In the original publication [...].

Head and neck cancer (HNC) is the sixth most common cancer worldwide and remains associated with high mortality. Current therapeutic approaches are often aggressive and lead to functional impairment and disfigurement, reducing quality of life. Minimally invasive and more localized treatment strategies are needed. Gold nanoparticles (AuNPs)-mediated photothermal therapy (PTT) has emerged as a promising approach due to the high photothermal conversion efficiency of AuNPs and their ability to generate localized heat upon near-infrared (NIR) irradiation. This study evaluates the potential of AuNP-mediated PTT for HNC as a proof-of-concept. For this, the physicochemical and optical properties of the AuNPs were characterized. They demonstrated long-term stability, for up to one year, and photothermal stability, maintaining performance throughout four irradiation cycles. The efficacy of AuNPs-mediated PTT was assessed in vivo using two murine models differing in tumor location (neck or flank). Following intratumoral administration of AuNPs and repeated laser irradiation cycles, a clear photothermal effect was observed, associated with increased tumor necrosis and a trend toward reduced tumor progression. Biodistribution studies revealed an accumulation of the AuNPs at the tumor. Importantly, safety assessments showed no significant alterations, indicating the absence of systemic toxicity following treatment. Overall, the developed AuNPs demonstrated long-term physicochemical stability, robust photothermal performance, strong intratumoral accumulation and a favorable safety profile. These findings support the potential of AuNPs-mediated PTT as a localized and minimally invasive therapeutic strategy for HNC. Further studies will include the assessment of the long-term therapeutic outcomes to advance this approach towards clinical translation.

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer lacking estrogen, progesterone, and HER2 receptors. This characteristic limits the effectiveness of hormonal and targeted therapies, and despite advances in chemotherapy (ChT), radiotherapy (RT), surgery, targeted therapy (TT) and immunotherapy (IT), clinical outcomes remain poor, highlighting an urgent need for new therapeutic strategies. The development of advanced nanotechnology-based strategies has opened new avenues for the diagnosis and therapy of TNBC. This review focuses on photothermal therapy (PTT) combined with nanotechnology-based strategies. PTT constitutes an emerging modality for oncological treatment that leverages light irradiation, mostly in the near-infrared (NIR) spectral region, to induce the localized thermal ablation of malignant tissues. When combined with gold nanoparticles (AuNPs), PTT is significantly potentiated. AuNPs have distinctive optical and physicochemical characteristics, rendering them highly effective as multifunctional nanoplatforms. Upon irradiation, AuNPs act as efficient photothermal agents, inducing localized hyperthermia. This thermal effect disrupts cellular homeostasis and initiates a cascade of cell death pathways, including apoptosis and necrosis, culminating in tumor regression. This review describes the latest therapeutic advances of PTT and AuNPs. As this innovative approach progresses toward clinical application, future studies and trials will be crucial in determining its potential for TNBC management and improving patient outcomes.

Sustainable photocatalysis has emerged as a promising approach for environmental remediation by combining efficiency with green chemistry principles. In this study, Ca-TiO2 photocatalytic platforms were developed using cellulose paper as a substrate, calcium sourced directly from eggshell biowaste, and a sustainable microwave-assisted synthesis approach. A novel functionalization of the Whatman paper preserved its structural integrity at temperatures above 200 degrees C, enabling the direct growth of TiO2 nanomaterials on paper substrate without any post-synthesis treatment. Incorporation of bio-derived Ca2+ modified the TiO2 structure, inducing structural defects that included lattice distortions, voids, and surface step sites, modifying optical absorption, and enhancing surface hydroxylation. The resulting Ca-TiO2 paper-based platforms efficiently degraded tetracycline, achieving over 80% removal under solar irradiation in 150 minutes, corresponding to a photodegradation rate 1.3 times higher than that of pure TiO2. Reusability and ecotoxicity tests confirmed their stability and safety for long-term environmental applications. By integrating waste valorization, green synthesis, and structural modifications, this work demonstrates a sustainable and scalable strategy for producing high-performance photocatalytic platforms, aligning with circular economy principles and offering potential solutions for global water pollution challenges.

