Raffaella Lettieri

Dr. Raffaella Lettieri

orcid

Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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4 October 2020 in Molecules
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Journal Article
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Manuela StefanelliManuela Stefanelli
Manuela Stefanelli
FMFederica Mandoj
Federica Mandoj
GMGabriele Magna
Gabriele Magna
RLRaffaella Lettieri
Raffaella Lettieri
Mariano VENANZIMariano VENANZI
Mariano VENANZI
DMDonato Monti
Donato Monti
An overview of the solvent-driven aggregation of a series of chiral porphyrin derivatives studied by optical methods (UV/Vis, fluorescence, CD and RLS spectroscopies) is herein reported. The investigated porphyrins are characterized by the presence in the meso-positions of glycol-, steroidal- and glucosteroidal moieties, conferring amphiphilicity and solubility in aqueous media to the primarily hydrophobic porphyrin platform. Aggregation of the macrocycles is driven by a change in bulk solvent composition, forming architectures with supramolecular chirality, steered by the stereogenic centers on the porphyrin peripheral positions. The aggregation behavior and chiroptical properties of the final aggregated species strongly depend on the number and stereogenicity of the ancillary groups that dictate the mutual spatial arrangement of the porphyrin chromophores and their further organization in larger structures, usually detectable by different microscopies, such as AFM and SEM. Kinetic studies are fundamental to understand the aggregation mechanism, which is frequently found to be dependent on the substrate concentration. Additionally, Molecular Mechanics calculations can give insights into the intimate nature of the driving forces governing the self-assembly process. The critical use of these combined methods can shed light on the overall self-assembly process of chirally-functionalized macrocycles, with important implications on the development of chiral porphyrin-based materials.

16 September 2025 in ACS Sustainable Chemistry & Engineering
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Journal Article
Open access
RLRaffaella Lettieri
Raffaella Lettieri
ACAlice Caravella
Alice Caravella
GQGiulia Quintarelli
Giulia Quintarelli
CDCadia D’oTtavi
Cadia D’oTtavi
SLSilvia Licoccia
Silvia Licoccia
Emanuela GattoEmanuela Gatto
Emanuela Gatto
Grapevine shoots, a viticultural residue rich in cellulose (∼34%) and lignin (20–27%), were valorized through an eco-designed biorefinery process integrating autoclave-assisted pretreatment and organosolv extraction. This approach enabled the corecovery of cellulose and lignin under mild, sulfur-free conditions, followed by a chlorine-free bleaching that retained ∼7 wt % lignin within the cellulose. Rather than being removed, lignin was preserved as a natural additive for its antioxidant and UV-shielding functions, reducing the need for synthetic components. The lignin-containing cellulose was acetylated (DS ≈ 1.7) and plasticized with glycerol to produce biodegradable films. These films fully disintegrated under home composting within 8 weeks, outperforming commercial cellulose acetate. The process aligns with green chemistry principles and EU circular economy goals, offering a sustainable route to multifunctional bioplastics from agricultural waste.

13 January 2023 in Nanomaterials
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Journal Article
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NFNicola Forlano
Nicola Forlano
RBRaffaella Bucci
Raffaella Bucci
AAAlessandro Alessandro
Alessandro Alessandro
Mariano VENANZIMariano VENANZI
Mariano VENANZI
EPErnesto Placidi
Ernesto Placidi
Emanuela GattoEmanuela Gatto
Emanuela Gatto
Structures composed of alternating α and β amino acids can give rise to peculiar secondary structural motifs, which could self-assemble into complex structures of controlled geometries. This work describes the self-assembly properties of an α,β-peptide, containing three units of syn H2-(2-F-Phe)-h-PheGly-OH, able to self-organize on surfaces into a fascinating supramolecular rope. This material was characterized by AFM, electronic conduction and fluorescence measurements. Molecular dynamics simulations showed that this hexapeptide can self-assemble into an antiparallel β-sheet layer, stabilized by intermolecular H-bonds, which, in turn, can self-assemble into many side-by-side layers, due to π-π interactions. As a matter of fact, we demonstrated that in this system, the presence of aromatic residues at the intramolecular interface promoted by the alternation of α,β-amino-acids in the primary sequence, endorses the formation of a super-secondary structure where the aromatic groups are close to each other, conferring to the system good electron conduction properties. This work demonstrates the capability and future potential of designing and fabricating distinctive nanostructures and efficient bioelectronic interfaces based on an α,β-peptide, by controlling structure and interaction processes beyond those obtained with α- or β-peptides alone.

