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1.
Heliyon ; 9(9): e19470, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37810117

RESUMO

Whether a nuclear installation has radiological impact and, in that case, its extension, are the questions behind any environmental analysis of the installation along its operational life. This analysis is based on the detailed establishment of the radiological background of the area. Accordingly, the dismantling and decommissioning process (D&D) of a nuclear power plant starts with a radiological monitoring plan, which includes the radiological characterization of the area and of its surroundings. At the completion of the D&D, unrestricted use for the site will be permitted strictly in accordance with results of the radiological survey within the limits established by the local authorities. Groundwater quality is typically included in any radiological analysis since, among other reasons, a significant part of it is highly likely to end up being extracted for domestic use and hence, human consumption. While there is no regulation containing maximum activity concentration or radionuclide guidance values for water that may be destined for uses other than public consumption, if groundwater is considered a "part" of the land, dose criteria for site release can be applied. Therefore, together with the guidance levels to be established for the different radionuclides expected in the groundwater, the detection limits to be employed when performing routine radio analytical characterization procedures in the laboratory should also be provided. In this paper, we first propose a relation of the potential radionuclides to be analyzed in groundwater, together with their detection limits to be achieved when the determinations are performed in a laboratory, and subsequently, we discuss the most suitable analytical methodologies and resources that would be necessary to undertake radiological characterization plans from a practical point of view.

2.
European J Org Chem ; : e202201301, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36721524

RESUMO

Cyclopropanation reactions between C60 and different malonates decorated with monosaccharides and steroids using the Bingel-Hirsch methodology have allowed the obtention of a new family of hybrid compounds in good yields. A complete set of instrumental techniques has allowed us to fully characterize the hybrid derivatives and to determine the chemical structure of monocycloadducts. Besides, the proposed structures were investigated by cyclic voltammetry, which evidenced the exclusive reductive pattern of fullerene Bingel-type monoadducts. Theoretical calculations at the DFT-D3(BJ)/PBE 6-311G(d,p) level of the synthesized conjugates predict the most stable conformation and determine the factors that control the hybrid molecules' geometry. Some parameters such as polarity, lipophilicity, polar surface area, hydrophilicity index, and solvent-accessible surface area were also estimated, predicting its potential permeability and capability as cell membrane penetrators. Additionally, a molecular docking simulation has been carried out using the main protease of SARS-CoV-2 (Mpro) as the receptor, thus paving the way to study the potential application of these hybrids in biomedicine.

3.
J Mater Chem B ; 11(3): 675-686, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36562480

RESUMO

Safety assessment of carbon nanomaterials is of paramount importance since they are on the frontline for applications in sensing, bioimaging and drug delivery. The biocompatibility and safety of functionalized nanodiamonds (NDs) are here addressed through the study of the pro-inflammatory response of RAW-264.7 macrophages exposed to new nanodiamonds@corrole hybrids. The corrole unit selected is as a prototype for a hydrophobic organic molecule that can function as a NIR fluorophore reporter, an optical sensor, a photodynamic therapy agent or a photocatalyst. The new functional nanohybrids containing detonated nanodiamonds (NDs) were obtained through esterification using carboxylated NDs and glycol corroles. The success of the covalent functionalization via carbodiimide activation was confirmed through X-ray photoelectron spectroscopy (XPS), Raman and Fourier transform infrared (FTIR) spectroscopy. The UV-vis absorption and emission spectra of the hybrids are additive with respect to the corrole features. The cellular uptake, localization, cell viability and effects on immune cell activation of the new hybrids and of the precursors were carefully investigated using RAW-264.7 macrophages. Overall results showed that the ND@corrole hybrids had no pro-inflammatory effects on the RAW-264.7 macrophage cell line, making them an ideal candidate for a wide range of biomedical applications.


