Gallium- and Iron-Pyoverdine Coordination Compounds Investigated by X-ray Photoelectron Spectroscopy and X-ray Absorption Spectroscopy.

Iron is an essential nutrient for nearly all forms of life, although scarcely available due to its poor solubility in nature and complex formation in higher eukaryotes. Microorganisms have evolved a vast array of strategies to acquire iron, the most common being the production of high-affinity iron chelators, termed siderophores. The opportunistic bacterial pathogen Pseudomonas aeruginosa synthesizes and secretes two siderophores, pyoverdine (PVD) and pyochelin (PCH), characterized by very different structural and functional properties. Due to its chemical similarity with Fe(III), Ga(III) interferes with several iron-dependent biological pathways. Both PVD and PCH bind Fe(III) and Ga(III). However, while the Ga-PCH complex is more effective than Ga(III) in inhibiting P. aeruginosa growth, PVD acts as a Ga(III) scavenger and protects bacteria from Ga(III) toxicity. To gain more insight into the different outcomes of the biological paths observed for the Fe(III) and Ga(III)-siderophore complexes, better knowledge is needed of their coordination geometries that directly influence the metal complexes chemical stability. The valence state and coordination geometry of the Ga-PCH and Fe-PCH complexes has recently been investigated in detail; as for PVD complexes, several NMR structural studies of Ga(III)-PVD are reported in the literature, using Ga(III) as a diamagnetic isosteric substitute for Fe(III). In this work, we applied up-to-date spectroscopic techniques as synchrotron-radiation-induced X-ray photoelectron spectroscopy (SR-XPS) and X-ray absorption fine structure (XAFS) spectroscopy coupled with molecular modeling to describe the electronic structure and coordination chemistry of Fe and Ga coordinative sites in PVD metal complexes. These techniques allowed us to unambiguously determine the oxidation state of the coordinative ions and to gather interesting information about the similarities and differences between the two coordination compounds as induced by the different metal.

Effects of topical methotrexate loaded gold nanoparticle in cutaneous inflammatory mouse model.

Gold nanoparticles functionalized with 3-mercapto-1-propansulfonate (AuNPs-3MPS) have been prepared and loaded with Methotrexate (MTX), an immunosuppressive agent used in the systemic treatment of moderate-severe inflammatory diseases. The effects of the AuNPs-3MPS@MTX topically administered in vitro on skin model and in vivo on imiquimod-induced psoriasis-like mice model, have been studied. Clinical response, epidermal thickness, cell proliferation rate and inflammation were tested. AuNPs-3MPS@MTX treated mice showed a decreasing of scaling and erythema score, reduction of epidermal thickness, parakeratosis and hyperkeratosis, compared to AuNPs-3MPS treated mice. Immunohistochemistry analysis staining displayed that Ki67, K6 CD3 and CD8 stainings were reduced in AuNPs-3MPS@MTX treated mice. Blood evaluation showed no differences in blood count and in ALT and AST levels before and after AuNPs-3MPS or AuNPs-3MPS@MTX treatment. Topical AuNPs-3MPS@MTX treatment is able to induce a reduction of keratinocytes hyperproliferation, epidermal thickness and also inflammatory infiltrate in vivo on imiquimod-induced psoriasis like mice model.

The Effect of Postmastectomy Radiation Therapy on Breast Implants: Material Analysis on Silicone and Polyurethane Prosthesis.

INTRODUCTION: The pathogenic mechanism underlying capsular contracture is still unknown. It is certainly a multifactorial process, resulting from human body reaction, biofilm activation, bacteremic seeding, or silicone exposure. The scope of the present article is to investigate the effect of hypofractionated radiotherapy protocol (2.66 Gy × 16 sessions) both on silicone and polyurethane breast implants. METHODS: Silicone implants and polyurethane underwent irradiation according to a hypofractionated radiotherapy protocol for the treatment of breast cancer. After irradiation implant shells underwent mechanical, chemical, and microstructural evaluation by means of tensile testing, infrared spectra in attenuated total reflectance mode, nuclear magnetic resonance, and field emission scanning electron microscopy. RESULTS: At superficial analysis, irradiated silicone samples show several visible secondary and tertiary blebs. Polyurethane implants showed an open cell structure, which closely resembles a sponge. Morphological observation of struts from treated polyurethane sample shows a more compact structure, with significantly shorter and thicker struts compared with untreated sample. The infrared spectra in attenuated total reflectance mode spectra of irradiated and control samples were compared either for silicon and polyurethane samples. In the case of silicone-based membranes, treated and control specimens showed similar bands, with little differences in the treated one. Nuclear magnetic resonance spectra on the fraction soluble in CDCl3 support these observations. Tensile tests on silicone samples showed a softer behavior of the treated ones. Tensile tests on Polyurethane samples showed no significant differences. CONCLUSIONS: Polyurethane implants seem to be more resistant to radiotherapy damage, whereas silicone prosthesis showed more structural, mechanical, and chemical modifications.

