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1.
Anal Chim Acta ; 1316: 342878, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-38969399

RESUMO

Fluorescence analysis has been regarded as one of the commonly used analytical methods because of its advantages of simple operation, fast response, low cost and high sensitivity. So far, various fluorescent probes, with noble metal nanoclusters, quantum dots, organic dyes and metal organic frameworks as representatives, have been widely reported. However, single fluorescent probe often suffers from some deficiencies, such as low quantum yield, poor chemical stability, low water solubility and toxicity. To overcome these disadvantages, the introduction of cyclodextrins into fluorescent probes has become a fascinating approach. This review (with 218 references) systematically covers the research progress of fluorescent composites based on cyclodextrins in recent years. Preparation strategies, fluorescence properties, response mechanisms and applications in sensing (ions, organic pollutants, bio-related molecules, temperature, pH) and bioimaging of fluorescent composites based on cyclodextrins are summarized in detail. Finally, the current challenges and future perspectives of these composites in relative research fields are discussed.


Assuntos
Ciclodextrinas , Corantes Fluorescentes , Ciclodextrinas/química , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Humanos , Imagem Óptica , Fluorescência , Animais
2.
J Environ Sci (China) ; 146: 103-117, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38969439

RESUMO

The reliable application of field deployable fluorescent dissolved organic matter (fDOM) probes is hindered by several influencing factors which need to be compensated. This manuscript describes the corrections of temperature, pH, turbidity and inner filter effect on fluorescence signal of a commercial fDOM probe (fDOMs). For this, Australian waters with wide ranging qualities were selected, e.g. dissolved organic carbon (DOC) ranging from ∼1 to ∼30 mg/L, specific UV absorbance at 254 nm from ∼1 to ∼6 L/m/mg and turbidity from ∼1 to ∼ 350 FNU. Laboratory-based model calibration experiments (MCEs) were performed. A model template was developed and used for the development of the correction models. For each factor, data generated through MCEs were used to determine model coefficient (α) values by fitting the generated model to the experimental data. Four discrete factor models were generated by determination of a factor-specific α value. The α values derived for each water of the MCEs subset were consistent for each factor model. This indicated generic nature of the four α values across wide-ranging water qualities. High correlation between fDOMs and DOC were achieved after applying the four-factor compensation models to new data (r, 0.96, p < 0.05). Also, average biases (and %) between DOC predicted through fDOMs and actual DOC were decreased by applying the four-factor compensation model (from 3.54 (60.9%) to 1.28 (16.7%) mg/L DOC). These correction models were incorporated into a Microsoft EXCEL-based software termed EXOf-Correct for ready-to-use applications.


Assuntos
Monitoramento Ambiental , Água Doce , Monitoramento Ambiental/métodos , Fluorescência , Modelos Químicos , Corantes Fluorescentes/química , Modelos Teóricos , Poluentes Químicos da Água/análise
3.
Commun Biol ; 7(1): 799, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956304

RESUMO

In this paper, we propose a fluorescence-lifetime imaging microscopy (FLIM) multiplexing system based on the fluorogen-activating protein FAST. This genetically encoded fluorescent labeling platform employs FAST mutants that activate the same fluorogen but provide different fluorescence lifetimes for each specific protein-dye pair. All the proposed probes with varying lifetimes possess nearly identical and the smallest-in-class size, along with quite similar steady-state optical properties. In live mammalian cells, we target these chemogenetic tags to two intracellular structures simultaneously, where their fluorescence signals are clearly distinguished by FLIM. Due to the unique structure of certain fluorogens under study, their complexes with FAST mutants display a monophasic fluorescence decay, which may facilitate enhanced multiplexing efficiency by reducing signal cross-talks and providing optimal prerequisites for signal separation upon co-localized and/or spatially overlapped labeling.