Assuntos
Nanodiamantes , Porfirinas , Nanodiamantes/química , Sistemas de Liberação de Medicamentos , Porfirinas/farmacologia , Macrófagos
4.
Angew Chem Int Ed Engl ; 61(43): e202211365, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36044587

RESUMO

The construction of supramolecular assemblies of heterogeneous materials at the nanoscale is an open challenge in science. Herein, new chiral graphene quantum dots (GQDs) prepared by amidation reaction introducing chiral amide groups and pyrene moieties into the periphery of GQDs are described. The analytical and spectroscopic data show an efficient chemical functionalization and the morphological study of the supramolecular ensembles using SEM and AFM microscopies reveals the presence of highly ordered fibers of several micrometers length. Fluorescence studies, using emission spectroscopy and confocal microscopy, reveal that the fibers stem from the π-π stacking of both pyrenes and GQDs, together with the hydrogen bonding interactions of the amide groups. Circular dichroism analysis supports the chiral nature of the supramolecular aggregates.

5.
Chem Sci ; 13(30): 8813-8820, 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35975161

RESUMO

The development of biosensors capable of achieving accurate and precise molecular measurements in the living body in pH-variable biological environments (e.g. subcellular organelles, biological fluids and organs) plays a significant role in personalized medicine. Because they recapitulate the conformation-linked signaling mechanisms, electrochemical aptamer-based (E-AB) sensors are good candidates to fill this role. However, this class of sensors suffers from a lack of a stable and pH-independent redox reporter to support their utility under pH-variable conditions. Here, in response, we demonstrate the efficiency of an electron donor π-extended tetrathiafulvalene (exTTF) as an excellent candidate (due to its good electrochemical stability and no proton participation in its redox reaction) of pH-independent redox reporters. Its use has allowed improvement of E-AB sensing performance in biological fluids under different pH conditions, achieving high-frequency, real-time molecular measurements in biological samples both in vitro and in the bladders of living rats.

6.
Nat Microbiol ; 7(6): 810-819, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35618773

RESUMO

Animals and microorganisms often establish close ecological relationships. However, much of our knowledge about animal microbiomes comes from two deeply studied groups: vertebrates and arthropods. To understand interactions on a broader scale of diversity, we characterized the bacterial microbiomes of close to 1,000 microscopic marine invertebrates from 21 phyla, spanning most of the remaining tree of metazoans. Samples were collected from five temperate and tropical locations covering three marine habitats (sediment, water column and intertidal macroalgae) and bacterial microbiomes were characterized using 16S ribosomal RNA gene sequencing. Our data show that, despite their size, these animals harbour bacterial communities that differ from those in the surrounding environment. Distantly related but coexisting invertebrates tend to share many of the same bacteria, suggesting that guilds of microorganisms preferentially associated with animals, but not tied to any specific host lineage, are the main drivers of the ecological relationship. Host identity is a minor factor shaping these microbiomes, which do not show the same correlation with host phylogeny, or 'phylosymbiosis', observed in many large animals. Hence, the current debate on the varying strength of phylosymbiosis within selected lineages should be reframed to account for the possibility that such a pattern might be the exception rather than the rule.


Assuntos
Microbiota , Animais , Bactérias/genética , Microbiota/genética , Filogenia , Vertebrados
7.
Hipertens. riesgo vasc ; 39(2): 69-78, abr.-jun. 2022. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-203956

