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1.
Molecules ; 26(15)2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34361832

RESUMO

In recent times, researchers have aimed for new strategies to combat cancer by the implementation of nanotechnologies in biomedical applications. This work focuses on developing protein-based nanoparticles loaded with a newly synthesized NIR emitting and absorbing phthalocyanine dye, with photodynamic and photothermal properties. More precisely, we synthesized highly reproducible bovine serum albumin-based nanoparticles (75% particle yield) through a two-step protocol and successfully encapsulated the NIR active photosensitizer agent, achieving a good loading efficiency of 91%. Making use of molecular docking simulations, we confirm that the NIR photosensitizer is well protected within the nanoparticles, docked in site I of the albumin molecule. Encouraging results were obtained for our nanoparticles towards biomedical use, thanks to their negatively charged surface (-13.6 ± 0.5 mV) and hydrodynamic diameter (25.06 ± 0.62 nm), favorable for benefitting from the enhanced permeability and retention effect; moreover, the MTT viability assay upholds the good biocompatibility of our NIR active nanoparticles. Finally, upon irradiation with an NIR 785 nm laser, the dual phototherapeutic effect of our NIR fluorescent nanoparticles was highlighted by their excellent light-to-heat conversion performance (photothermal conversion efficiency 20%) and good photothermal and size stability, supporting their further implementation as fluorescent therapeutic agents in biomedical applications.


Assuntos
Indóis/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias Ovarianas/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Soroalbumina Bovina/química , Proliferação de Células , Feminino , Humanos , Indóis/química , Luz , Simulação de Acoplamento Molecular , Nanopartículas/química , Neoplasias Ovarianas/patologia , Fármacos Fotossensibilizantes/química , Espectroscopia de Luz Próxima ao Infravermelho , Células Tumorais Cultivadas
2.
Biomater Sci ; 9(18): 6183-6202, 2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34346411

RESUMO

Among women, ovarian cancer is the fifth most frequent type of cancer, and despite benefiting from current standard treatment plans, 90% of patients relapse in the subsequent 18 months and, eventually, perish. As a result, via embracing nanotechnological advancements in the field of medical science, researchers working in the areas of cancer therapy and imaging are looking for the next breakthrough treatment strategy to ensure lower cancer recurrence rates and improved outcomes for patients. Herein, we design a novel phototheranostic agent with optical features in the biological window of the electromagnetic spectrum via encapsulating a newly synthesized phthalocyanine dye within biocompatible protein nanoparticles, allowing the targeted fluorescence imaging and synergistic dual therapy of ovarian cancer. The nanosized agent displays great biocompatibility and enhanced aqueous biostability and photothermal activity, as well as high reactive-oxygen-species generation efficiency. To achieve the active targeting of the desired malignant tissue and suppress the rapid clearance of the photosensitive agent from the peritoneal cavity, the nanoparticles are biofunctionalized with an anti-folate receptor antibody. A2780 ovarian cancer cells are employed to confirm the improved targeting capabilities and the in vitro cytotoxic efficiency of the theranostic nanoparticles after exposure to a 660 nm LED lamp; upon measurement via MTT and flow cytometry assays, a significant 95% decrease in the total number of viable cells is seen. Additionally, the therapeutic performance of our newly designed nanoparticles was evaluated in vivo, via real-time thermal monitoring and histopathological assays, upon the irradiation of tumour-bearing mice with a 660 nm LED lamp (0.05 W cm-2). Foremost, separately from steady-state fluorescence imaging, we found that, via utilizing FLIM investigations, the differences in fluorescence lifetimes of antibody biofunctionalized and non-functionalized nanoparticles can be correlated to different intracellular localization and internalization pathways of the fluorescent agent, which is relevant for the development of a cutting-edge method for the detection of cancer cells that overexpress folate receptors at their surfaces.


Assuntos
Nanopartículas , Neoplasias Ovarianas , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos , Imagem Óptica , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico , Fototerapia , Medicina de Precisão , Nanomedicina Teranóstica
3.
Phytochemistry ; 189: 112849, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34182200