Sensitivity to Heavy-Metal Ions of Unfolded Fullerene Quantum Dots.

A novel type of graphene-like quantum dots, synthesized by oxidation and cage-opening of C60 buckminsterfullerene, has been studied as a fluorescent and absorptive probe for heavy-metal ions. The lattice structure of such unfolded fullerene quantum dots (UFQDs) is distinct from that of graphene since it includes both carbon hexagons and pentagons. The basic optical properties, however, are similar to those of regular graphene oxide quantum dots. On the other hand, UFQDs behave quite differently in the presence of heavy-metal ions, in that multiple sensitivity to Cu2+, Pb2+ and As(III) was observed through comparable quenching of the fluorescent emission and different variations of the transmittance spectrum. By dynamic light scattering measurements and transmission electron microscope (TEM) images we confirmed, for the first time in metal sensing, that this response is due to multiple complexation and subsequent aggregation of UFQDs. Nonetheless, the explanation of the distinct behaviour of transmittance in the presence of As(III) and the formation of precipitate with Pb2+ require further studies. These differences, however, also make it possible to discriminate between the three metal ions in view of the implementation of a selective multiple sensor.

Local structure of semicrystalline P3HT films probed by nanofocused coherent X-rays.

The hidden structural properties of semicrystalline polymer films are revealed by nanofocused X-ray scattering studies. X-ray cross-correlation analysis (XCCA) is employed to diffraction patterns from blends of poly(3-hexylthiophene) (P3HT) with gold nanoparticles (AuNPs). Spatially resolved maps of orientational distribution of crystalline domains allow us to distinguish sample regions of predominant face-on morphology, with a continuous transition to edge-on morphology. The average size of crystalline domains was determined to be of the order of 10 nm. As compared to pristine P3HT film, the P3HT/AuNPs blend is characterized by substantial ordering of crystalline domains, which can be induced by Au nanoparticles. The inhomogeneous structure of the polymer film is clearly visualized on the spatially resolved nanoscale 2D maps obtained using XCCA. Our results suggest that the observed changes of the polymer matrix within crystalline regions can be attributed to nanoconfinement in the presence of gold nanoparticles.

Biochar/Biopolymer Composites for Potential In Situ Groundwater Remediation.

This study explores the use of pine wood biochar (BC) waste gasified at 950 °C as fillers in polymer matrices to create BC@biopolymer composites with perspectives in groundwater remediation. Four biochar samples underwent different sieving and grinding processes and were extensively characterized via UV-Vis, FTIR, and FESEM-EDS, highlighting the fact that that BCs are essentially graphitic in nature with a sponge-like morphology. The grinding process influences the particle size, reducing the specific surface area by about 30% (evaluated by BET). The adsorption performances of raw BC were validated via an adsorption isotherm using trichloroethylene (TCE) as a model contaminant. A selected BC sample was used to produce hydrophilic, stable polymer composites with chitosan (CS), alginate (ALG), potato starch (PST), and sodium carboxymethylcellulose (CMC) via a simple blending approach. Pilot sedimentation tests over 7 days in water identified BC@PST and BC@CMC as the most stable suspensions due to a combination of both hydrogen bonds and physical entrapment, as studied by FTIR. BC@CMC showed optimal distribution and retention properties without clogging in breakthrough tests. The study concludes that biopolymer-based biochar composites with improved stability in aqueous environments hold significant promise for addressing various groundwater pollution challenges.

Electrospray deposition of starch-containing laccase: A green technique for low-cost and eco-friendly biosensors.

Recently a laccase-based biosensors with unprecedented reuse and storage capabilities in the detection of catechol compound has been manufactured using ambient Electrospray Deposition (ESD) technique. These biosensors showed to be reused up to 63 measurements on the same electrode just prepared at room temperature and pressure. In this new work the reasons behind such a high-performance functioning have been investigated by analysing the commercial sample of laccase with different chemical physics methods: Electrophoresis, Fourier Transform Infrared Spectroscopy, X-ray Fluorescence and Nuclear Magnetic Resonance Spectroscopy. The analyses reveal the presence of the starch in the sample and its essential role as stabilizing agent. Indeed, comparing the performance of starch/laccase-based biosensors with starch-free/laccase-based biosensors, both produced via ESD, showed that the starch-free biosensors lost about 40% of their performance after just the first wash. This suggests that the presence of starch in the laccase sample is a key factor in providing the high wash and storage resistance, which are essential for the fabrication of such devices.