Assuntos
Corantes Fluorescentes , Microscopia de Fluorescência , Microscopia de Fluorescência/métodos , Corantes Fluorescentes/química , Humanos , Animais , Fluorescência , Mutação
4.
Sci Rep ; 14(1): 15279, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961181

RESUMO

Advanced 3D high-resolution imaging techniques are essential for investigating biological challenges, such as neural circuit analysis and tumor microenvironment in intact tissues. However, the fluorescence signal emitted by endogenous fluorescent proteins in cleared or expanded biological samples gradually diminishes with repeated irradiation and prolonged imaging, compromising its ability to accurately depict the underlying scientific problem. We have developed a strategy to preserve fluorescence in cleared and expanded tissue samples during prolonged high-resolution three-dimensional imaging. We evaluated various compounds at different concentrations to determine their ability to enhance fluorescence intensity and resistance to photobleaching while maintaining the structural integrity of the tissue. Specifically, we investigated the impact of EDTP utilization on GFP, as it has been observed to significantly improve fluorescence intensity, resistance to photobleaching, and maintain fluorescence during extended room temperature storage. This breakthrough will facilitate extended hydrophilic and hydrogel-based clearing and expansion methods for achieving long-term high-resolution 3D imaging of cleared biological tissues by effectively safeguarding fluorescent proteins within the tissue.


Assuntos
Proteínas de Fluorescência Verde , Imageamento Tridimensional , Proteínas de Fluorescência Verde/metabolismo , Animais , Imageamento Tridimensional/métodos , Camundongos , Fotodegradação , Fluorescência
5.
Mikrochim Acta ; 191(7): 437, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951284

RESUMO

A stable DNA signal amplification sensor was developed on account of rolling circle amplification (RCA). This sensor includes target DNA-controlled rolling circle amplification technology and locking probe DNA replacement technology, which can be used to detect DNA fragments with genetic information, thus constructing a biosensor for universal detection of DNA. This study takes the homologous DNA of human immunodeficiency virus (HIV) and let-7a as examples to describe this biosensor. The padlock probe is first cyclized by T4 DNA ligase in response to the target's reaction with it. Then, rolling cycle amplification is initiated by Phi29 DNA polymerase, resulting in the formation of a lengthy chain with several triggers. These triggers can open the locked probe LP1 with the fluorescence signal turned off, so that it can continue to react with H2 to form a stable H1-H2 double strand. This regulates the distance between B-DNA modified by the quenching group and H1 modified by fluorescent group, and the fluorescence signal is recovered.


Assuntos
Técnicas Biossensoriais , Sondas de DNA , Técnicas de Amplificação de Ácido Nucleico , Técnicas Biossensoriais/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , Humanos , Sondas de DNA/química , Sondas de DNA/genética , Corantes Fluorescentes/química , DNA Viral/análise , DNA Viral/genética , DNA/química , DNA/genética , Espectrometria de Fluorescência/métodos , Fluorescência , DNA Polimerase Dirigida por DNA/metabolismo , DNA Polimerase Dirigida por DNA/química , Limite de Detecção , HIV/genética
7.
Luminescence ; 39(7): e4818, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39004769

RESUMO

Fexofenadine (FEX) is a non-sedating antihistamine commonly used for the treatment of allergic conditions such as seasonal rhinitis and chronic idiopathic urticaria. This study describes the tuning "ON" the intrinsic fluorescence of FEX by switching "OFF" its intramolecular photoinduced electron transfer (PET) through the protonation of the piperidinyl nitrogen atom using sulfuric acid. The resulting fluorescence was utilized as a basis for the development of a highly sensitive microwell spectrofluorimetric assay (MW-SFA) for the one-step determination of FEX in pharmaceutical tablets and plasma. The linear range of the assay was 10-500 ng ml-1, and its limit of quantitation was 25.9 ng ml-1. The proposed MW-SFA was successfully applied to analyze FEX in pharmaceutical tablets and plasma samples, demonstrating good accuracy and precision. The greenness of the assay was confirmed using three metric assessment tools. In conclusion, the MW-SFA is a straightforward, single-step analysis that requires no experimental adjustments. It offers high sensitivity, efficient sample processing, and environmental sustainability. This assay is highly recommended for pharmaceutical quality control and clinical lab use, particularly for measuring FEX levels.