RESUMO

Presentamos la adaptación española de las Guías Europeas de Prevención Cardiovascular 2021. En esta actualización además del abordaje individual, se pone mucho más énfasis en las políticas sanitarias como estrategia de prevención poblacional. Se recomienda el cálculo del riesgo vascular de manera sistemática a todas las personas adultas con algún factor de riesgo vascular. Los objetivos terapéuticos para el colesterol low density lipoprotein (LDL), la presión arterial y la glucemia no han cambiado respecto a las anteriores guías, pero se recomienda alcanzar estos objetivos de forma escalonada (etapas 1 y 2). Se recomienda llegar siempre hasta la etapa 2, y la intensificación del tratamiento dependerá del riesgo a los 10 años y de por vida, del beneficio del tratamiento, de las comorbilidades, de la fragilidad y de las preferencias de los pacientes. Las guías presentan por primera vez un nuevo modelo para calcular el riesgo Systematic Coronary Risk Evaluation-2 (SCORE2) y Systematic Coronary Risk Evaluation-2 Old person (SCORE2-OP) de morbimortalidad vascular en los próximos 10 años (infarto de miocardio, ictus y mortalidad vascular) en hombres y mujeres entre 40 y 89 años. Otra de las novedades sustanciales es el establecimiento de diferentes umbrales de riesgo dependiendo de la edad (< 50, 50-69 ≥ 70 años).Se presentan diferentes algoritmos de cálculo del riesgo vascular y tratamiento de los factores de riesgo vascular para personas aparentemente sanas, pacientes con diabetes y pacientes con enfermedad vascular aterosclerótica. Los pacientes con enfermedad renal crónica se considerarán de riesgo alto o muy alto según la tasa del filtrado glomerular y el cociente albúmina/creatinina. Se incluyen innovaciones en las recomendaciones sobre los estilos de vida, adaptadas a las recomendaciones del Ministerio de Sanidad, así como aspectos novedosos relacionados con el control de los lípidos, la presión arterial, la diabetes y la insuficiencia renal crónica.


Statement of the Spanish Interdisciplinary Vascular Prevention Committee on the updated European Guidelines on Cardiovascular Disease Prevention. We present the Spanish adaptation of the 2021 European Guidelines on Cardiovascular Disease (CVD) prevention in clinical practice. The current guidelines besides the individual approach greatly emphasize on the importance of population level approaches to the prevention of cardiovascular diseases. Systematic global CVD risk assessment is recommended in individuals with any major vascular risk factor. Regarding LDL-Cholesterol, blood pressure, and glycemic control in patients with diabetes mellitus, goals and targets remain as recommended in previous guidelines. However, it is proposed a new, stepwise approach (Step 1 and 2) to treatment intensification as a tool to help physicians and patients pursue these targets in a way that fits patient profile. After Step 1, considering proceeding to the intensified goals of Step 2 is mandatory, and this intensification will be based on 10-year CVD risk, lifetime CVD risk and treatment benefit, comorbidities and patient preferences. The updated SCORE algorithm—SCORE2, SCORE-OP— is recommended in these guidelines, which estimates an individual's 10-year risk of fatal and non-fatal CVD events (myocardial infarction, stroke) in healthy men and women aged 40-89 years. Another new and important recommendation is the use of different categories of risk according different age groups (< 50, 50-69 ≥ 70 years). Different flow charts of CVD risk and risk factor treatment in apparently healthy persons, in patients with established atherosclerotic CVD, and in diabetic patients are recommended. Patients with chronic kidney disease are considered high risk or very high-risk patients according to the levels of glomerular filtration rate and albumin-to-creatinine ratio. [...]


Assuntos
Humanos , Masculino , Feminino , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Diabetes Mellitus , Pressão Arterial , Estilo de Vida , Fatores de Risco , Guias de Prática Clínica como Assunto , Dieta Saudável , Hipertensão
8.
Hipertens Riesgo Vasc ; 39(2): 69-78, 2022.
Artigo em Espanhol | MEDLINE | ID: mdl-35331672