RESUMO

Anthocyanins (AN), natural compounds daily consumed by humans, have outstanding therapeutical potential if administered topically in melanoma pathology. However, the search for efficient therapy development is still in progress, owing to the lack of complete understanding of the AN intracellular path, once they are uptaken by the cells. This target is constrained by the need for an imaging strategy that would enable their intracellular detection and localization in-situ. In this light, diphenylboric acid 2-aminoethyl (DPBA), a non-fluorescent reagent, was here successfully used to form fluorescent complexes with AN. The AN used are the cyanidin aglycon as a free standard molecule (CY), and the glycosylated compounds, extracted and purified from chokeberry fruits (AE). In solution, it was observed that the fluorescence emission increased by 39% (CY@DPBA), and by 34% (AE@DPBA), which concludes that AN form fluorescent complexes with DPBA (CY@DPBA and AE@DPBA). In addition, using NMR (nuclear magnetic resonance) spectroscopy, and HRMS (high-resolution mass spectrometry) analysis, the structure of the CY@DPBA complex was efficiently elucidated. In-vitro experiments showed that the complexes formed after the treatment proved to be non-toxic on B16-F10 cells. The sub-cellular visualization of all AN was monitored by fluorescence microscopy and flow cytometry, demonstrating detectable signals of the non-metabolized CY and glycosylated CY inside melanoma cells. This study reports that the use of DPBA to image AN intracellularly is a sensitive, non-invasive and successful method that can extend its application in broad fields like drug development or metabolism-associated mechanisms.


Assuntos
Antocianinas , Melanoma Experimental , Animais , Antocianinas/farmacologia , Linhagem Celular Tumoral , Melanoma Experimental/tratamento farmacológico , Camundongos , Camundongos Endogâmicos C57BL , Imagem Óptica
4.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804193

RESUMO

We report here the synthesis and structural characterization of novel cationic (phenothiazinyl)vinyl-pyridinium (PVP) dyes, together with optical (absorption/emission) properties and their potential applicability as fluorescent labels. Convective heating, ultrasound irradiation and mechanochemical synthesis were considered as alternative synthetic methodologies proficient for overcoming drawbacks such as long reaction time, nonsatisfactory yields or solvent requirements in the synthesis of novel dye (E)-1-(3-chloropropyl)-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium bromide 3d and its N-alkyl-2-methylpyridinium precursor 1c. The trans geometry of the newly synthesized (E)-4-(2-(7-bromo-10-ethyl-10H-phenothiazin-3-yl)vinyl)-1-methylpyridin-1-ium iodide 3b and (E)-1-methyl-4-(2-(10-methyl-10H-phenothiazin-3-yl)vinyl)pyridin-1-ium tetrafluoroborate 3a' was confirmed by single crystal X-ray diffraction. A negative solvatochromism of the dyes in polar solvents was highlighted by UV-Vis spectroscopy and explanatory insights were supported by molecular modeling which suggested a better stabilization of the lowest unoccupied molecular orbitals (LUMO). The photostability of the dye 3b was investigated by irradiation at 365 nm in different solvents, while the steady-state and time-resolved fluorescence properties of dye 3b and 3a' in solid state were evaluated under one-photon excitation at 485 nm. The in vitro cytotoxicity of the new PVP dyes on B16-F10 melanoma cells was evaluated by WST-1 assay, while their intracellular localization was assessed by epi-fluorescence conventional microscopy imaging as well as one- and two-photon excited confocal fluorescence lifetime imaging microscopy (FLIM). PVP dyes displayed low cytotoxicity, good internalization inside melanoma cells and intense fluorescence emission inside the B16-F10 murine melanoma cells, making them suitable staining agents for imaging applications.


Assuntos
Corantes Fluorescentes/química , Compostos de Piridínio/química , Coloração e Rotulagem/métodos , Animais , Corantes Fluorescentes/síntese química , Camundongos , Microscopia de Fluorescência , Fenotiazinas/química , Fótons , Compostos de Piridínio/síntese química , Solventes/química , Espectrometria de Fluorescência/métodos
5.
Colloids Surf B Biointerfaces ; 203: 111755, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33862575

RESUMO

Herein, we report the fabrication of a nanotherapeutic platform integrating near-infrared (NIR) imaging with combined therapeutic potential through photodynamic (PDT) and photothermal therapies (PTT) and recognition functionality against ovarian cancer. Owing to its NIR fluorescence, singlet oxygen generation and heating capacity, IR780 iodide is exploited to construct a multifunctional nanosystem for single-wavelength NIR laser imaging-assisted dual-modal phototherapy. We opted for loading IR780 into polymeric Pluronic-F127-chitosan nanoformulation in order to overcome its hydrophobicity and toxicity and to allow functionalization with folic acid. The obtained nanocapsules show temperature-dependent swelling and spectroscopic behavior with favorable size distribution for cellular uptake at physiological temperatures, improved fluorescence properties and good stability. The fabricated nanocapsules can efficiently generate singlet oxygen in solution and are able to produce considerable temperature increase (46 °C) upon NIR laser irradiation. Viability assays on NIH-OVCAR-3 cells confirm the successful biocompatibilization of IR780 by encapsulating in Pluronic and chitosan polymers. NIR fluorescence imaging assays reveal the ability of folic-acid functionalized nanocapsules to serve as intracellular contrast agents and demonstrate their active targeting capacity against folate receptor expressing ovarian cancer cells (NIH-OVCAR-3). Consequently, the targeted nanocapsules show improved NIR laser induced phototherapeutic performance against NIH-OVCAR-3 cells compared to free IR780. We anticipate that this class of nanocapsules holds great promise as theranostic agents for application in image-guided dual PDT-PTT and imaging assisted surgery of ovarian cancer.