Assuntos
Espectrometria de Fluorescência , Comprimidos , Terfenadina , Terfenadina/análogos & derivados , Terfenadina/sangue , Terfenadina/análise , Terfenadina/química , Transporte de Elétrons , Humanos , Fluorescência , Processos Fotoquímicos , Ensaios de Triagem em Larga Escala , Estrutura Molecular
8.
Anal Chem ; 96(28): 11603-11610, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38953495

RESUMO

Long noncoding RNAs (lncRNAs) act as the dynamic regulatory molecules that control the expression of genes and affect numerous biological processes, and their dysregulation is associated with tumor progression. Herein, we develop a fluorescent light-up aptasensor to simultaneously measure multiple lncRNAs in living cells and breast tissue samples based on the DNAzyme-mediated cleavage reaction and transcription-driven synthesis of light-up aptamers. When target lncRNAs are present, they can be recognized by template probes to form the active DNAzyme structures, initiating the T4 PNK-catalyzed dephosphorylation-triggered extension reaction to generate double-strand DNAs with the T7 promoter sequences. The corresponding T7 promoters can initiate the transcription amplification catalyzed by the T7 RNA polymerase to generate abundant Broccoli aptamers and malachite green aptamers, which can bind DFHBI-1T and MG to generate strong fluorescence signals. Taking advantage of the good selectivity of DNAzyme-mediated cleavage of lncRNAs, high amplification efficiency of T7 transcription-driven amplification reaction, and bright fluorescence of the RNA aptamer-fluorophore complex, this method exhibits high sensitivity with a detection limit of 21.4 aM for lncRNA HOTAIR and 18.47 aM for lncRNA MALAT1, and it can accurately measure multiple lncRNAs in both tumor cell lines and breast tissue samples, providing a powerful paradigm for biomedical research and early clinic diagnostics.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , DNA Catalítico , Corantes Fluorescentes , RNA Longo não Codificante , DNA Catalítico/química , DNA Catalítico/metabolismo , RNA Longo não Codificante/análise , RNA Longo não Codificante/metabolismo , RNA Longo não Codificante/genética , Humanos , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes/química , Limite de Detecção , Fluorescência
9.
Anal Chem ; 96(28): 11205-11215, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38967035

RESUMO

Lipid nanoparticles (LNPs) are emerging as one of the most promising drug delivery systems. The long-circulating effect of intact LNPs (i-LNPs) is the key to efficacy and toxicity in vivo. However, the significant challenge is specific and sensitive detection of i-LNPs. Herein, a dual-recognition fluorescence enzyme-linked immunosorbent assay (DR-FELISA) was developed to directly isolate and detect i-LNPs by combining dual-recognition separation with a one-step signal amplification strategy. The microplates captured and enriched i-LNPs through antibody-antigen reaction. Dual-chol probes were spontaneously introduced into the lipid bilayer of captured i-LNPs, converting the detection of i-LNPs into the detection of double-cholesterol probes. Finally, the end of the dual-chol probes initiated the localized scaffolding autocatalytic DNA circuits (SADC) system for further signal amplification. The SADC system provides a sensitive and efficient amplifier through localized network structures and self-assembled triggers. Simultaneous recognition of i-LNPs surface PEG-lipid and lipid bilayer structures significantly eliminates interference from biological samples. i-LNPs were detected with high selectivity, ranging from 0.2 to 1.25 mg/mL with a limit of detection of 0.1 mg/mL. Moreover, this method allows the isolation and quantitative analysis of different formulations of i-LNPs in serum samples with a satisfactory recovery rate ranging from 94.8 to 116.3%. Thus, the DR-FELISA method provides an advanced platform for the exclusive and sensitive detection of i-LNPs, providing new insights for the study of the quality and intracorporal process of complex formulations.