RESUMO

Statement of the Spanish Interdisciplinary Vascular Prevention Committee on the updated European Guidelines on Cardiovascular Disease Prevention. We present the Spanish adaptation of the 2021 European Guidelines on Cardiovascular Disease (CVD) prevention in clinical practice. The current guidelines besides the individual approach greatly emphasize on the importance of population level approaches to the prevention of cardiovascular diseases. Systematic global CVD risk assessment is recommended in individuals with any major vascular risk factor. Regarding LDL-Cholesterol, blood pressure, and glycemic control in patients with diabetes mellitus, goals and targets remain as recommended in previous guidelines. However, it is proposed a new, stepwise approach (Step 1 and 2) to treatment intensification as a tool to help physicians and patients pursue these targets in a way that fits patient profile. After Step 1, considering proceeding to the intensified goals of Step 2 is mandatory, and this intensification will be based on 10-year CVD risk, lifetime CVD risk and treatment benefit, comorbidities and patient preferences. The updated SCORE algorithm-SCORE2, SCORE-OP- is recommended in these guidelines, which estimates an individual's 10-year risk of fatal and non-fatal CVD events (myocardial infarction, stroke) in healthy men and women aged 40-89 years. Another new and important recommendation is the use of different categories of risk according different age groups (< 50, 50-69 ≥ 70 years). Different flow charts of CVD risk and risk factor treatment in apparently healthy persons, in patients with established atherosclerotic CVD, and in diabetic patients are recommended. Patients with chronic kidney disease are considered high risk or very high-risk patients according to the levels of glomerular filtration rate and albumin-to-creatinine ratio. New lifestyle recommendations adapted to the ones published by the Spanish Ministry of Health as well as recommendations focused on the management of lipids, blood pressure, diabetes and chronic renal failure are included.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Feminino , Humanos , Estilo de Vida , Masculino , Fatores de Risco
10.
Appl Radiat Isot ; 176: 109906, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34425351

RESUMO

Determination of 241Pu is an essential issue for radiation protection, as it is the precursor of some nuclides with high radiotoxicity. 241Pu is a low energy beta emitter, which makes its measurement more challenging than that of Pu alpha emitters. The most widely used method for the measurement of 241Pu is liquid scintillation counting (LSC). In this method, the assessment of Pu radiochemical yield is done by measuring the sample by alpha spectrometry before being lixiviated and measured by LSC. This double measurement affects uncertainty analysis, as well as decision threshold and detection limit, considering that both components of the total yield (radiochemical and lixiviation) should be contemplated. In this paper, and for quality assurance (QA) purposes, in-depth uncertainty and detection limit formulae for the proposed method, controlling correlations and considering all the parameters involved including chemical and lixiviation yields, have been developed. A sensitivity analysis of the uncertainty budget together with an assessment of 242Pu tracer quantity to be used, ensuring a total yield of at least 50% and a relative uncertainty of the leaching yield of at most 5%, have been carried out. In addition, an analysis of the impact of the real lixiviation yield value and its uncertainty on the results has been done. As a general conclusion, and considering the values of the parameters chosen for this work (samples of 1 g measured for 24 h by LSC), the 241Pu uncertainties range from 5% to 30% depending on the activity concentration values and the detection limits range from 14 to 30 Bq kg-1, depending on yield values. The main components of the uncertainty budget are the net 241Pu and background counts obtained in the LSC measurement for low contaminated samples while this is the case for the alpha gross count rate in LSC measurement of the alpha calibration source for highly contaminated samples. In addition, an analysis of possible interference by Pu alpha emitters in the 241Pu signal and a comparison of quench standard curves of 3H and 241Pu are also performed.

11.
Appl Radiat Isot ; 176: 109881, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34343747

RESUMO

The investigation of radioactivity in samples is an application of gamma-ray spectrometry dealing with low and very low level gamma-ray activities of different isotopes. Gamma-ray spectrometry performed in the framework of radiological environmental monitoring may be done after selective sampling processes or after a chemical purification of a sample. Both cases imply that only some specific radionuclides should contribute to the obtained spectrum. Gamma-ray spectrometry performed with medium energy resolution detectors may allow the possible distinction of their photopeaks. Therefore, a cerium bromide (CeBr3) detector can be particularly attractive for routine tasks in radiological environmental monitoring as it has a high efficiency, medium energy resolution and it can work at room temperature. This study describes the conditions under which a CeBr3 detector can serve for some routine analysis in radiological analysis of samples collected in the environment or collected by air-samplers in environmental radiological monitoring programmes.


