Dual-Modal Near-Infrared Organic Nanoparticles: Integrating Mild Hyperthermia Phototherapy with Fluorescence Imaging.

Purpose: Our study seeks to develop dual-modal organic-nanoagents for cancer therapy and real-time fluorescence imaging, followed by their pre-clinical evaluation on a murine model. Integrating NIR molecular imaging with nanotechnology, our aim is to improve outcomes for early-stage cutaneous melanoma by offering more effective and less invasive methods. This approach has the potential to enhance both photothermal therapy (PTT) and Sentinel Lymph Node Biopsy (SLNB) procedures for melanoma patients. Methods: NIR-797-isothiocyanate was encapsulated in poly(D,L-lactide-co-glycolide) acid (PLGA) nanoparticles (NPs) using a two-step protocol, followed by thorough characterization, including assessing loading efficiency, fluorescence stability, and photothermal conversion. Biocompatibility and cellular uptake were tested in vitro on melanoma cells, while PTT assay, with real-time thermal monitoring, was performed in vivo on tumor-bearing mice under irradiation with an 808 nm laser. Finally, ex vivo fluorescence microscopy, histopathological assay, and TEM imaging were performed. Results: Our PLGA NPs, with a diameter of 270 nm, negative charge, and 60% NIR-797 loading efficiency, demonstrated excellent stability and fluorescence properties, as well as efficient light-to-heat conversion. In vitro studies confirmed their biocompatibility and cellular internalization. In vivo experiments demonstrated their efficacy as photothermal agents, inducing mild hyperthermia with temperatures reaching up to 43.8 °C. Ex vivo microscopy of tumor tissue confirmed persistent NIR fluorescence and uniform distribution of the NPs. Histopathological and TEM assays revealed early apoptosis, immune cell response, ultrastructural damage, and intracellular material debris resulting from combined NP treatment and irradiation. Additionally, TEM analyses of irradiated zone margins showed attenuated cellular damage, highlighting the precision and effectiveness of our targeted treatment approach. Conclusion: Specifically tailored for dual-modal NIR functionality, our NPs offer a novel approach in cancer PTT and real-time fluorescence monitoring, signaling a promising avenue toward clinical translation.

Stability and Bioaccessibility of Carotenoids from Sea Buckthorn Pomace Encapsulated in Alginate Hydrogel Beads.

Carotenoids, the natural pigments that confer the bright orange color of sea buckthorn berries, are also associated with several health benefits, such as antioxidant activity and skin and eye protection. Due to their lipophilic nature and localization, carotenoids are largely retained in the sea buckthorn pomace (SBP) resulting from juice production. Carotenoids from SBP (70.03 mg/100 g DW), extracted and characterized by HPLC-PDA, contained zeaxanthin (free and esterified) and beta-carotene as major compounds. The SBP carotenoids-enriched sunflower oil was further encapsulated in Ca-alginate hydrogel beads (98.4% encapsulation efficiency) using ionotropic gelation. The hydrogel beads were characterized by confocal laser scanning microscopy and scanning electron microscopy. Fairly good stability (>64%) of the encapsulated carotenoids in the alginate hydrogel beads during storage (30 days, 4 °C and 25 °C) was found, with zeaxanthin esters being the most stable compounds, for all the experimental conditions. The bioaccessibility of the total carotenoids (INFOGEST protocol) was 42.1 ± 4.6% from hydrated, and, respectively, 40.8 ± 4% from dehydrated SBP alginate hydrogel beads. The addition of yogurt to the dehydrated hydrogel beads had a positive effect on the bioaccessibility of free and esterified zeaxanthin, but not on that of the carotenes. In conclusion, SBP is a valuable source of carotenoids which can be protected by encapsulation in alginate hydrogel beads, thus still retaining a good bioaccessibility.

Sonochemical synthesis, optical properties and DFT studies on novel (N-arylamino)phenothiazinium dyes suitable for fluorescence cells imaging.

Novel (N-arylamino)phenothiazinium dyes containing meta-substituted-arylamine auxochrome units were successfully obtained by applying a sonochemical protocol designed for a more efficient energy usage in the preparation of methylene blue (MB) analogues. Single crystal X-ray diffraction analysis revealed the spatial arrangement in aggregated crystalline state of (N-(meta-bromoaryl)amino)phenothiazinium dye with minor variances induced by the nature of the halogenide counterion (iodide or chloride). The optical UV-vis properties of the novel (N-arylamino)phenothiazinium dyes were comparable to those of the parent MB, with the longest wavelength absorption maxima situated in the visible range (640-680 nm), large molar extinction coefficients (log ε = 4.5-5.1) and weak solvatochromism in polar solvents. Their fluorescence emission in solid state was evidenced by One Photon Excited Fluorescence Lifetime Imaging (OPE-FLIM) and Two Photon Excited Fluorescence Lifetime Imaging (TPE-FLIM) experiments. Theoretical calculations based on Time Dependent-Density Functional Theory (TD-DFT) at B3PW91 and CAM-B3LYP/def2-SV(P) level of theory predicted absorption and fluorescence emission wavelength maxima in reasonable agreement with experimental data. Computational results suggest that the electronic excitations imply a departure from the planar molecular ground state towards geometrically rearranged excited states disfavoring the vibronic couplings due to a high degree of flexibility induced by the conformational motion of the N-arylamino auxochromes. Preliminary studies regarding the dyes' relevance in biological environment indicated lipophilicity (log P octanol/water 0.5-2.3), no aggregation tendency in diluted solutions in the concentration range 10-50 microM and ability for cytoplasmatic staining of D407 human retinal pigment epithelial cells.