Assuntos
DNA , Ensaio de Imunoadsorção Enzimática , Nanopartículas , Nanopartículas/química , DNA/química , Limite de Detecção , Lipídeos/química , Fluorescência , Catálise , Lipossomos
11.
Sci Rep ; 14(1): 16233, 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004658

RESUMO

Saline-sodic stress restricts the absorption of zinc by rice, consequently impacting the photosynthesis process of rice plants. In this experiment, Landrace 9 was selected as the test material and the potting method was employed to investigate the influence of ZnO nanoparticles (ZnO NPs) on zinc absorption and chlorophyll fluorescence in rice grown in saline-sodic land. The research findings demonstrate that the application of ZnO NPs proves to be more advantageous for the growth of rice in saline-sodic soil. Notably, the application of ZnO NPs significantly decreases the levels of Na+ and MDA in rice leaves in saline-sodic soil, while increasing the levels of K+ and Zn2+. Additionally, ZnO NPs enhances the content of chloroplast pigments, specific energy flux, quantum yield, and the performance of active PSII reaction center (PIABS) in rice leaves under saline-sodic stress. Furthermore, the relative variable fluorescence (WK and VJ) and quantum energy dissipation rate (φDo) of rice are also reduced. Therefore, the addition of ZnO NPs enhances the transfer of electrons and energy within the rice photosystem when subjected to saline-sodic stress. This promotes photosynthesis in rice plants growing in saline-sodic land, increasing their resistance to saline-sodic stress and ultimately facilitating their growth and development.


Assuntos
Oryza , Fotossíntese , Folhas de Planta , Solo , Óxido de Zinco , Oryza/metabolismo , Oryza/efeitos dos fármacos , Oryza/crescimento & desenvolvimento , Óxido de Zinco/farmacologia , Fotossíntese/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/efeitos dos fármacos , Solo/química , Clorofila/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Nanopartículas Metálicas/química , Fluorescência , Salinidade
12.
Mikrochim Acta ; 191(8): 464, 2024 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007936

RESUMO

Rapid and high-sensitive Salmonella detection in milk is important for preventing foodborne disease eruption. To overcome the influence of the complex ingredients in milk on the sensitive detection of Salmonella, a dual-signal reporter red fluorescence nanosphere (RNs)-Pt was designed by combining RNs and Pt nanoparticles. After being equipped with antibodies, the immune RNs-Pt (IRNs-Pt) provide an ultra-strong fluorescence signal when excited by UV light. With the assistance of the H2O2/TMB system, a visible color change appeared that was attributed to the strong peroxidase-like catalytic activity derived from Pt nanoparticles. The IRNs-Pt in conjunction with immune magnetic beads can realize that Salmonella typhimurium (S. typhi) was captured, labeled, and separated effectively from untreated reduced-fat pure milk samples. Under the optimal experimental conditions, with the assay, as low as 50 CFU S. typhi can be converted to detectable fluorescence and absorbance signals within 2 h, suggesting the feasibility of practical application of the assay. Meanwhile, dual-signal modes of quantitative detection were realized. For fluorescence signal detection (emission at 615 nm), the linear correlation between signal intensity and the concentration of S. typhi was Y = 83C-3321 (R2 = 0.9941), ranging from 103 to 105 CFU/mL, while for colorimetric detection (absorbamce at 450 nm), the relationship between signal intensity and the concentration of S. typhi was Y = 2.9logC-10.2 (R2 = 0.9875), ranging from 5 × 103 to 105 CFU/mL. For suspect food contamination by foodborne pathogens, this dual-mode signal readout assay is promising for achieving the aim of convenient preliminary screening and accurate quantification simultaneously.


Assuntos
Colorimetria , Leite , Salmonella typhimurium , Leite/microbiologia , Leite/química , Salmonella typhimurium/isolamento & purificação , Colorimetria/métodos , Animais , Nanopartículas Metálicas/química , Limite de Detecção , Platina/química , Peróxido de Hidrogênio/química , Fluorescência , Nanosferas/química , Microbiologia de Alimentos/métodos , Contaminação de Alimentos/análise , Espectrometria de Fluorescência/métodos
13.
Bioconjug Chem ; 35(7): 971-980, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38958375