Assuntos
Radioisótopos de Césio/análise , Monitoramento Ambiental/métodos , Poluentes Radioativos/análise , Contagem de Cintilação/instrumentação , Calibragem , Limite de Detecção , Radioisótopos/análise , Reprodutibilidade dos Testes , Espectrometria gama/métodos
13.
J Am Chem Soc ; 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33211959

RESUMO

Carbon nanodots (CNDs) undergo electron transfer in different scenarios. Previous studies have mainly focused on the electron-accepting features of CNDs in covalently linked donor-acceptor nanoconjugates. In view of this, we decided to carry out in this study the formation of covalently linked nanoconjugates that feature electron-donating pressure synthesized carbon nanodots (pCNDs) and electron-accepting 11,11,12,12-tetracyano-9,10-anthra-p-quinodimethane (TCAQ): pCND-TCAQ. The stability of the one-electron reduced form of TCAQ renders it the acceptor of choice. Detailed structural and electrochemical investigations allowed the characterization of pCND-TCAQ. Furthermore, investigations regarding intramolecular interactions, by means of steady-state and pump-probe transient absorption spectroscopies, allowed detection and characterization of three excited state species, in general, and the pCND•+-TCAQ•- charge-separated state, in particular.

14.
Rev Clin Esp (Barc) ; 220(7): 444-449, 2020 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32493596

RESUMO

Over the course of 2018 and 2019, the Spanish Society of Internal Medicine carried out a project called "The Future Hospital." Based on cumulative knowledge on the Spanish National Health System, this project seeks to transfer the observations on the organization of healthcare in future hospitals made by the Royal College of Physicians in the United Kingdom to the context of the Spanish healthcare system. The project's participants included numerous scientific and medical societies, professional associations in the health sector, and patient associations. This aim of this article is to highlight, in 10 points, predictions that arose from this project that we consider to be the most relevant, reserving the last point for the challenges for the field of internal medicine that can be surmised from these proposals.

15.
J Org Chem ; 85(4): 2426-2437, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-31922748

RESUMO

The reaction of C60 with pregnen-20-carboxaldehyde, a biologically active synthetic steroid, by using a 1,3-dipolar cycloaddition reaction (Prato's protocol) results in the formation of pyrrolidine rings bearing a new stereogenic center on the C2 of the five-membered ring. The formation of the fullerene-steroid hybrids proceeds with preference for the Re face of the 1,3-dipole, with formation of a diastereomeric mixture in 73:15 ratio. The investigation of the chiroptical properties of these conjugates allowed determining the absolute configuration of the new fulleropyrrolidines. In addition, a thorough spectroscopical study permitted to determine the structure of the two mono-cycloadducts. The electrochemical properties of the new hybrids were also evaluated by cyclic voltammetry, both systems exhibit three quasi-reversible reduction waves which are cathodically shifted in regard to the parent C60. Theoretical calculations help supporting the experimental data. A conformational study combining semiempirical methods and density functional theory has predicted the most stable diastereomer. On the basis of this agreement, a possible reaction mechanism is presented. Additionally, a molecular docking simulation has been carried out using the HIV-1 protease as receptor, thus paving the way to study the possible application of these stereoisomers in biomedicine.

16.
J Am Chem Soc ; 142(4): 1895-1903, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31876150

RESUMO

A series of molecular precursors, containing one (1 and 3) or three (2 and 4) pyrene anchors, covalently linked to porphyrins (free base or Zn), were prepared and characterized. All of them enable their π-π stacking onto low-dimensional nanocarbons including single-walled carbon nanotubes (SWCNTs) and nanographene (NG), their individualization, and their characterization. Microscopic (TEM, AFM) and spectroscopic (steady-state UV-vis and fluorescence, spectroelectrochemistry, and transient absorption measurements) techniques were at the forefront of the characterizations and were complemented by Raman spectroscopy and theoretical calculations. Of great importance is the Raman analysis, which corroborated n-doping of the nanocarbons due to the interactions with 1-4 when probed in the solid state. In solution, the situation is, however, quite different. Efficient charge separation was only observed for the graphene-based system NG/3.

17.
Chem Commun (Camb) ; 55(22): 3223-3226, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30806381

RESUMO

Water-soluble fluorescent graphene quantum dots have been successfully prepared through a top-down approach, that is, starting with graphite, and covalently functionalizing it with π-extended tetrathiafulvalene. Charge transfer investigations reveal noticeably slower charge recombination when compared with exTTF nanoconjugates featuring carbon nanodots, for which a larger presence of trap states is observed.

