RESUMO
We report a polymer-based sensor that rapidly detects cancer based on changes in serum protein levels. Using three ratiometric fluorescence outputs, this simple system identifies early stage and metastatic lung cancer with a high level of accuracy exceeding many biomarker-based assays, making it an attractive strategy for point-of-care testing.
Assuntos
Biomarcadores Tumorais/sangue , Proteínas Sanguíneas/análise , Corantes Fluorescentes/química , Neoplasias Pulmonares/diagnóstico por imagem , Polímeros/química , Animais , Fluorescência , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Transgênicos , Estrutura Molecular , Neoplasias Experimentais/sangue , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/secundário , Testes ImediatosRESUMO
Effective correlation of the in vitro and in vivo stability of nanoparticle-based platforms is a key challenge in their translation into the clinic. Here, we describe a dual imaging method that site-specifically reports the stability of monolayer-functionalized nanoparticles in vivo. This approach uses laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) imaging to monitor the distributions of the nanoparticle core material and laser desorption/ionization mass spectrometry (LDI-MS) imaging to report on the monolayers on the nanoparticles. Quantitative comparison of the images reveals nanoparticle stability at the organ and suborgan level. The stability of particles observed in the spleen was location-dependent and qualitatively similar to in vitro studies. In contrast, in vivo stability of the nanoparticles in the liver differed dramatically from in vitro studies, demonstrating the importance of in vivo assessment of nanoparticle stability.
Assuntos
Ouro/farmacocinética , Nanopartículas Metálicas/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Animais , Ouro/administração & dosagem , Ouro/análise , Injeções , Fígado/metabolismo , Nanopartículas Metálicas/administração & dosagem , Camundongos , Camundongos Endogâmicos BALB C , Baço/metabolismoRESUMO
Surface chemistry plays a deciding role in nanoparticle biodistribution, yet very little is known about how surface chemistry influences the suborgan distributions of nanomaterials. Here, using quantitative imaging based on laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), we demonstrate that surface charge dictates the suborgan distributions of nanoparticles in the kidney, liver, and spleen of mice intravenously injected with functionalized gold nanoparticles. Images of the kidney show that positively charged nanoparticles accumulate extensively in the glomeruli, the initial stage in filtering for the nephron, suggesting that these nanoparticles may be filtered by the kidney at a different rate than the neutral or negatively charged nanoparticles. We find that positively and negatively charged nanoparticles accumulate extensively in the red pulp of the spleen. In contrast, uncharged nanoparticles accumulate in the white pulp and marginal zone of the spleen to a greater extent than the positively or negatively charged nanoparticles. Moreover, these uncharged nanoparticles are also more likely to be found associated with Kupffer cells in the liver. Positively charged nanoparticles accumulate extensively in liver hepatocytes, whereas negatively charged nanoparticles show a broader distribution in the liver. Together these observations suggest that neutral nanoparticles having 2 nm cores may interact with the immune system to a greater extent than charged nanoparticles, highlighting the value of determining the suborgan distributions of nanomaterials for delivery and imaging applications.
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Gold nanoparticles provide an excellent platform for biological and material applications due to their unique physical and chemical properties. However, decreased colloidal stability and formation of irreversible aggregates while freeze-drying nanomaterials limit their use in real world applications. Here, we report a new generation of surface ligands based on a combination of short oligo (ethylene glycol) chains and zwitterions capable of providing nonfouling characteristics while maintaining colloidal stability and functionalization capabilities. Additionally, conjugation of these gold nanoparticles with avidin can help the development of a universal toolkit for further functionalization of nanomaterials.
Assuntos
Ouro/química , Nanopartículas Metálicas/química , Etilenoglicol/química , Ligantes , Nanoestruturas/normasRESUMO
The surface properties of nanoparticles (NPs) dictate their interaction with the outside world. The use of precisely designed molecular ligands to control NP surface properties provides an important toolkit for modulating their interaction with biological systems, facilitating their use in biomedicine. In this review we will discuss the application of the atom-by-atom control provided by organic synthesis to the generation of engineered nanoparticles, with emphasis on how the functionalization of NPs with these "small" organic molecules (Mw < 1,000) can be used to engineer NPs for a wide range of applications.
