means of both the classical solution-phase reaction and solid-phase synthesis. A comprehensive structural and analytical investigation highlighted the features driving the self-assembly process and its relationship to AIE efficiency. In particular, we showed that the simple slight (asymmetric) extension of the TPE π-systems results in more efficient and brighter emissions, with respect to the simple TPE system itself.

We prepared a small library of short peptidomimetics based on 3-pyrrolo-pyrazole carboxylate, a non-coded γ-amino acid, and glycine or alanine. The robust and eco-friendly synthetic approach adopted allows to obtain the dipeptides in two steps from commercial starting materials. This gives the possibility to shape these materials by electrospinning into micro- and nanofibers, in amounts required to be useful for coating surfaces of biomedical relevance. To promote high quality of electrospun fibers, different substitution patterns were evaluated, all for pure peptide fibers, free of any polymer or additive. The best candidate, which affords a homogeneous fibrous matrix, was prepared in larger amounts, and its biocompatibility was verified. This successful work is the first step to develop a new biomaterial able to produce pristine peptide-based nanofibers to be used as helpful component or stand-alone scaffolds for tissue engineering or for the surface modification of medical devices.

Biofilm formation, a major concern for healthcare systems, is initiated when bacteria adhere to surfaces. Escherichia coli adhesion is mediated by appendages, including type-1 fimbriae and curli amyloid fibers. Antifouling surfaces prevent the adhesion of bacteria to combat biofilm formation. Here, we used single-cell force-spectroscopy to study the interaction between E. coli and glass or two antifouling surfaces: the tripeptide DOPA-Phe(4F)-Phe(4F)-OMe and poly(ethylene glycol) polymer-brush. Our results indicate that both antifoulants significantly deter E. coli initial adhesion. By using two mutant strains expressing no type-1 fimbriae or curli amyloids, we studied the adhesion mechanism. Our results suggest that the bacteria adhere to different antifoulants via separate mechanisms. Finally, we show that some bacteria adhere much better than others, illustrating how the variability of bacterial cultures affects biofilm formation. Our results emphasize how additional study at the single-cell level can enhance our understanding of bacterial adhesion, thus leading to novel antifouling technologies.

Accelerated molecular dynamics (aMD) protocols were assessed on predicting the secondary structure of eight peptides, of which two are helical, three are β-hairpins, and three are disordered. Protocols consisted of combinations of three force fields (ff99SB, ff14SB, ff19SB) and two explicit solvation models (TIP3P and OPC), and were evaluated in two independent aMD simulations, one starting from an extended conformation, the other starting from a misfolded conformation. The results of these analyses indicate that all three combinations performed well on helical peptides. As for β-hairpins, ff19SB performed well with both solvation methods, with a slight preference for the TIP3P solvation model, even though performance was dependent on both peptide sequence and initial conformation. The ff19SB/OPC combination had the best performance on intrinsically disordered peptides. In general, ff14SB/TIP3P suffered the strongest helical bias.