A nanostructured composite based on polyaniline and gold nanoparticles: synthesis and gas sensing properties.

Nanostructured composite materials based on polyaniline (PANI) and gold nanoparticles have been prepared by means of an osmosis based method. Several morphologies have been obtained for the pristine nanoPANI and for nanoPANI-Au composite, ranging from amorphous to sponge-like and spherical shapes. On the basis of this morphological investigation, different materials with high surface area have been selected and tested as chemical interactive materials for room temperature gas and vapor sensing. The resistive sensor devices have been exposed to different vapor organic compounds (VOCs) of interest in the fields of environmental monitoring and biomedical applications, such as toluene, acetic acid, ethanol, methanol, acetonitrile, water, ammonia and nitrogen dioxide. The effect of doping with H2SO4 has been studied for both nanoPANI and nanoPANI-Au samples. In particular, nanoPANI-Au showed sensitivity to ammonia (up to 10 ppm) higher than that to other VOCs or interfering analytes. The facile preparation method and the improved properties achieved for the polyaniline-gold composite materials are significant in the nanomaterials field and have promise for applications in ammonia vapor monitoring.

Peptide-Hydrogel Nanocomposites for Anti-Cancer Drug Delivery.

Cancer is the second leading cause of death globally, but conventional anticancer drugs have side effects, mainly due to their non-specific distribution in the body in both cancerous and healthy cells. To address this relevant issue and improve the efficiency of anticancer drugs, increasing attention is being devoted to hydrogel drug-delivery systems for different kinds of cancer treatment due to their high biocompatibility and stability, low side effects, and ease of modifications. To improve the therapeutic efficiency and provide multi-functionality, different types of nanoparticles (NPs) can be incorporated within the hydrogels to form smart hydrogel nanocomposites, benefiting the advantages of both counterparts and suitable for advanced anticancer applications. Despite many papers on non-peptide hydrogel nanocomposites, there is limited knowledge about peptide-based nanocomposites, specifically in anti-cancer drug delivery. The aim of this short but comprehensive review is, therefore, to focus attention on the synergies resulting from the combination of NPs with peptide-based hydrogels. This review, which includes a survey of recent advances in this kind of material, does not aim to be an exhaustive review of hydrogel technology, but it instead highlights recent noteworthy publications and discusses novel perspectives to provide valuable insights into the promising synergic combination of peptide hydrogels and NPs for the design of novel anticancer drug delivery systems.

Hybrid AuNPs-3MPS-MTX nanosystem and its evaluation for treating cervical cancer and melanoma.

This research presents an evaluation of a hybrid material based on gold nanoparticles (AuNPs), stabilized with the thiol 3-mercapto-propanesulfonate (3MPS) and loaded with the methotrexate drug (MTX). The AuNPs-3MPS-MTX nanosystem was tested for the treatment of cervical cancer and melanoma, using the B16-F10 melanoma and HeLa cell lines. The tests performed on cell cultures assessed the efficiency of the studied nanosystem on tumor cells, as well as its toxicology.

Preparation of Hydrogel Composites Using a Sustainable Approach for In Situ Silver Nanoparticles Formation.

The recognized antibacterial properties of silver nanoparticles (AgNPs) characterize them as attractive nanomaterials for developing new bioactive materials less prone to the development of antibiotic resistance. In this work, we developed new composites based on self-assembling Fmoc-Phe3 peptide hydrogels impregnated with in situ prepared AgNPs. Different methodologies, from traditional to innovative and eco-sustainable, were compared. The obtained composites were characterized from a hydrodynamic, structural, and morphological point of view, using different techniques such as DLS, SEM, and rheological measurements to evaluate how the choice of the reducing agent determines the characteristics of AgNPs and how their presence within the hydrogel affects their structure and properties. Moreover, the antibacterial properties of these composites were tested against S. aureus, a major human pathogen responsible for a wide range of clinical infections. Results demonstrated that the hydrogel composites containing AgNPs (hgel@AgNPs) could represent promising biomaterials for treating S. aureus-related infections.