RESUMO

Conventional serum markers often fail to accurately detect cholestasis accompanying many liver diseases. Although elevation in serum bile acid (BA) levels sensitively reflects impaired hepatobiliary function, other factors altering BA pool size and enterohepatic circulation can affect these levels. To develop fluorescent probes for extracorporeal noninvasive hepatobiliary function assessment by real-time monitoring methods, 1,3-dipolar cycloaddition reactions were used to conjugate near-infrared (NIR) fluorochromes with azide-functionalized BA derivatives (BAD). The resulting compounds (NIRBADs) were chromatographically (FC and PTLC) purified (>95%) and characterized by fluorimetry, 1H NMR, and HRMS using ESI ionization coupled to quadrupole TOF mass analysis. Transport studies using CHO cells stably expressing the BA carrier NTCP were performed by flow cytometry. Extracorporeal fluorescence was detected in anesthetized rats by high-resolution imaging analysis. Three NIRBADs were synthesized by conjugating alkynocyanine 718 with cholic acid (CA) at the COOH group via an ester (NIRBAD-1) or amide (NIRBAD-3) spacer, or at the 3α-position by a triazole link (NIRBAD-2). NIRBADs were efficiently taken up by cells expressing NTCP, which was inhibited by taurocholic acid (TCA). Following i.v. administration of NIRBAD-3 to rats, liver uptake and consequent release of NIR fluorescence could be extracorporeally monitored. This transient organ-specific handling contrasted with the absence of release to the intestine of alkynocyanine 718 and the lack of hepatotropism observed with other probes, such as indocyanine green. NIRBAD-3 administration did not alter serum biomarkers of hepatic and renal toxicity. NIRBADs can serve as probes to evaluate hepatobiliary function by noninvasive extracorporeal methods.


Assuntos
Ácidos e Sais Biliares , Corantes Fluorescentes , Fígado , Animais , Ácidos e Sais Biliares/química , Corantes Fluorescentes/química , Ratos , Fígado/metabolismo , Fígado/diagnóstico por imagem , Células CHO , Cricetulus , Testes de Função Hepática/métodos , Masculino , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ratos Sprague-Dawley , Fluorescência
14.
Bioconjug Chem ; 35(7): 1024-1032, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38963403

RESUMO

Tetrazine-derived fluorogenic labels are extensively studied for their potential in biological and medical imaging. Nonetheless, the fluorescence quenching mechanism in numerous precursors continues to be debated, particularly as the wavelengths extend into the red and near-infrared (NIR) regions. This challenge poses obstacles to systematically optimizing their fluorogenicity, i.e., achieving red-shifted wavelengths and improved fluorescence turn-on signals through click reactions. This paper highlights the significance of photoinduced charge centralization (PCC), a quenching mechanism observed in tetrazine-fused fluorogenic labels with integrated π-conjugations. PCC is primarily responsible for the quenching effects observed in such labels emitting in the red-to-NIR spectrum. Drawing from structure-property relationships, this study proposes two molecular design strategies that incorporate the PCC mechanism and constitutional isomerization to develop high-performance tetrazine-based labels. These strategies facilitate multiplex fluorescence imaging following click reactions, promising significant advancements in bio-orthogonal imaging techniques.


Assuntos
Corantes Fluorescentes , Corantes Fluorescentes/química , Compostos Heterocíclicos com 1 Anel/química , Fluorescência , Química Click , Imagem Óptica/métodos , Processos Fotoquímicos
15.
Kyobu Geka ; 77(6): 464-469, 2024 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-39009542

RESUMO

A 46-year-old man was treated with ascites due to idiopathic portal hypertension. Chest X-ray showed a massive pleural effusion on the right side. Also, contrast-enhanced ultrasonography showed that contrast medium was effusing from abdominal cavity into the thoracic cavity via diaphragm. He was diagnosed with pleuroperitoneal communication. Thoracoscopic surgery was performed and thoracoscope revealed ascites with indocyanine green (ICG) drained from multiple cystic area in the central tendon of the diaphragm. After suturing with non-absorbable thread with reinforcement, the whole diaphragm was covered with a polyglycolic acid sheet and fibrin glue. Postoperatively, there was no reaccumulation of pleural effusion. ICG fluorescence intraoperative imaging was an useful method in detecting the pleural holes.