This study investigates the use of a hybrid approach combining various ratios of sodium borohydride (NaBH4) with hydroethanolic extracts of Salicornia emerici, Sarcocornia fruticosa, and Sarcocornia alpini as reducing agents for AgNPs synthesis. The resulting nanoparticles were confirmed by the presence of a characteristic absorption peak around 400 nm using UV-visible spectroscopy, observed for Sarcocornia-mediated AgNPs at a 1:5 (v/v) extract-to-NaBH4 ratio and at a 1:2 (v/v) ratio for AgNPs synthesized from S. emerici (SE-AgNPs). Furthermore, their size, dispersity and morphology were characterized using dynamic light scattering (DLS) and scanning electron microscopy (SEM), respectively. The nanoparticles displayed variable sizes with broad polydispersity, reflecting heterogeneous nucleation associated with plant-derived metabolites, and predominantly exhibited a cubic shape. Their antibacterial activity against different bacterial strains was evaluated using the broth microdilution method. All formulations inhibited bacterial growth, showing size-independent efficacy. The inhibition of multidrug-resistant bacteria Enterococcus faecalis was particularly noteworthy, with the strongest efficacy observed in SE-AgNPs at a concentration of 21.9 µg/mL. Taken together, the findings suggest that hybrid synthesis can generate bioactive AgNPs while partially reducing dependence on strong chemical reductants. Future work should focus on improving nanoparticle size control, cytotoxicity assessment, and elucidating the mechanistic pathways underlying their bioactivity.

Melanoma stands as the most aggressive form of skin cancer. The lack of effective and safe therapies has led to the investigation of innovative strategies. The present work validates the in vitro and in vivo antimelanoma activity of new copper complexes of 8-hydroxyquinoline (8HQ) derivatives in free or liposomal forms. Firstly, the cytotoxic properties of several copper-based complexes were screened towards human (A375) and murine (B16F10) melanoma cell lines and human dermal fibroblasts or keratinocytes (HaCaT) cell lines. All the complexes presented lower IC50 values (<20 μM) than dacarbazine (DTIC) and temozolomide (TMZ), the positive controls (>80 μM). Aiming to solve low specificity against tumor cells and enhance its targetability to affected sites three metal-based complexes were selected, based on their antiproliferative properties, and incorporated in long blood circulating liposomes. One of them, di-2-(((2-morpholinoethyl)imino)methyl)quinolin-8-olCopper(II), designated as LCR35, was selected for further studies due to the highest incorporation parameters and cytotoxic properties observed. The antiproliferative activity of LCR35 was preserved after its association to liposomes. Moreover, in B16F10 cells this effect was potentiated. Furthermore, cell cycle analysis studies in A375 and B16F10 cell lines were performed to elucidate the mechanism of action of copper-based complex formulations. A cell cycle arrest at G2/M and G0/G1 phases in A375 and B16F10 cells, respectively, both in free and liposomal forms were observed. To validate the therapeutic potential of LCR35 two murine melanoma models were carried out: subcutaneous and metastatic. Pre-clinical studies demonstrated the high therapeutic effect of LCR35, especially after incorporation in liposomes, compared to control group or animals that received LCR35 Free and DTIC. Overall, in vitro and in vivo studies highlight the potential antimelanoma properties of the copper-based complex, LCR35.

Female cancers, primarily breast, cervical, and ovarian cancers, remain a major public health challenge, with rising incidence and high mortality. Cisplatin has long been a cornerstone of anticancer therapy, yet its clinical use is limited by low selectivity, severe side effects, drug resistance, and relapse. Thus, more effective and selective therapeutic strategies are needed. In this study, we evaluated the cytotoxicity and mechanisms of action of three cisplatin derivatives (C-cisplatin, D-cisplatin, and Ac-cisplatin) and their complexes with generation 2 polyamidoamine (PAMAM G2) dendrimers. All drug-dendrimer complexes were prepared at a 10:1 molar ratio and tested on two cancer cell lines-HeLa (cervical cancer) and MCF-7 (breast cancer)-and one non-cancer human microvascular endothelial cell line (HMEC-1). Complex formation was confirmed by zeta potential measurements. Cytotoxicity was assessed for both free and complexed drugs. To explore potential mechanisms of action, mitochondrial membrane potential and reactive oxygen species (ROS) levels were evaluated. Flow cytometry was then used to determine dominant cell-death pathways. The complexes demonstrated cytotoxicity comparable to or greater than cisplatin and showed improved selectivity toward cancer cells. Among them, D-cisplatin complexed with PAMAM G2 was the most promising candidate, exhibiting the highest selectivity toward HeLa cells.