3 August 2022 in Energies
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Journal Article
Open access
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Emanuela GattoEmanuela Gatto
Emanuela Gatto
RLRaffaella Lettieri
Raffaella Lettieri
Luigi VesceLuigi Vesce
Luigi Vesce
Mariano VENANZIMariano VENANZI
Mariano VENANZI
In September 2015, the ONU approved the Global Agenda for Sustainable Development, by which all countries of the world are mobilized to adopt a set of goals to be achieved by 2030. Within these goals, the aim of having a responsible production and consumption, as well as taking climate action, made is necessary to design new eco-friendly materials. Another important UN goal is the possibility for all the countries in the world to access affordable energy. The most promising and renewable energy source is solar energy. Current solar cells use non-biodegradable substrates, which generally contribute to environmental pollution at the end of their life cycles. Therefore, the production of green and biodegradable electronic devices is a great challenge, prompted by the need to find sustainable alternatives to the current materials, particularly in the field of dye-sensitized solar cells. Within the green alternatives, biopolymers extracted from biomass, such as polysaccharides and proteins, represent the most promising materials in view of a circular economy perspective. In particular, peptides, due to their stability, good self-assembly properties, and ease of functionalization, may be good candidates for the creation of dye sensitized solar cell (DSSC) technology. This work shows an overview of the use of peptides in DSSC. Peptides, due to their unique self-assembling properties, have been used both as dyes (mimicking natural photosynthesis) and as templating materials for TiO2 morphology. We are just at the beginning of the exploitation of these promising biomolecules, and a great deal of work remains to be done.

26 May 2024 in ACS Sustainable Resource Management
Verified
Journal Article
Closed access
ACAlice Caravella
Alice Caravella
RLRaffaella Lettieri
Raffaella Lettieri
RVRocco Vezza
Rocco Vezza
Emanuela GattoEmanuela Gatto
Emanuela Gatto

4 September 2025 in European Journal of Pharmaceutics and Biopharmaceutics
Verified
Journal Article
Open access
AZAhmad Mavali Zadeh
Ahmad Mavali Zadeh
Emanuela GattoEmanuela Gatto
Emanuela Gatto
RLRaffaella Lettieri
Raffaella Lettieri
HBHoney Bokharaie
Honey Bokharaie
ACAlice Caravella
Alice Caravella
Michael JeltschMichael Jeltsch
Michael Jeltsch
Vascular Endothelial Growth Factor C (VEGFC) is a promising biological drug, with preclinical studies indicating its potential for treating myocardial infarction, neurodegenerative diseases, and lymphedema, a condition that currently lacks curative treatment. While adenoviral VEGFC gene therapy has progressed to phase II studies, its clinical efficacy is limited by rapid immune inactivation. This study explores lignin nanoparticles (LNPs) as an alternative VEGFC delivery system. Lignin was extracted from grape shoot-derived wood biomass via the organosolv method and used to synthesize LNPs. The resulting particles, with a Z-Average of 143.6 nm, a PDI of 0.126 and a zeta potential of -41 ± 8 mV, were thoroughly characterized using dynamic light scattering and microscopic techniques to evaluate their structural and morphological features. VEGFC loading and release profiles were assessed, showing efficient loading and controlled release capabilities. Stability in plasma and cell viability were evaluated using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay to assess biocompatibility and therapeutic potential. Our data indicate that VEGFC is relatively stable on its own, suggesting that the key advantage of LNPs lies in their ability to modulate the release profile rather than protect the protein from degradation/inactivation.