Assuntos
Verde de Indocianina , Humanos , Masculino , Pessoa de Meia-Idade , Fluorescência , Doenças Peritoneais/diagnóstico por imagem , Doenças Peritoneais/cirurgia , Toracoscopia
16.
J Photochem Photobiol B ; 257: 112965, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955078

RESUMO

This research aimed to develop natural plant systems to serve as biological sentinels for the detection of organophosphate pesticides in the environment. The working hypothesis was that the presence of the pesticide in the environment caused changes in the content of pigments and in the photosynthetic functioning of the plant, which could be evaluated non-destructively through the analysis of reflected light and emitted fluorescence. The objective of the research was to furnish in vivo indicators derived from spectroscopic parameters, serving as early alert signals for the presence of organophosphates in the environment. In this context, the effects of two pesticides, Chlorpyrifos and Dimethoate, on the spectroscopic properties of aquatic plants (Vallisneria nana and Spathyfillum wallisii) were studied. Chlorophyll-a variable fluorescence allowed monitoring both pesticides' presence before any damage was observed at the naked eye, with the analysis of the fast transient (OJIP curve) proving more responsive than Kautsky kinetics, steady-state fluorescence, or reflectance measurements. Pesticides produced a decrease in the maximum quantum yield of PSII photochemistry, in the proportion of PSII photochemical deexcitation relative to PSII non photochemical decay and in the probability that trapped excitons moved electrons into the photosynthetic transport chain beyond QA-. Additionally, an increase in the proportion of absorbed energy being dissipated as heat rather than being utilized in the photosynthetic process, was notorious. The pesticides induced a higher deactivation of chlorophyll excited states by photophysical pathways (including fluorescence) with a decrease in the quantum yields of photosystem II and heat dissipation by non-photochemical quenching. The investigated aquatic plants served as sentinels for the presence of pesticides in the environment, with the alert signal starting within the first milliseconds of electronic transport in the photosynthetic chain. Organophosphates damage animals' central nervous systems similarly to certain compounds found in chemical weapons, thus raising the possibility that sentinel plants could potentially signal the presence of such weapons.


Assuntos
Clorofila , Clorpirifos , Clorofila/metabolismo , Clorofila/química , Clorpirifos/metabolismo , Clorpirifos/toxicidade , Fluorescência , Praguicidas/toxicidade , Praguicidas/metabolismo , Fotossíntese/efeitos dos fármacos , Dimetoato/toxicidade , Dimetoato/metabolismo , Espectrometria de Fluorescência , Complexo de Proteína do Fotossistema II/metabolismo , Complexo de Proteína do Fotossistema II/química , Monitoramento Ambiental/métodos , Clorofila A/metabolismo , Clorofila A/química , Cinética , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/metabolismo
17.
ACS Appl Mater Interfaces ; 16(28): 35925-35935, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38950334

RESUMO

The development of efficient theranostic nanoagents for the precise diagnosis and targeted therapy of glioblastoma (GBM) remains a big challenge. Herein, we designed and developed porphyrin-based organic nanoparticles (PNP NPs) with strong emission in the near-infrared IIa window (NIR-IIa) for orthotopic GBM theranostics. PNP NPs possess favorable photoacoustic and photothermal properties, high photostability, and low toxicity. After modification with the RGD peptide, the obtained PNPD NPs exhibited enhanced blood-brain barrier (BBB) penetration capability and GBM targeting ability. NIR-IIa imaging was employed to monitor the in vivo biodistribution and accumulation of the nanoparticles, revealing a significant enhancement in penetration depth and signal-to-noise ratio. Both in vitro and in vivo results demonstrated that PNPD NPs effectively inhibited the proliferation of tumor cells and induced negligible side effects in normal brain tissues. In general, the work presented a kind of brain-targeted porphyrin-based NPs with NIR-IIa fluorescence for orthotopic glioblastoma theranostics, showing promising prospects for clinical translation.