Melanoma is the most aggressive type of skin cancer and recently approved drugs are often associated with resistance and significant adverse effects. Therefore, the design of more effective and safe options remains imperative. Photothermal therapy (PTT) using gold nanoparticles (AuNPs) presents a promising and innovative approach. In this work, the efficacy of combining a previously optimized formulation of AuNPs coated with a mixture of hyaluronic and oleic acids (HAOA-AuNPs) with near-infrared (NIR) laser irradiation in melanoma cell lines was explored. Coated and uncoated AuNPs formulations were characterized in physicochemical, morphological and elemental terms. Next, the cellular uptake efficiency as well as antiproliferative activity of the combination of each formulation with laser irradiation was evaluated. Subsequently, HAOA-AuNPs were selected to assess the underlying mechanism of combined therapy by cell cycle and Annexin V/PI assays. An in vivo syngeneic murine melanoma model was also conducted. In vitro studies demonstrated that 24 h after incubation and in the absence of laser, HAOA-AuNPs did not exhibit cytotoxic effects on the melanoma cell lines tested, similar to the laser alone. On the contrary, the combination therapy resulted in a large reduction in cell viability. Furthermore, it has been shown to promote S-phase cell cycle arrest and increase in the percentage of late apoptotic cells. Finally, the in vivo proof-of-concept showed that the intratumoral administration of HAOA-AuNPs followed by three laser irradiations impaired tumor progression. Collectively, AuNP-based PTT holds significant potential to improve treatment efficacy and safety, offering a versatile and potent tool against cancer.

Pharmaceutical substances are found in soils and water supplies and pose a significant risk to the ecosystem. Solar light-driven photocatalysis with titanium dioxide (TiO2) nanophotocatalysts is widely explored for degrading...

Cellulose and its derivatives are increasingly explored in biomedical applications due to their biocompatibility, biodegradability, and mechanical performance. In regenerative medicine, aerogel scaffolds with tunable morphology and composition are highly valued for their ability to support tissue regeneration. Three-dimensional (3D) printing offers an effective method to fabricate aerogels with hierarchical pore structures, comprising interconnected macropores and mesopores, that are crucial for tissue engineering. For clinical use, 3D printing should ensure the structural integrity of printed structures and achieve a printing resolution that allows for customization. In this work, the X-aerogel technology, implemented via polyurea cross-linking, was applied to 3D-printed cellulose structures, thereby expanding the potential applications of both technologies. Specifically, 3D-printed methylcellulose (MC) and MC doped with bacterial cellulose nanofiber (MCBCf) gels were cross-linked with an aliphatic polyurea, yielding, after supercritical drying, the corresponding (X-MC and X-MCBCf) aerogels. Elaborate characterization with ATR-FTIR, XPS, ToF-SIMS, N2 porosimetry, He pycnometry, and SEM confirmed the formation of polyurea on the biopolymer framework, reinforcing the structure and improving the mechanical properties without altering the morphology or textural characteristics of the materials. A significant outcome of cross-linking with polyurea is the long-term stability of X-MC and X-MCBCf aerogels in water, in contrast to their native counterparts, and their capacity to absorb water up to 1800% w/w within only 2 h. Preliminary biological evaluation of the materials, including in vitro (cell compatibility, hemolytic activity), in ovo (HET-CAM), and in vivo (A. salina model) tests, showed good cell viability, blood compatibility, and safety for living organisms. From a fundamental materials perspective, the most important finding of this work is the disproportionally high stability of X-MC and X-MCBCf in physiological environments, achieved with only a minimal (almost undetectable) amount of cross-linking polyurea. From an application standpoint, the findings of this study, collectively, position these aerogels as sustainable and promising candidates for tissue engineering scaffolds.

Gold nanoparticle (AuNP)-mediated photothermal therapy (PTT) has emerged as a promising approach for cancer treatment, offering high precision, minimal invasiveness, and selective tumor ablation through localized hyperthermia. This review explores the fundamental principles of AuNP-mediated PTT, including the design of AuNPs, synthesis strategies, and surface modifications that enhance their biocompatibility and targeting efficiency. Additionally, the integration of AuNPs with other therapeutic modalities is also discussed, such as chemotherapy, radiotherapy, and immunotherapy, to achieve synergistic treatment outcomes. The theragnostic potential of AuNPs, combining diagnostic imaging with therapeutic applications, is also highlighted, emphasizing their role in personalized medicine. But, despite significant advancements, challenges such as biodistribution, long-term safety, and regulatory approval remain key barriers to clinical translation. Ongoing research is expected to refine AuNP-based PTT, paving the way for its widespread clinical application in cancer treatment.