Surface modification of TiO2 nanoparticles with organic molecules and their biological applications.

In recent years, titanium(IV) dioxide nanoparticles (TiO2NPs) have shown promising potential in various biological applications such as antimicrobials, drug delivery, photodynamic therapy, biosensors, and tissue engineering. For employing TiO2NPs in these fields, their nanosurface must be coated or conjugated with organic and/or inorganic agents. This modification can improve their stability, photochemical properties, biocompatibility, and even surface area for further conjugation with other molecules such as drugs, targeting molecules, polymers, etc. This review describes the organic-based modification of TiO2NPs and their potential applications in the mentioned biological fields. In the first part of this review, around 75 recent publications (2017-2022) are mentioned on the common TiO2NP modifiers including organosilanes, polymers, small molecules, and hydrogels, which improve the photochemical features of TiO2NPs. In the second part of this review, we presented 149 recent papers (2020-2022) about the use of modified TiO2NPs in biological applications, in which specific bioactive modifiers are introduced in this part with their advantages. In this review, the following information is presented: (1) the common organic modifiers for TiO2NPs, (2) biologically important modifiers and their benefits, and (3) recent publications on biological studies on the modified TiO2NPs with their achievements. This review shows the paramount significance of the organic-based modification of TiO2NPs to enhance their biological effectiveness, paving the way toward the development of advanced TiO2-based nanomaterials in nanomedicine.

Teratogenic effects of environmental concentration of plastic particles on freshwater organisms.

Given the widespread presence of plastics, especially in micro- and nanoscale sizes, in freshwater systems, it is crucial to identify a suitable model organism for assessing the potential toxic and teratogenic effects of exposure to plastic particles. Until now, the early life stage of freshwater organisms and the regeneration capacity in relation to plastic particles exposure is a still poorly investigated topic. In this study, we examine the teratogenic effect on diatom Cocconeis placentula and cnidarian Hydra vulgaris under controlled exposure conditions of poly(styrene-co-methyl methacrylate) (P(S-co-MMA)) particles. Significant effects were observed at the lowest concentrations (0.1 µg/L). A significant increase in the teratological frequency in C. placentula and a significant decrease in the regeneration rate in H. vulgaris were found at the lowest concentration. The delay in hydra regeneration impaired the feeding capacity and tentacles reactivity at 96 h of exposure. No effects on diatom growth were observed upon exposure to P(S-co-MMA) particles (0.1, 1, 100, 10,000 µg/L) for 28 days and these findings agree with other studies investigating algal growth. The application of the Teratogenic Risk Index, modified for diatoms, highlighted a moderate risk for the lowest concentration evaluating C. placentula and low risk at the lowest and the highest concentrations considering H. vulgaris. This study suggests the importance of testing organisms belonging to different trophic levels as diverse teratogenic effects can be found and the need to evaluate environmentally relevant concentrations of plastic particles.

Self-Assembling Peptide-Based Magnetogels for the Removal of Heavy Metals from Water.

In this study, we present the synthesis of a novel peptide-based magnetogel obtained through the encapsulation of γ-Fe2O3-polyacrylic acid (PAA) nanoparticles (γ-Fe2O3NPs) into a hydrogel matrix, used for enhancing the ability of the hydrogel to remove Cr(III), Co(II), and Ni(II) pollutants from water. Fmoc-Phe (Fluorenylmethoxycarbonyl-Phenylalanine) and diphenylalanine (Phe2) were used as starting reagents for the hydrogelator (Fmoc-Phe3) synthesis via an enzymatic method. The PAA-coated magnetic nanoparticles were synthesized in a separate step, using the co-precipitation method, and encapsulated into the peptide-based hydrogel. The resulting organic/inorganic hybrid system (γ-Fe2O3NPs-peptide) was characterized with different techniques, including FT-IR, Raman, UV-Vis, DLS, ζ-potential, XPS, FESEM-EDS, swelling ability tests, and rheology. Regarding the application in heavy metals removal from aqueous solutions, the behavior of the obtained magnetogel was compared to its precursors and the effect of the magnetic field was assessed. Four different systems were studied for the separation of heavy metal ions from aqueous solutions, including (1) γ-Fe2O3NPs stabilized with PAA, (γ-Fe2O3NPs); (2) Fmoc-Phe3 hydrogel (HG); (3) γ-Fe2O3NPs embedded in peptide magnetogel (γ-Fe2O3NPs@HG); and (4) γ-Fe2O3NPs@HG in the presence of an external magnetic field. To quantify the removal efficiency of these four model systems, the UV-Vis technique was employed as a fast, cheap, and versatile method. The results demonstrate that both Fmoc-Phe3 hydrogel and γ-Fe2O3NPs peptide magnetogel can efficiently remove all the tested pollutants from water. Interestingly, due to the presence of magnetic γ-Fe2O3NPs inside the hydrogel, the removal efficiency can be enhanced by applying an external magnetic field. The proposed magnetogel represents a smart multifunctional nanosystem with improved absorption efficiency and synergic effect upon applying an external magnetic field. These results are promising for potential environmental applications of γ-Fe2O3NPs-peptide magnetogels to the removal of pollutants from aqueous media.