Assuntos
Quitosana , Hipertermia Induzida , Nanocápsulas , Neoplasias Ovarianas , Fotoquimioterapia , Apoptose , Linhagem Celular Tumoral , Quitosana/análogos & derivados , Feminino , Ácido Fólico , Humanos , Indóis , Imagem Óptica , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/tratamento farmacológico , Fototerapia
6.
Talanta ; 228: 122242, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33773714

RESUMO

Gold nanoparticles are known to exhibit appealing intrinsic plasmon-modulated photoluminescence (PL) properties which can be explored in various fluorescence-based sensing applications. In this paper, we evaluate the PL of different-sized gold nanospheres (AuNSs) under one-photon excitation (1PE) and develop a sensitive homogeneous immunoassay for the detection of prostate specific antigen (PSA) in colloidal suspension via fluorescence correlation spectroscopy (FCS). The 1PE PL of AuNSs of three different sizes are evaluated in solution phase under excitation at 405 nm via steady-state fluorescence spectroscopy measurements, while FCS analysis emphasizes the feasibility of using 1PE PL properties to monitor their diffusion behavior. Fluorescence lifetime imaging microscopy (FLIM) assays coupled with PL spectral profile analysis performed on single-particles-like structures conform the plasmonic origin of the detected PL and validate their potential of synthesized AuNSs as fluorescent probes in bioimaging and bioassays. Finally, to the best of our knowledge, we provide the first demonstration of the successful use of the 1PE PL of the synthesized AuNSs as probes for the FCS-based one-step label-free sensitive optical detection of PSA biomarker. The approach consisting in monitoring the diffusion of the AuNSs-oligomers induced by the interaction of anti-PSA-conjugated AuNSs with PSA molecules is successfully validated for the detection of PSA levels as low as 4.4 ng/ml in solution. Considering that the development of rapid, efficient and label-free biosensing methods is of continuous interest nowadays, we are confident that our results may have a strong impact on medicine towards more efficient, sensitive and reliable diagnosis.


Assuntos
Nanopartículas Metálicas , Nanosferas , Ouro , Humanos , Masculino , Antígeno Prostático Específico , Espectrometria de Fluorescência
7.
Int J Nanomedicine ; 16: 2147-2171, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33746512

RESUMO

The use of fluorescence imaging technique for visualization, resection and treatment of cancerous tissue, attained plenty of interest once the promise of whole body and deep tissue near-infrared (NIR) imaging emerged. Why is NIR so desired? Contrast agents with optical properties in the NIR spectral range offer an upgrade for the diagnosis and treatment of cancer, by dint of the deep tissue penetration of light in the NIR region of the electromagnetic spectrum, also known as the optical window in biological tissue. Thus, the development of a new generation of NIR emitting and absorbing contrast agents able to overcome the shortcomings of the basic free dye administration is absolutely essential. Several examples of nanoparticles (NPs) have been successfully implemented as carriers for NIR dye molecules to the tumour site owing to their prolonged blood circulation time and enhanced accumulation within the tumour, as well as their increased fluorescence signal relative to free fluorophore emission and active targeting of cancerous cells. Due to their versatile structure, good biocompatibility and capability to efficiently load dyes and bioconjugate with diverse cancer-targeting ligands, the research area of developing protein-based NPs encapsulated or conjugated with NIR dyes is highly promising but still in its infancy. The current review aims to provide an up-to-date overview on the biocompatibility, specific targeting and versatility offered by protein-based NPs loaded with different classes of NIR dyes as next-generation fluorescent agents. Moreover, this study brings to light the newest and most relevant advances involving the state-of-the-art NIR fluorescent agents for the real-time interventional NIR fluorescence imaging of cancer in clinical trials.