Melanoma is the most aggressive skin cancer and, despite therapeutic advances in recent years, it continues to be associated with the highest mortality rates. Thus, the development of more effective and safer treatment options remain imperative. In this context, and driven by the discovery of the antineoplastic properties and consequent clinical approval of cisplatin, metal-based complexes have gained increasing attention. In this work, previously synthesized vanadium and nickel-based complexes which exhibited cytotoxic activity towards melanoma cell lines in their free form, were incorporated into liposomes to improve solubility and enhance tumor cell selectivity. Nickel-based nanoformulations showed higher loading capacity than the vanadium complex and were therefore selected for further studies. The optimized nickel lipid nanoformulation was tested in vitro regarding antiproliferative properties and cellular mechanism of action in B16F10 and A375 melanoma cells. Lastly, the therapeutic potential and the biodistribution profile were also evaluated in an in vivo syngeneic murine melanoma model. In vitro studies demonstrated that 24 and 48 h after incubation in melanoma cell lines, the nickel-based complex retained its antiproliferative activity following association with liposomes. Furthermore, the liposomal formulation promoted cell cycle arrest in G2/M phase in both cell lines, while hemolytic assays demonstrated its safety for intravenous administration. Finally, in vivo proof of concept studies confirmed that both the free and liposomal forms of the nickel-based complex significantly impaired tumor progression achieving effects comparable to the positive control 5-Fluorouracil, despite the latter being administered at a four-fold higher dose. Moreover, biodistribution studies revealed that labelled liposomes accumulated and persisted at tumor sites, thus correlating with the observed therapeutic effects. Overall, the safety and efficacy of this strategy highlight its strong potential for melanoma management.

Background: Skin diseases of inflammatory origin, such as atopic dermatitis, psoriasis and acne, have a substantial prevalence in the world population. Natural products are particularly important at a topical level. Essential oils are examples of natural products and thyme in particular has been used for medicinal purposes due to its biological properties. Objectives: The aim of present work was to study the anti-inflammatory potential of Thymus mastichina essential oil, focusing on purified terpene-rich fractions. whose major compounds were thymol and linalool, eucalyptol and α-terpineol, and γ-terpinene and terpinolene, respectively. Additionally, a phytocannabinoid formulation containing cannabidiol (CBD) and cannabigerol (CBG) was evaluated to explore potential synergistic effects. Methods: Thymus mastichina essential oil was extracted and purified to obtain terpene-enriched fractions, which were used to develop three distinct formulations. These were screened for antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and assessed for cytotoxicity in HaCaT human keratinocytes. Anti-inflammatory potential was evaluated via gene expression. Selected thyme formulations—alone or in combination with CBD/CBG—were also tested in vivo using a mouse model of acute skin inflammation. Results: The antioxidant activity of the three formulations showed a reduction in DPPH radicals. In addition, the formulations demonstrated to be safe in vitro in the human keratinocyte cell model HaCaT. Under PMA-induced inflammatory stress, the fractions modulated-inflammatory gene expression to varying degrees While terpene fractions alone showed moderate activity, their combination with CBD/CBG enhanced the anti-inflammatory response. In vivo, the gel formulations reduced oedema in a mouse model of acute inflammation. Conclusions: The data support the safe and effective use of Thymus mastichina-derived terpene fractions for topical anti-inflammatory applications. The synergistic effect observed with CBD and CBG suggests that combining essential oil terpenes with phytocannabinoids may offer a novel therapeutic strategy for managing inflammatory skin disorders.