Biosynthesis of Peptide Hydrogel-Titania Nanoparticle Composites with Antibacterial Properties.

The photoantibacterial properties of titania nanoparticles (TiO2NPs) are attracting much interest, but the separation of their suspension limits their application. In this study, the encapsulation of commercial TiO2NPs within self-assembling tripeptide hydrogels to form hgel-TiO2NP composites with significant photoantibacterial properties is reported. The Fmoc-Phe3 hydrogelator was synthesized via an enzymatic method. The resulting composite was characterized with DLS, ζ-potential, SAXS, FESEM-EDS and rheological measurements. Two different concentrations of TiO2NPs were used. The results showed that, by increasing the TiO2NP quantity from 5 to 10 mg, the value of the elastic modulus doubled, while the swelling ratio decreased from 63.6 to 45.5%. The antimicrobial efficacy of hgel-TiO2NPs was tested against a laboratory Staphylococcus aureus (S. aureus) strain and two methicillin-resistant S. aureus (MRSA) clinical isolates. Results highlighted a concentration-dependent superior antibacterial activity of hgel-TiO2NPs over TiO2NPs in the dark and after UV photoactivation. Notably, UV light exposure substantially increased the biocidal action of hgel-TiO2NPs compared to TiO2NPs. Surprisingly, in the absence of UV light, both composites significantly increased S. aureus growth relative to control groups. These findings support the role of hgel-TiO2NPs as promising biocidal agents in clinical and sanitation contexts. However, they also signal concerns about TiO2NP exposure influencing S. aureus virulence.

Gold Nanorods as Radiopharmaceutical Carriers: Preparation and Preliminary Radiobiological In Vitro Tests.

Low-energy electrons (Auger electrons) can be produced via the interaction of photons with gold atoms in gold nanorods (AuNRs). These electrons are similar to those emitted during the decay of technetium-99m (99mTc), a radioactive nuclide widely used for diagnostics in nuclear medicine. Auger and internal conversion (IC) electron emitters appropriately targeted to the DNA of tumors cells may, therefore, represent a new radiotherapeutic approach. 99mTc radiopharmaceuticals, which are used for diagnosis, could indeed be used in theragnostic fields when loaded on AuNRs and delivered to a tumor site. This work aims to provide a proof of concept (i) to evaluate AuNRs as carriers of 99mTc-based radiopharmaceuticals, and (ii) to evaluate the efficacy of Auger electrons emitted by photon-irradiated AuNRs in inducing radio-induced damage in T98G cells, thus mimicking the effect of Auger electrons emitted during the decay of 99mTc used in clinical settings. Data are presented on AuNRs' chemical characterization (with an aspect ratio of 3.2 and Surface Plasmon Resonance bands at 520 and 680 nm) and the loading of pharmaceuticals (after 99mTc decay) on their surface. Spectroscopic characterizations, such as UV-Vis and synchrotron radiation-induced X-ray photoelectron (SR-XPS) spectroscopies, were performed to investigate the drug-AuNR interaction. Finally, preliminary radiobiological data on cell killing with AuNRs are presented.

Thiol functionalised gold nanoparticles loaded with methotrexate for cancer treatment: From synthesis to in vitro studies on neuroblastoma cell lines.