Assuntos
Corantes/química , Retroalimentação , Raios Infravermelhos , Nanopartículas/química , Neoplasias/diagnóstico por imagem , Neoplasias/cirurgia , Proteínas/química , Animais , Fluorescência , Humanos
8.
Talanta ; 225: 121960, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33592715

RESUMO

Photoluminescent gold nanoclusters have attracted an extensive research interest in bioimaging and therapeutics due to several distinctive advantages such as high fluorescent photostability, good dispersibility, low toxicity and large Stokes shift. However, a better understanding of the correlation between optical properties in various environments and their uptake by specific cancer cells is still needed. Herein, we developed bovine serum albumin stabilized gold nanoclusters (BSA-AuNCs) with an intrinsic tunable photoluminescence emission in the first biological window. The as-synthetized BSA-AuNCs agents consists in protein polymerized-chains dopped with AuNCs with an average size of 2-3 nm and were found to exhibit relevant properties as high photostability, temperature-dependent and excitation induced tunable red photoluminescence. The photostable BSA-AuNCs were functionalized with folic acid (FA-BSA-AuNCs) in order to achieve for the first time an active targeting of NIH:OVCAR-3 human ovarian adenocarcinoma cells, via AuNCs, towards bioimaging applications. After confirming their biocompatibility up to a concentration of 40 mg/ml, the improved cellular uptake and staining ability of FA-BSA-AuNCs compared to the BSA-AuNCs was validated by conventional wide-field epi-fluorescence microscopy, while the intracellular localization was monitored by confocal fluorescence lifetime imaging microscopy (FLIM). Considering their valuable intrinsic photoluminescent properties, the synthesized FA-BSA-AuNCs hold great promise for direct application in cellular imaging as efficient contrast agents towards early cancer diagnosis and image-guided therapy of cancer.


Assuntos
Nanopartículas Metálicas , Neoplasias Ovarianas , Apoptose , Linhagem Celular Tumoral , Feminino , Ácido Fólico , Ouro , Humanos , Nanopartículas Metálicas/toxicidade , Imagem Óptica , Neoplasias Ovarianas/diagnóstico por imagem
9.
Chemistry ; 27(20): 6112-6130, 2021 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-33284500

RESUMO

The Coronavirus disease 2019 (COVID-19) emergency has demonstrated that the utilization of face masks plays a critical role in limiting the outbreak. Healthcare professionals utilize masks all day long without replacing them very frequently, thus representing a source of cross-infection for patients and themselves. Nanotechnology is a powerful tool with the capability to produce nanomaterials with unique physicochemical and antipathogen properties. Here, how to realize non-disposable and highly comfortable respirators with light-triggered self-disinfection ability by bridging bioactive nanofiber properties and stimuli-responsive nanomaterials is outlined. The visionary road highlighted in this Concept is based on the possibility of developing a new generation of masks based on multifunctional membranes where the presence of nanoclusters and plasmonic nanoparticles arranged in a hierarchical structure enables the realization of a chemically driven and on-demand antipathogen activities. Multilayer electrospun membranes have the ability to dissipate humidity present within the mask, enhancing the wearability and usability. The photothermal disinfected membrane is the core of these 3D printed and reusable masks with moisture pump capability. Personalized face masks with smart nano-assisted destruction of pathogens will bring enormous advantages to the entire global community, especially for front-line personnel, and will open up great opportunities for innovative medical applications.


Assuntos
COVID-19 , Humanos , Máscaras , SARS-CoV-2
10.
Colloids Surf B Biointerfaces ; 194: 111213, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32622254

RESUMO

A great amount of effort is directed towards the progress of cancer treatment approaches aspiring to develop non-invasive, targeted and highly efficient therapies. In this context, Photothermal (PTT) and Photodynamic (PDT) Therapies were proven as promising. This work aims to integrate the therapeutic activities of two near-infrared (NIR) photoactive biomaterials - gold nano-bipyramids (AuBPs) and Indocyanine Green (ICG) - into one single targeted hybrid nanosystem able to operate as dual PTT-PDT agent with higher efficiency compared with each one alone. Firstly, different aspect ratio' AuBPs were systematically investigated in water solution for their intrinsic ability to efficiently generate toxic reactive oxygen species, namely oxygen singlet (1O2), under NIR laser irradiation, as this effect is less investigated in literature. Interestingly, the photodynamic activity of AuBPs measured by monitoring the photooxidation of 9,10-Anthracenediyl-bis(methylene)dimalonic acid (ABDA) - a well-known 1O2 sensor, is important, counting for 30 % decrease in ABDA optical absorbance for the most active AuBPs, well-correlating with the previously determined photothermal conversion efficiency. Furthermore, ICG was successfully grafted onto the Poly-lactic acid (PLA) coating of plasmonic nanoparticles and, consequently, the as-designed fully integrated hybrid nanosystem shows improved PTT-PDT performance in solution. Specifically, by triggering simultaneous PTT-PDT activities, the 1O2 amount is doubled, while the heating monitoring shows higher and faster increase in temperature compared to AuBPs alone. Finally, the efficiency of the combined PTT-PDT therapeutic activity was validated in vitro against B16-F10 cell line by covalent conjugation of the nanosystem with Folic Acid, which ensures the cellular recognition by overexpression of folate receptor.