An overview of cutaneous squamous cell carcinoma imaging diagnosis methods.

Cutaneous squamous cell carcinoma, a type of non-melanoma skin cancer, is a form of keratinocyte carcinoma that stands as one of the most prevalent cancers, exhibiting a rising frequency. This review provides an overview of the latest literature on imaging methods for diagnosing squamous cell carcinoma (SCC) and actinic keratosis (AK). It discusses the diagnostic criteria, advantages, and disadvantages of various techniques such as dermatoscopy, skin ultrasound (US), in vivo and ex-vivo reflectance confocal microscopy (RCM), and line-field confocal optical coherence tomography (LC-OCT). These methods offer benefits including non-invasiveness, rapidity, comprehensive lesion imaging, and enhanced sensitivity, but face challenges like high costs and the need for specialized expertise. Despite obstacles, the use of these innovative techniques is expected to increase with ongoing technological advancements, improving diagnosis and treatment planning for keratinocyte carcinomas. Standardizing LC-OCT imaging algorithms for AK, Bowen's disease, and SCC remains an area for further research.

Advancing MRI with magnetic nanoparticles: a comprehensive review of translational research and clinical trials.

The nexus of advanced technology and medical therapeutics has ushered in a transformative epoch in contemporary medicine. Within this arena, Magnetic Resonance Imaging (MRI) emerges as a paramount tool, intertwining the advancements of technology with the art of healing. MRI's pivotal role is evident in its broad applicability, spanning from neurological diseases, soft-tissue and tumour characterization, to many more applications. Though already foundational, aspirations remain to further enhance MRI's capabilities. A significant avenue under exploration is the incorporation of innovative nanotechnological contrast agents. Forefront among these are Superparamagnetic Iron Oxide Nanoparticles (SPIONs), recognized for their adaptability and safety profile. SPION's intrinsic malleability allows them to be tailored for improved biocompatibility, while their functionality is further broadened when equipped with specific targeting molecules. Yet, the path to optimization is not devoid of challenges, from renal clearance concerns to potential side effects stemming from iron overload. This review endeavors to map the intricate journey of SPIONs as MRI contrast agents, offering a chronological perspective of their evolution and deployment. We provide an in-depth current outline of the most representative and impactful pre-clinical and clinical studies centered on the integration of SPIONs in MRI, tracing their trajectory from foundational research to contemporary applications.

Correlation between Plasmonic and Thermal Properties of Metallic Nanoparticles.

Here, we investigate the correlation between the heat generated by gold nanoparticles, in particular nanospheres and nanobipyramids, and their plasmonic response manifested by the presence of Localized Surface Plasmon Resonances (LSPRs). Using a tunable laser and a thermal camera, we measure the temperature increase induced by colloidal nanoparticles in an aqueous solution as a function of the excitation wavelength in the optical regime. We demonstrate that the photothermal performances of the nanoparticles are strongly related not only to their plasmonic properties but also to the size and shape of the nanoparticles. The contribution of the longitudinal and transversal modes in gold nanobipyramids is also analyzed in terms of heat generation. These results will guide us to design appropriate nanoparticles to act as efficient heat nanosources.

Imaging Approach in the Diagnostics and Evaluation of the Psoriasis Plaque: A Preliminary Study and Literature Review.

(1) Background: the aim of the study was to demonstrate its usefulness in the field of imaging evaluation of plaque morphology in psoriasis vulgaris, with an emphasis on the use of confocal microscopy and other advanced skin-imaging techniques. (2) Methods: we conducted a prospective study over two years (July 2022-April 2024), on patients diagnosed with moderate or severe psoriasis vulgaris, treated in the dermatology department of our institution. We selected 30 patients, of whom 15 became eligible according to the inclusion and the exclusion criteria. A total of 60 psoriasis plaques were analyzed by dermatoscopy using a Delta 30 dermatoscope and Vidix 4.0 videodermoscope (VD), by cutaneous ultrasound (US) using a high-resolution 20 MHz linear probe, and by confocal microscopy, along with histopathological analysis. (3) Results: the study included fifteen patients with vulgar psoriasis, diagnosed histopathologically, of whom six were women and nine were men, with an average age of 55. Between two and six plaques per patient were selected and a total of sixty psoriasis plaques were analyzed by non-invasive imaging techniques. Twelve lesions were analyzed with ex vivo fluorescence confocal microscopy (FCM), compared to histology. US showed that the hyperechoic band and the lack of damage to the subcutaneous tissue were the most common criteria. The epidermis and dermis were found to be thicker in the area of psoriasis plaques compared to healthy skin. Dermatoscopy showed that the specific aspect of psoriasis plaques localized on the limbs and trunk was a lesion with an erythematous background, with dotted vessels with regular distribution on the surface and covered by white scales with diffuse distribution. The presence of bushy vessels with medium condensation was the most frequently identified pattern on VD. Good correlations were identified between the histological criteria and those obtained through confocal microscopy. (4) Conclusions: the assessment and monitoring of patients with psoriasis vulgaris can be conducted in a more complete and all-encompassing manner by incorporating dermatoscopy, ultrasonography, and confocal microscopy in clinical practice.