We report the synthesis and characterization of five novel metal complexes. Three of them are vanadium complexes with the general formula [VO(Ln)2], where Ln are Schiff bases derived from the condensation of 2-carbaldehyde-8-hydroxyquinoline with either 4-(2-aminoethyl)morpholine (L1), 3-morpholinopropylamine (L2) or 1-(2-aminoethyl)piperidine (L3). The two other metal complexes are [Ni(L1)2] and [Fe(L1)2]Cl. They were characterized by analytical, spectroscopic (Fourier transform infrared, UV-visible absorption), and mass spectrometric techniques as well as by single-crystal X-ray diffraction (for all [VO(Ln)2] complexes and [Ni(L1)2]). While, in the crystal structure, the V(IV)O complexes show distorted square–pyramidal geometry with the ligands bound as bidentate through quinolate NO donors, the Ni(II) complex shows octahedral geometry with two ligand molecules coordinated through NNO donors. Stability studies in aqueous media revealed that the vanadium complexes are not stable, undergoing oxidation to VO2(L), which was corroborated by 51V NMR and MS. This behavior is also observed in organic media, though at a significantly slower rate. The Ni complex exhibited small spectral changes over time in aqueous media. Nonetheless, all compounds show enhanced stability in the presence of bovine serum albumin (BSA). Fluorescence studies carried out for the Ni(II) and Fe(III) complexes indicate reversible binding to albumin. The cytotoxicity of the L1 metal complexes was assessed on melanoma (B16F10 and A375) and colon cancer (CT-26 and HCT-116) cell lines, with 5-fluorouracil (5-FU) as a reference drug. The V- and Ni complexes showed the lowest IC50 values (<10 μM) in either A375 or HCT-116 cells after 48 h of incubation, while the Fe(III) complex presented minimal antiproliferative effects. The complexes were generally more cytotoxic to human than murine cancer cells. Synergistic in vitro studies with 5-FU revealed antagonism in most cases, except in A375 cells, where an additive effect was observed for the combination with the V-complex. Overall, these compounds show promising potential for cancer treatment, mostly for melanoma.

The concept “we are what we eat” is gaining increasing relevance as diet-related diseases and comorbidities continue to rise, while consumers place greater emphasis on healthy lifestyles and acknowledge the pivotal role of nutrition in disease prevention. Among dietary components, omega-3 (ω-3) and omega-6 (ω-6) polyunsaturated fatty acids stand out for their broad spectrum of health benefits. This review explores their potential roles in reducing triglyceride levels, delaying the onset of neurodegenerative disorders such as Alzheimer’s and Parkinson’s diseases, preventing depression, supporting infant brain development, modulating inflammatory processes, and contributing to cancer prevention. The mechanisms of action of these fatty acids are discussed, along with their potential adverse effects—particularly the risk of interactions with anticoagulant medications, which require cautious use. While ω-3 fatty acids are widely recognized for their anti-inflammatory properties, ω-6 fatty acids exhibit both pro- and anti-inflammatory effects, highlighting the importance of achieving a balanced intake. The recommended ω-6:ω-3 ratio, ideally between 4:1 and 1:1, is emphasized as a key element in promoting informed dietary choices. This review also discusses current legislation framework on food supplements, with a focus on challenges such as the lack of stringent regulation regarding supplement content. These gaps underline the need for improved nutritional literacy and stronger regulatory oversight. Ultimately, this review emphasizes the imperative for evidence-based dietary fat recommendations, integrative public health education strategies, the revision and standardization of nutritional guidelines, and the enforcement of robust regulatory frameworks and quality-control protocols across the food supplement industry.

Background/Objectives: Head and neck cancer (HNC) is the sixth most common cancer worldwide, with a high mortality, particularly from head and neck squamous cell carcinoma (HNSCC). Although some therapeutic strategies are available, they might cause severe side effects. For example, surgery may result in disfigurement and functional loss, severely impacting the patient’s quality of life. Thus, minimally invasive and more effective alternatives are needed. Gold nanoparticle (AuNP)-mediated photothermal therapy (PTT) is a promising approach for HNC, which relies on AuNP photothermal efficiency and tumor localization. This study aimed to synthesize and characterize AuNPs, evaluate their safety without laser activation, and assess their efficacy with laser activation. Methods and Results: Their physicochemical and photostability over three months and sterility were confirmed. In vitro safety was tested using human non-cancerous and HNC cell lines, while in vivo biocompatibility was evaluated in the hen’s egg chorioallantoic membrane (CAM) model, with no adverse effects observed. Upon laser activation, AuNPs reduced HNC cell viability by 50–70%, including HNSCC lines. In vivo biodistribution studies showed that AuNPs remained at the injection site for up to one month without toxicity. Conclusions: Overall, the developed AuNP formulation demonstrates stability, biocompatibility, and prolonged local retention, key attributes for effective and targeted PTT. These findings support the potential of AuNP-mediated photothermal therapy as a promising treatment modality for HNC, although further preclinical and clinical studies are needed to optimize treatment parameters.