Assuntos
Melanoma , Fotoquimioterapia , Ouro , Humanos , Verde de Indocianina , Triazenos
11.
Int J Mol Sci ; 21(14)2020 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-32664456

RESUMO

The graphene road in nanomedicine still seems very long and winding because the current knowledge about graphene/cell interactions and the safety issues are not yet sufficiently clarified. Specifically, the impact of graphene exposure on gene expression is a largely unexplored concern. Herein, we investigated the intracellular fate of graphene (G) decorated with cyclodextrins (CD) and loaded with doxorubicin (DOX) and the modulation of genes involved in cancer-associated canonical pathways. Intracellular fate of GCD@DOX, tracked by FLIM, Raman mapping and fluorescence microscopy, evidenced the efficient cellular uptake of GCD@DOX and the presence of DOX in the nucleus, without graphene carrier. The NanoString nCounter™ platform provided evidence for 34 (out of 700) differentially expressed cancer-related genes in HEp-2 cells treated with GCD@DOX (25 µg/mL) compared with untreated cells. Cells treated with GCD alone (25 µg/mL) showed modification for 16 genes. Overall, 14 common genes were differentially expressed in both GCD and GCD@DOX treated cells and 4 of these genes with an opposite trend. The modification of cancer related genes also at sub-cytotoxic G concentration should be taken in consideration for the rational design of safe and effective G-based drug/gene delivery systems. The reliable advantages provided by NanoString® technology, such as sensibility and the direct RNA measurements, could be the cornerstone in this field.


Assuntos
Ciclodextrinas/metabolismo , Doxorrubicina/metabolismo , Expressão Gênica/efeitos dos fármacos , Grafite/metabolismo , Nanoestruturas/administração & dosagem , Neoplasias/metabolismo , Animais , Linhagem Celular , Linhagem Celular Tumoral , Ciclodextrinas/farmacologia , Doxorrubicina/farmacologia , Portadores de Fármacos/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Técnicas de Transferência de Genes , Humanos , Camundongos , Neoplasias/tratamento farmacológico
12.
Molecules ; 25(14)2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32668589

RESUMO

Nowadays, thanks to nanotechnological progress, which itself guides us more and more closely toward not only the efficient design of innovative nanomaterials or nanostructures, but to the improvement of their functionality, we benefit from an important asset in the battle against pathogenic illnesses. Herein, we report a versatile biocompatible plasmonic nanoplatform based on a Whatman paper incorporating positively-charged gold nanospherical particles via the immersion approach. The morphological characterization of the as-engineered-plasmonic paper was examined by SEM (scanning electron microscopy) and HRTEM (high-resolution transmission electron microscopy) investigations, while its surface chemical modification with a synthetic polypeptide, specifically RRWHRWWRR-NH2 (P2), was proved by monitoring the plasmonic response of loaded gold nanospheres and the emission signal of P2 via fluorescence spectroscopy. The as-functionalized plasmonic paper is non-cytotoxic towards BJ fibroblast human cells at bactericidal concentrations. Finally, the antimicrobial activity of the P2-functionalized plasmonic paper on both planktonic bacteria and biofilms was tested against two reference strains: Gram-positive Bacteria, i.e., Staphylococcus aureus and the Gram-negative Bacteria, i.e., Escherichia coli, determining microbial inhibition of up to 100% for planktonic bacteria. In line with the above presented nanoplatform's proper design, followed by their functionalization with active antimicrobial peptides, new roads can be open for determining antibiotic-free treatments against different relevant pathogens.


Assuntos
Antibacterianos , Materiais Biocompatíveis , Escherichia coli/efeitos dos fármacos , Ouro/farmacologia , Nanopartículas Metálicas/química , Peptídeos/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Biofilmes/efeitos dos fármacos , Linhagem Celular , Humanos , Papel
13.
Nanomaterials (Basel) ; 10(6)2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-32471140