Plasmon-enhanced photocatalysis: New horizons in carbon dioxide reduction technologies.

The urgent need for transition to renewable energy is underscored by a nearly 50 % increase in atmospheric carbon dioxide levels over the past century. The combustion of fossil fuels for energy production, transportation, and industrial activities are the main contributors to carbon dioxide emissions in the anthroposphere. Present approaches to reducing carbon emissions are proving inefficient, thereby accentuating the relevance of carbon dioxide photocatalysis in combating climate change - one of the critical issues of public concern. This process uses sunlight to convert carbon dioxide into valuable products, e.g., clean fuels, effectively reducing the carbon footprint and offering a sustainable use of carbon dioxide. In this context, plasmonic nanoparticles such as gold, silver, and copper play a pivotal role due to their proficiency in absorbing a wide range of light spectra, thereby effectively generating the necessary electrons and holes for the degradation of pollutants and surpassing the capabilities of traditional semiconductor catalysts. This review meticulously examines the latest advancements in plasmon-based carbon dioxide photocatalysis, scrutinizing the methodologies, characterizations, and experimental outcomes. The critical evaluation extends to exploring adjustments in the dimensional and morphological aspects of plasmonic nanoparticles, complemented by the incorporation of stabilizing agents, which may offer additional benefits. Furthermore, the review includes a thorough analysis of production rates and quantum yields based on different plasmonic materials and nanoparticle shapes and sizes, enriching the ongoing discourse on effective solutions in the field. Thus, our work emphasizes the pivotal role of plasmon-based photocatalysts in reducing carbon dioxide, investigating both the merits and challenges associated with integrating this emerging technology into climate change mitigation efforts.

Recent advances towards point-of-care devices for fungal detection: Emphasizing the role of plasmonic nanomaterials in current and future technologies.

Fungal infections are a significant global health problem, particularly affecting individuals with weakened immune systems. Moreover, as uncontrolled antibiotic and immunosuppressant use increases continuously, fungal infections have seen a dramatic increase, with some strains developing antibiotic resistance. Traditional approaches to identifying fungal strains often rely on morphological characteristics, thus owning limitations, such as struggles in identifying several strains or distinguishing between fungal strains with similar morphologies. This review explores the multifaceted impact of fungi infections on individuals, healthcare providers, and society, highlighting the often-underestimated economic burden and healthcare implications of these infections. In light of the serious constraints of traditional fungal identification methods, this review discusses the potential of plasmonic nanoparticle-based biosensors for fungal infection identification. These biosensors can enable rapid and precise fungal pathogen detection by exploiting several readout approaches, including various spectroscopic techniques, colorimetric and electrochemical assays, as well as lateral-flow immunoassay methods. Moreover, we report the remarkable impact of plasmonic Lab on a Chip technology and microfluidic devices, as they recently emerged as a class of advanced biosensors. Finally, we provide an overview of smartphone-based Point-of-Care devices and the associated technologies developed for detecting and identifying fungal pathogens.

Portable microfluidic plasmonic chip for fast real-time cardiac troponin I biomarker thermoplasmonic detection.

Acute myocardial infarction is one of the most serious cardiovascular pathologies, impacting patients' long-term outcomes and health systems worldwide. Significant effort is directed toward the development of biosensing technologies, which are able to efficiently and accurately detect an early rise of cardiac troponin levels, the gold standard in detecting myocardial injury. In this context, this work aims to develop a microfluidic plasmonic chip for the fast and accurate real-time detection of the cardiac troponin I biomarker (cTnI) via three complementary detection techniques using portable equipment. Furthermore, the study focuses on providing a better understanding of the thermoplasmonic biosensing mechanism taking advantage of the intrinsic photothermal properties of gold nanoparticles. Specifically, a plasmonic nanoplatform based on immobilized gold nanobipyramids was fabricated, exhibiting optical and thermoplasmonic properties that promote, based on a sandwich-like immunoassay, the "proof-of-concept" multimodal detection of cTnI via localized surface plasmon resonance, surface enhanced Raman spectroscopy and thermoplasmonic effects under simulated conditions. Furthermore, after the integration of the plasmonic nanoplatform in a microfluidic channel, the determination of cTnI in 16 real plasma samples was successfully realized via thermoplasmonic detection. The results are compared with a conventional high-sensitivity enzyme-linked immunosorbent clinical assay (ELISA), showing high sensitivity (75%) and specificity (100%) as well as fast response features (5 minutes). Thus, the proposed portable and miniaturized microfluidic plasmonic chip is successfully validated for clinical applications and transferred to clinical settings for the early diagnosis of cardiac diseases, leading towards the progress of personalized medicine.