Marine invasive species pose significant ecological, economic, and social challenges, disrupting native ecosystems, outcompeting local species and altering biodiversity. The spread of these species is largely driven by global trade, shipping, and climate change, which allow non-native species to establish themselves in new environments. Current management strategies, including early detection, rapid response, and biosecurity measures, have had some success, but the complexity and scale of the problem require continuous monitoring. This review explores the possibility of using some marine invasive species as skincare ingredients and explores the Azorean islands as a case study for the valorization of biomass. Additionally, this review addresses legislative barriers that delay the development of sustainable cosmetic markets from invasive species, highlighting the regulatory landscape as a critical area. It concludes that marine invasive species present a regional and global problem that requires regional and global solutions. Such solutions strongly need to address environmental impacts and net socioeconomic benefits, but such solutions must also consider all regional differences, technical capacities and financial resources available. Thus, as a future perspective, strategies should emphasize the need for international collaboration and the development of more effective policies to prevent the spread of invasive species. There is still much work to be completed. By working together, the biodiversity for future generations will be better monitored and explored.

AimsColorectal cancer is the third most frequent type of cancer and the second leading cause of cancer-related deaths worldwide. The majority of cases are diagnosed at a later stage, leading to the need for more aggressive treatments such as chemotherapy. 5-Fluorouracil (5-FU), known for its high cytotoxic properties has emerged as a chemotherapeutic agent. However, it presents several drawbacks such as lack of specificity and short half-life. To reduce these drawbacks, several strategies have been designed namely chemical modification or association to drug delivery systems.Materials and methodsCurrent research was focused on the design, physicochemical characterization and in vitro evaluation of a lipid-based system loaded with 5-FU. Furthermore, aiming to maximize preferential targeting and release at tumour sites, a hybrid lipid-based system, combining both therapeutic and magnetic properties was developed and validated. For this purpose, liposomes co-loaded with 5-FU and iron oxide (II, III) nanoparticles were accomplished.Key findingsThe characterization of the developed nanoformulation was performed in terms of incorporation parameters, mean size and surface charge. In vitro studies assessed in a murine colon cancer cell line confirmed that 5-FU antiproliferative activity was preserved after incorporation in liposomes. In same model, iron oxide (II, III) nanoparticles did not exhibit cytotoxic properties. Additionally, the presence of these nanoparticles was shown to confer magnetic properties to the liposomes, allowing them to respond to external magnetic fields.SignificanceOverall, a lipid nanosystem loading a chemotherapeutic agent displaying magnetic characteristics was successfully designed and physicochemically characterized, for further in vivo applications.

Gold nanoparticles (AuNPs)-mediated Photothermal Therapy (PTT) is a minimally-invasive therapeutic approach that uses AuNPs to convert light into heat, leading to the thermal ablation of tumors. Thus, the efficacy of this strategy strongly relies on the photothermal conversion potential of AuNPs. The ability to convert light into heat can be enhanced by tuning the physicochemical and optical properties of AuNPs. This can be achieved by changing the conditions of AuNP's synthesis, such as the order of addition of reagents. The present work entails to explore how varying the order of reagents addition modulates the properties of AuNPs, particularly enhancing the photothermal conversion potential of the resulting AuNPs and consequently, improving PTT efficacy. For this, eleven different AuNPs' nanoformulations were synthetized following different sequences of addition of reagents. These nanoformulations were characterized regarding their physicochemical properties namely size, surface charge, gold concentration, surface morphology and maximum absorbance wavelength. In addition, their thermal activation profiles were determined in vitro. . Furthermore, the biocompatibility of different nano- formulations was also assessed. Three nanoformulations, with the most favorable photothermal activation profiles (AuNPs 2, 3 and 7), were then selected for preliminary in vitro safety and efficacy assays using a panel of cell lines. These three nanoformulations were deemed safe in vitro at the tested concentrations. At 250 mu M of gold content, and after an incubation period of 4 h, followed by 5 min irradiation with a laser emitting at 808 nm (7.96 W/cm2), 2 ), AuNPs 7 significantly reduced the cell viability of all cancer cell lines tested (MCF-7, HCT-116 and A375) by >= 45 %. However, such cytotoxic effect was not observed for the human keratinocyte cell line (HaCat), thus demonstrating its specificity towards cancer cells. Overall, the results herein presented reinforce that the order of reagents addition is highly important for achieving adequate AuNPs for PTT.