RESUMO

Designing innovative (nano)detection platforms, respecting their low-cost and fabrication simplicity, capable to chemically detect multiple target analytes by employing the same engineered device, is still a great challenge in the multiplexed biosensor development. In this scientific context, in the current manuscript, we exploit the low-cost plasmonic calligraphy as a versatile approach to directly draw continuous plasmonic lines on Whatman paper using a regular ballpoint pen successively filled with two different anisotropic nanoparticles shapes (gold bipyramids-AuBPs and gold nanorods-AuNRs) as colloidal inks. After the efficient immobilization of the positively-charged AuBPs and AuNRs onto the paper fibres, proved by Scanning Electron Microscopy (SEM) investigations, the specificity of our as-calligraphed-paper platform is ensured by coating the selected lines with a thin layer of anionic poly(styrene sulfonate) polyelectrolyte, creating, consequently, a well-defined plasmonic array of charge-selective regions. Finally, the functionality of the well-isolated and as-miniaturized active plasmonic array is, subsequently, tested using the anionic Rose-Bengal and cationic Rhodamine 6G target analytes and proved by complementary dual optical "ON/OFF Switch" sensing (i.e. Surface-enhanced Raman Scattering sensing/metal-enhanced fluorescence sensing) onto the same plasmonic line, developing thus a simple multiplexed plasmonic array platform, which could further facilitate the well-desired biomarker detection in complex mixtures.

14.
Int J Mol Sci ; 21(9)2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32365924

RESUMO

We report here the synthetic procedure applied for the preparation of new AB3-type and trans-A2B2 type meso-halogenophenothiazinyl-phenyl-porphyrin derivatives, their metal core complexation and their peripheral modification using Suzuki-Miyaura cross coupling reactions with various (hetero)aryl (phenothiazinyl, 7-formyl-phenothiazinyl, (9-carbazolyl)-phenyl and 4-formyl-phenyl, phenyl) boronic acid derivatives. The meso-phenothiazinyl-phenyl-porphyrin (MPP) dyes family was thus extended by a series of novel phenothiazine-bridged porphyrin-(hetero)aryl dyads characterized by UV-Vis absorption/emission properties typical to the porphyrin chromophore, slightly modulated by increasing the size of peripheral substituents. Three phenothiazine-bridged porphyrin-heteroaryl dyads with fluorescence emission above 655 nm were selected as fluorophores in red spectral region for applications in cellular staining of human ovarian tumors. In vitro experiments of cell metabolic activity displayed a moderate toxicity on human ovarian tumor cell lines (OVCAR-3, cisplatin-sensitive A2780 and cisplatin-resistant A2780cis respectively). Visualization of the stained living cells was performed both by fluorescence microscopy imaging and by fluorescence lifetime imaging under two photon excitation (TPE-FLIM), confirming their cellular uptake and the capability of staining the cell nucleus.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Fenotiazinas/química , Porfirinas/química , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Feminino , Humanos , Microscopia de Fluorescência
15.
Nanotechnology ; 31(31): 315102, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32315999

RESUMO

Nowadays, extensive research is being carried out to find innovative solutions for the development of stable, reproductible, and highly efficient fluorescent contrast agents with the ability of targeting specific cells, which can be further implemented for fluorescent-guided surgery in a real clinical setting. The present study is focused on the development of fluorescent dye-loaded protein nanoparticles (NPs) to overcome the drawbacks of the standard administration of free organic fluorophores, such as cytotoxicity, aqueousinstability, and rapid photo-degradation. Precisely, human serum albumin (HSA) NPs loaded with two different FDA approved dyes, namely indocyanine green (ICG) and fluorescein isothiocyanate (FITC), with a fluorescence response in the near-infrared and visible spectral domains, respectively, have been successfully designed. Even though the diameter of fluorescent HSA NPs is around 30 nm as proven by dynamic light scattering and transmission electron microscopy investigations, they present good loading efficiencies of almost 50% for ICG, and over 30% for FITC and a high particle yield of over 75%. Molecular docking simulations of ICG and FITC within the structure of HSA confirmed that the dyes were loaded inside the NPs, and docked in Site I (subdomain IIA) of the HSA molecule. After the confirmation of their high fluorescence photostability, the NPs were covalently conjugated with folic acid (HSA-FA NPs) in order to bind specifically to the folate receptor alpha (FRα) protein overexpressed on NIH:OVCAR3 ovarian cancer cells. Finally, fluorescence microscopy imaging investigations validate the improved internalization of folate targeted HSA&FITC NPs compared to cells treated with untargeted ones. Furthermore, TEM examinations of the distribution of HSA NPs into the NIH:OVCAR3 cells revealed anincreased number of NP-containing vesicles for the cells treated with HSA-FA NPs, compared to the cells exposed to untargeted HAS NPs, upholding the enhanced cellular uptake through FRα-mediated potocytosis.