18.
Eur J Radiol ; 108: 201-207, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30396656

RESUMO

PURPOSE: To evaluate the diagnostic value of dedicated breast PET (dbPET) parallel imaging in mammographically or sonographically detected BI-RADS 4 (Breast Imaging Reporting And Data Systems) lesions. MATERIALS AND METHODS: After institutional review board and patient approvals, 50 consecutive women with 60 BI-RADS 4 breast lesions were prospectively included in the study. All patients underwent Magnetic Resonance Imaging (MRI) and dbPET before biopsy and fusion of both MRI and dbPET images was performed to better locate corresponding lesions. Final findings were compared with histological results. Sensitivity and specificity for dbPET were determined along with their respective 95%-confidence intervals. RESULTS: Histopathology examination revealed 18 malignant lesions (7 in situ and 11 invasive carcinomas) and 42 benign entities. The dedicated breast PET reported no evidence of malignancy in 41 patients, 9 of them with histological diagnosis of neoplasm. Besides, dbPET showed increased metabolically activity in 10 benign lesions and in 9 breast cancers. Two invasive carcinomas were located less than 1 cm from the pectoral muscle, which can explain that they were missed by dbPET because they were outside the field of view (FOV). There were other 6 false negative results, which corresponded to a 0.1 cm invasive lobular carcinoma and 5 in situ carcinomas. Sensitivity and specificity of dbPET were 50% and 76%, respectively. CONCLUSIONS: Our analysis does not allow the recommendation of dbPET for diagnosis of malignancy in BI-RADS 4 mammographic or US abnormalities, mainly due to its high false-negative rate for the detection of in situ carcinomas (85.7%). However, considering the lesions greater than 0.1 cm and included in the FOV, dbPET depicted all invasive carcinomas.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Adulto , Idoso , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Sistemas de Informação em Radiologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Adulto Jovem
19.
Chempluschem ; 83(4): 300-307, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31957276

RESUMO

Donor-acceptor-substituted alkynes, endowed with 11,11,12,12-tetracyano-9,10-anthraquinodimethane (TCAQ) and N,N-dimethylaniline (DMA) units, have been further functionalized by a [2+2] cycloaddition with tetracyanoethylene (TCNE) followed by a subsequent retro-electrocyclization to form distorted nonplanar structures with bridging 1,1,4,4-tetracyanobuta-1,3-diene (TCBD) units. Comprehensive spectroscopic, electrochemical, and computational studies have been carried out to compare the electronic communication in planar (alkyne bridges) and nonplanar (TCBD bridges) TCAQ-based push-pull chromophores. Cyclic voltammetry and UV/Vis absorption measurements confirm the electronic communication between the TCAQ and DMA units despite the nonplanarity of the TCBD group. The experimental trends are strongly supported by density functional theory calculations, which further support the active electron-withdrawing role of the TCBD bridges. The novel push-pull TCAQ-based derivatives incorporating the TCBD bridge show a broad absorption in the whole visible range while the structures are highly distorted from planarity.

20.
Angew Chem Int Ed Engl ; 57(4): 1001-1005, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29193715

RESUMO

Carbon nanodots (CNDs) were synthesized using low-cost and biocompatible starting materials such as citric acid/urea, under microwave irradiation, and constant pressure conditions. The obtained pressure-synthesized CNDs (pCNDs) were covalently modified with photo- and electroactive π-extended tetrathiafulvalene (exTTF) by means of a two-step esterification reaction, affording pCND-exTTF. The electronic interactions between the pCNDs and exTTF were investigated in the ground and excited states. Ultrafast pump-probe experiments assisted in corroborating that charge separation governs the deactivation of photoexcited pCND-exTTF. These size-regular structures, as revealed by AFM, are stable electron donor-acceptor conjugates of interest for a better understanding of basic processes such as artificial photosynthesis, catalysis, and photovoltaics, involving readily available fluorescent nanodots.

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