Assuntos
Glioblastoma , Nanopartículas , Porfirinas , Nanomedicina Teranóstica , Glioblastoma/diagnóstico por imagem , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Glioblastoma/metabolismo , Animais , Nanopartículas/química , Humanos , Porfirinas/química , Porfirinas/farmacologia , Camundongos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Raios Infravermelhos , Distribuição Tecidual , Barreira Hematoencefálica/metabolismo , Camundongos Nus , Antineoplásicos/química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Fluorescência
18.
Astrobiology ; 24(7): 710-720, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023355

RESUMO

In a previous experiment, we demonstrated the capability of flow cytometry as a potential life detection technology for icy moons using exogenous fluorescent stains (Wallace et al., 2023). In this companion experiment, we demonstrated the capability of flow cytometry to detect life using intrinsically fluorescent biomolecules in addition to exogenous stains. We used a method similar to our previous work to positively identify six classes of intrinsically fluorescent biomolecules: flavins, carotenoids, chlorophyll, tryptophan, NAD+, and NAD(P)H. We demonstrated the effectiveness of this method with six known organisms and known abiotic material and showed that the cytometer is easily able to distinguish the known organisms and the known abiotic material by using the intrinsic fluorescence of these six biomolecules. To simulate a life detection experiment on an icy moon lander, we used six natural samples with unknown biotic and abiotic content. We showed that flow cytometry can identify all six intrinsically fluorescent biomolecules and can separate the biotic material from the known abiotic material on scatter plots. The use of intrinsically fluorescent biomolecules in addition to exogenous stains will potentially cast a wider net for life detection on icy moons using flow cytometry.


Assuntos
Citometria de Fluxo , Citometria de Fluxo/métodos , Corantes Fluorescentes/química , Fluorescência , Exobiologia/métodos , Triptofano/análise , Clorofila/análise , NAD/análise , Carotenoides/análise , NADP/análise
19.
Biol Pharm Bull ; 47(7): 1282-1287, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38987177

RESUMO

Assay systems for evaluating compound protein-binding affinities are essential for developing agonists and/or antagonists. Targeting individual members of a protein family can be extremely important and for this reason it is critical to have methods for evaluating selectivity. We have previously reported a fluorescence recovery assay that employs a fluorescein-labelled probe to determine IC50 values of ATP-competitive type 1 inhibitors of polo-like kinase 1 (Plk1). This probe is based on the potent Plk1 inhibitor BI2536 [fluorescein isothiocyanate (FITC)-polyethylene glycol (PEG)-lysine (Lys) (BI2536) 1]. Herein, we extend this approach to the highly homologous Plk2 and Plk3 members of this kinase family. Our results suggest that this assay system is suitable for evaluating binding affinities against Plk2 and Plk3 as well as Plk1. The new methodology represents the first example of evaluating N-terminal catalytic kinase domain (KD) affinities of Plk2 and Plk3. It represents a simple and cost-effective alternative to traditional kinase assays to explore the KD-binding compounds against Plk2 and Plk3 as well as Plk1.


Assuntos
Proteínas de Ciclo Celular , Quinase 1 Polo-Like , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/antagonistas & inibidores , Proteínas Proto-Oncogênicas/metabolismo , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/antagonistas & inibidores , Humanos , Ligação Proteica , Inibidores de Proteínas Quinases/farmacologia , Fluorescência , Quinases Polo-Like , Pteridinas , Proteínas Supressoras de Tumor
20.
Sci Rep ; 14(1): 15697, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38977739

RESUMO

The analysis of recombinant proteins in complex solutions is often accomplished with tag-specific antibodies in western blots. Recently, I introduced an antibody-free alternative wherein tagged proteins are visualized directly within polyacrylamide gels. For this, I used the protein ligase Connectase to selectively attach fluorophores to target proteins possessing an N-terminal recognition sequence. In this study, I extend this methodology to encompass the detection and quantification of C-terminally tagged proteins. Similar to the N-terminal labeling method, this adapted procedure offers increased speed, heightened sensitivity, and an improved signal-to-noise ratio when compared to western blots. It also eliminates the need for sample-specific optimization, enables more consistent and precise quantifications, and uses freely available reagents. This study broadens the applicability of in-gel fluorescence detection methods and thereby facilitates research on recombinant proteins.


Assuntos
Proteínas Recombinantes , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/química , Fluorescência , Corantes Fluorescentes/química , Eletroforese em Gel de Poliacrilamida/métodos , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Humanos
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