Assuntos
Receptor alfa de Estrogênio/metabolismo , Corantes Fluorescentes/química , Ácido Fólico/farmacologia , Neoplasias Ovarianas/metabolismo , Albumina Sérica Humana/química , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Fluoresceína-5-Isotiocianato/química , Ácido Fólico/química , Humanos , Verde de Indocianina/química , Simulação de Acoplamento Molecular , Nanopartículas , Regulação para Cima
16.
ACS Appl Mater Interfaces ; 11(49): 46101-46111, 2019 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-31729219

RESUMO

The theranostic ability of a new fluorescently labeled cationic cyclodextrin-graphene nanoplatform (GCD@Ada-Rhod) was investigated by studying its intracellular trafficking and its ability to deliver plasmid DNA and microRNA. The nanoplatform was synthesized by both covalent and supramolecular approaches, and its chemical structure, morphology, and colloidal behavior were investigated by TGA, TEM, spectroscopic analysis such as UV-vis, fluorescence emission, DLS, and ζ-potential measurements. The cellular internalization of GCD@Ada-Rhod and its perinuclear localization were assessed by FLIM, Raman imaging, and fluorescence microscopy. Biological experiments with pCMS-EGFP and miRNA-15a evidenced the excellent capability of GCD@Ada-Rhod to deliver both pDNA and microRNA without significant cytotoxicity. The biological results evidenced an unforeseen caveolae-mediated endocytosis internalization pathway (generally expected for particles <200 nm), despite the fact that the GCD@Ada-Rhod size is about 400 nm (by DLS and TEM data). We supposed that the internalization pathway was driven by physical-chemical features of GCD@Ada-Rhod, and the caveolae-mediated uptake enhanced the transfection efficiency, avoiding the lysosomal acid degradation. The cellular effects of internalized miRNA-15a on the oncogene protein BCL-2 were investigated at two different concentrations (N/P = 10 and 5), and a reduction of the BCL-2 level was detected at a low concentration (i.e., N/P = 10). miRNA-15a is considered an ideal cancer therapy molecule due to its activity on multiple transcription factors, and the elucidation of the correlation between the concentration of delivered miRNA-15a and the down-/up-regulation of the BCL-2 level, documented for the first time in this work, could be an important contribution to guide its clinical application.


Assuntos
Transporte Biológico , Técnicas de Transferência de Genes , MicroRNAs/farmacologia , Plasmídeos/farmacologia , Endocitose/efeitos dos fármacos , Endocitose/genética , Grafite/química , Humanos , Lisossomos/química , Lisossomos/genética , MicroRNAs/química , MicroRNAs/genética , Plasmídeos/química , Plasmídeos/genética , Transfecção , beta-Ciclodextrinas/química , beta-Ciclodextrinas/farmacologia
17.
Nanotechnology ; 30(40): 405701, 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31247611

RESUMO

In this work, we present a thorough study on the evaluation of the photothermal conversion efficiencies of gold nanobipyramids (AuBPs) under irradiation by two phototherapeutic laser lines at 785 and 808 nm. Due to fine tunability of the longitudinal localized surface plasmon resonance (LSPR) of AuBPs along the entire biological window, AuBPs have great potential to be applied as efficient photothermal agents in specific hyperthermia applications. Aiming to identify the most suitable AuBPs for each laser line, here we synthetized AuBPs of six different aspect ratios with longitudinal LSPR ranging from 662 to 929 nm and compared their intrinsic photothermal properties in colloidal solutions under laser irradiation at various experimental parameters such as sample volume, optical density and laser power. In addition, the experimental plasmonic resonances of the as-prepared AuBPs were perfectly simulated and their theoretical extinction and absorption cross-sections provided by finite-difference time-domain technique. Finally, we found photothermal conversion efficiencies ranging from 40% to 97% for all AuBPs systems under both NIR irradiation laser lines concluding that for the 785 nm excitation wavelength the AuBPs with longitudinal LSPR at 802 nm are most efficient, whereas in the case of the 808 nm laser line the AuBPs with optical response at 812 nm exhibit the best thermal performance. These studies are crucial for designing AuBPs as effective phototherapy agents acting alone or in combination with other plasmon-based or plasmon-assisted therapies.