HYPOTHESIS: Colloidal gold nanoparticles (AuNPs) functionalised with hydrophilic thiols can be used as drug delivery probes, thanks to their small size and hydrophilic character. AuNPs possess unique properties for their use in nanomedicine, especially in cancer treatment, as diagnostics and therapeutic tools. EXPERIMENTS: Thiol functionalised AuNPs were synthesised and loaded with methotrexate (MTX). Spectroscopic and morphostructural characterisations evidenced the stability of the colloids upon interaction with MTX. Solid state (GISAXS, GIWAXS, FESEM, TEM, FTIR-ATR, XPS) and dispersed phase (UV-Vis, DLS, ζ-potential, NMR, SAXS) experiments allowed to understand structure-properties correlations. The nanoconjugate was tested in vitro (MTT assays) against two neuroblastoma cell lines: SNJKP and IMR5 with overexpressed n-Myc. FINDINGS: Molar drug encapsulation efficiency was optimised to be >70%. A non-covalent interaction between the π system and the carboxylate moiety belonging to MTX and the charged aminic group of one of the thiols was found. The MTX loading slightly decreased the structural order of the system and increased the distance between the AuNPs. Free AuNPs showed no cytotoxicity whereas the AuNPs-MTX nanoconjugate had a more potent effect when compared to free MTX. The active role of AuNPs was evidenced by permeation studies: an improvement on penetration of the drug inside cells was evidenced.

Structural changes of conjugated Pt-containing polymetallaynes exposed to gamma ray radiation doses.

The effect of (60)Co gamma rays irradiation on the polymetallayne [-Pt(PBu(3))-C≡C-C(6)H(4)-C(6)H(4)-C≡C-](n) (Pt-DEBP) of defined chain length corresponding to 10 repeat units, has been studied in detail. The UV-vis absorption spectra of Pt-DEBP have been recorded in solution upon exposure of the polymetallayne at increasing radiation doses in the range up to 90 Gy, with special care to the features related to low doses. Complex modifications of the chemical structure of Pt-DEBP could be accessed through NMR, FTIR, GPC, and XPS characterizations, which support the attack of Cl and H radicals coming from the radiolysis of the solvent, CHCl(3), to the triple C≡C bonds of the backbone, leading to the formation of chlorinated double and single C-C bonds, with a concomitant increase of the molecular weight due to a recombinant effect of oligomer fragments upon irradiation. The presence of vinyl and single chlorinated moieties has been sustained from the simulation of the UV-vis spectra based on theoretical calculations.

Peptide-Based Hydrogels: New Materials for Biosensing and Biomedical Applications.

Peptide-based hydrogels have attracted increasing attention for biological applications and diagnostic research due to their impressive features including biocompatibility and biodegradability, injectability, mechanical stability, high water absorption capacity, and tissue-like elasticity. The aim of this review will be to present an updated report on the advancement of peptide-based hydrogels research activity in recent years in the field of anticancer drug delivery, antimicrobial and wound healing materials, 3D bioprinting and tissue engineering, and vaccines. Additionally, the biosensing applications of this key group of hydrogels will be discussed mainly focusing the attention on cancer detection.

Organoselenium compounds as functionalizing agents for gold nanoparticles in cancer therapy.

Gold nanoparticles (AuNPs) modified with four organoselenium compounds, i.e., 4-selenocyanatoaniline (compound 1), 4,4'-diselanediyldianiline (compound 2), N-(4-selenocyanatophenyl)cinnamamide (compound 3), and N-(3-selenocyanatopropyl)cinnamamide (compound 4), were synthesized following two different approaches: direct conjugation and non-covalent immobilization onto hydrophilic and non-cytotoxic AuNPs functionalized with 3-mercapto-1-propanesulfonate (3MPS). Both free compounds and AuNPs-based systems were characterized via UV-Vis, FTIR NMR, mass spectrometry, and SR-XPS to assess their optical and structural properties. Size and colloidal stability were evaluated by DLS and ζ-potential measurements, whereas morphology at solid-state was evaluated by atomic force (AFM) and scanning electron (FESEM) microscopies. AuNPs synthesized through chemical reduction method in presence of Se-based compounds as functionalizing agents allowed the formation of aggregated NPs with little to no solubility in aqueous media. To improve their hydrophilicity and stability mixed AuNPs-3MPS-1 were synthesized. Besides, Se-loaded AuNPs-3MPS revealed to be the most suitable systems for biological studies in terms of size and colloidal stability. Selenium derivatives and AuNPs were tested in vitro via MTT assay against PC-3 (prostatic adenocarcinoma) and HCT-116 (colorectal carcinoma) cell lines. Compared to free compounds, direct functionalization onto AuNPs with formation of Au-Se covalent bond led to non-cytotoxic systems in the concentration range explored (0-100 µg/mL), whereas immobilization on AuNPs-3MPS improved the cytotoxicity of compounds 1, 3, and 4. Selective anticancer response against HCT-116 cells was obtained by AuNPs-3MPS-1. These results demonstrated that AuNPs can be used as a platform to tune the in vitro biological activity of organoselenium compounds.