18.
ACS Appl Mater Interfaces ; 11(8): 7812-7822, 2019 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-30707545

RESUMO

There is still a lack of available techniques to follow noninvasively the intracellular processes as well to track or disentangle various signals from the therapeutic agents at the site of action in the target cells. We present here the assessment of the intracellular kinetics of doxorubicin (DOX) and gold nanoparticle (AuNP) carriers by mapping simultaneously fluorescence and photoluminescence signals by fluorescence lifetime imaging microscopy under two-photon excitation (TPE-FLIM). The new nano-chemotherapeutic system AuNPs@gelatin-hyd-DOX has been fabricated by DOX loading onto the surface of gelatin-biosynthesized AuNPs (AuNPs@gelatin) through a pH-sensitive hydrazone bond. The successful loading of DOX onto the AuNPs was studied by spectroscopic methods and steady-state fluorescence, and the nanosystem pH-responsive character was validated under simulated biological conditions at different pH values (i.e., pH 4.6, 5.3, and 7.4). Considering that the fluorescence lifetime of DOX molecules at a specific point in the cell is a reliable indicator of the discrimination of the different states of the drug in the internalization path, i.e., released versus loaded, the kinetics of AuNPs@gelatin-hyd-DOX cellular uptake and DOX release was compared to that of free DOX, resulting in two different drug internalization pathways. Finally, cell viability tests were conducted against NIH:OVCAR-3 cell line to prove the efficiency of our chemotherapeutic nanosystem. TPE-FLIM technique could be considered promising for noninvasive, high-resolution imaging of cells with improved capabilities over current one-photon-excited FLIM.


Assuntos
Doxorrubicina/metabolismo , Portadores de Fármacos/química , Ouro/química , Nanopartículas Metálicas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Gelatina/química , Humanos , Hidrazonas/química , Concentração de Íons de Hidrogênio , Cinética , Microscopia de Fluorescência por Excitação Multifotônica
19.
Front Chem ; 7: 55, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800650

RESUMO

In this work, we design new plasmonic paper-based nanoplatforms with interesting capabilities in terms of sensitivity, efficiency, and reproducibility for promoting multimodal biodetection via Localized Surface Plasmon Resonance (LSPR), Surface Enhanced Raman Spectroscopy (SERS), and Metal Enhanced Fluorescence (MEF). To succeed, we exploit the unique optical properties of gold nanobipyramids (AuBPs) deposited onto the cellulose fibers via plasmonic calligraphy using a commercial pen. The first step of the biosensing protocol was to precisely graft the previously chemically-formed p-aminothiophenol@Biotin system, as active recognition element for target streptavidin detection, onto the plasmonic nanoplatform. The specific capture of the target protein was successfully demonstrated using three complementary sensing techniques. As a result, while the LSPR based sensing capabilities of the nanoplatform were proved by successive 13-18 nm red shifts of the longitudinal LSPR associated with the change of the surface RI after each step. By employing the ultrasensitive SERS technique, we were able to indirectly confirm the molecular identification of the biotin-streptavidin interaction due to the protein fingerprint bands assigned to amide I, amide III, and Trp vibrations. Additionally, the formed biotin-streptavidin complex acted as a spacer to ensure an optimal distance between the AuBP surface and the Alexa 680 fluorophore for achieving a 2-fold fluorescence emission enhancement of streptavidin@Alexa 680 on the biotinylated nanoplatform compared to the same complex on bare paper (near the plasmonic lines), implementing thus a novel MEF sensing nanoplatform. Finally, by integrating multiple LSPR, SERS, and MEF nanosensors with multiplex capability into a single flexible and portable plasmonic nanoplatform, we could overcome important limits in the field of portable point-of-care diagnostics.

20.
Nutrients ; 12(1)2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31892138

RESUMO

Sea buckthorn oil, derived from the fruits of the shrub, also termed seaberry or sandthorn, is without doubt a strikingly rich source of carotenoids, in particular zeaxanthin and ß-carotene. In the present study, sea buckthorn oil and an oil-in-water emulsion were subjected to a simulated gastro-intestinal in vitro digestion, with the main focus on xanthophyll bioaccessibility. Zeaxanthin mono- and di-esters were the predominant carotenoids in sea buckthorn oil, with zeaxanthin dipalmitate as the major compound (38.0%). A typical fatty acid profile was found, with palmitic (49.4%), palmitoleic (28.0%), and oleic (11.7%) acids as the dominant fatty acids. Taking into account the high amount of carotenoid esters present in sea buckthorn oil, the use of cholesterol esterase was included in the in vitro digestion protocol. Total carotenoid bioaccessibility was higher for the oil-in-water emulsion (22.5%) compared to sea buckthorn oil (18.0%) and even higher upon the addition of cholesterol esterase (28.0% and 21.2%, respectively). In the case of sea buckthorn oil, of all the free carotenoids, zeaxanthin had the highest bioaccessibility (61.5%), followed by lutein (48.9%), making sea buckthorn oil a potential attractive source of bioaccessible xanthophylls.


Assuntos
Hippophae/química , Óleos Vegetais/química , Xantofilas/farmacocinética , Disponibilidade Biológica , Digestão , Emulsões/química , Ácidos Graxos/análise , Frutas/química , Suco Gástrico/enzimologia , Humanos , Intestino Delgado/enzimologia , Luteína/farmacocinética , Esterol Esterase/metabolismo , Xantofilas/análise , Zeaxantinas/farmacocinética , beta Caroteno/farmacocinética
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