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Using a family of cationic gold nanoparticles (NPs) with similar size and charge, we demonstrate that proper surface engineering can control the nature and identity of protein corona in physiological serum conditions. The protein coronas were highly dependent on the hydrophobicity and arrangement of chemical motifs on NP surface. The NPs were uptaken in macrophages in a corona-dependent manner, predominantly through recognition of specific complement proteins in the NP corona. Taken together, this study shows that surface functionality can be used to tune the protein corona formed on NP surface, dictating the interaction of NPs with macrophages.
Assuntos
Ouro/química , Macrófagos/metabolismo , Nanopartículas Metálicas/química , Coroa de Proteína/metabolismo , Animais , Cátions , Humanos , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Tamanho da Partícula , Ligação Proteica , Células RAW 264.7 , Propriedades de SuperfícieRESUMO
Functionalized gold nanoparticles (AuNPs) have unique properties that make them important biomedical materials. Optimal use of these materials, though, requires an understanding of their fate in vivo. Here we describe the use of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) to image the biodistributions of AuNPs in tissues from mice intravenously injected with AuNPs. We demonstrate for the first time that the distributions of very small (â¼2 nm core) monolayer-protected AuNPs can be imaged in animal tissues at concentrations in the low parts-per-billion range. Moreover, the LA-ICP-MS images reveal that the monolayer coatings on the injected AuNPs influence their distributions, suggesting that the AuNPs remain intact in vivo and their surface chemistry influences how they interact with different organs. We also demonstrate that quantitative images of the AuNPs can be generated when the appropriate tissue homogenates are chosen for matrix matching. Overall, these results demonstrate the utility of LA-ICP-MS for tracking the fate of biomedically-relevant AuNPs in vivo, facilitating the design of improved AuNP-based therapeutics.
Assuntos
Ouro/química , Ouro/metabolismo , Lasers , Nanopartículas Metálicas , Imagem Molecular/métodos , Tamanho da Partícula , Animais , Feminino , Fígado/metabolismo , Espectrometria de Massas , Camundongos , Baço/metabolismoRESUMO
The ability of nanoparticle surface functionalities to regulate immune responses during an immunological challenge (i. e. inflammation) would open new doors for their use in non-prophylactic therapeutics. We report here the use of functionalized 2 nm core gold nanoparticles to control the immunological responses of in vitro and in vivo systems presented with an inflammatory challenge. The results showed that NPs bearing a hydrophobic zwitterionic functionality boost inflammatory outcomes while hydrophilic zwitterionic NPs generate minimal immunological responses. Surprisingly, tetra(ethylene glycol) headgroups generate a significant anti-inflammatory response both in vitro and in vivo. These results demonstrate the ability of simple surface ligands to provide immunomodulatory properties, making them promising leads for the therapeutic usage of nanomaterials in diseases involving inflammation.
RESUMO
Nanoparticles (NPs) coated with a monolayer of ligands can be recognized by different components of the immune system, opening new doors for the modulation of immunological responses. By the use of different physical or chemical properties at the NP surface (such as charge, functional groups, and ligand density), NPs can be designed to have distinct cellular uptake, cytokine secretion, and immunogenicity, factors that influence the distribution and clearance of these particles. Understanding these immunological responses is critical for the development of new NP-based carriers for the delivery of therapeutic molecules, and as such several studies have been performed to understand the relationships between immune responses and NP surface functionality. In this review, we will discuss recent reports of these structure-activity relationships, and explore how these motifs can be controlled to elicit therapeutically useful immune responses.
Assuntos
Imunidade , Nanopartículas/química , Nanotecnologia/métodos , Interações Hidrofóbicas e Hidrofílicas , Propriedades de SuperfícieRESUMO
Laser desorption/ionization mass spectrometry (LDI-MS) has been used to detect gold nanoparticles (AuNPs) in biological samples, such as cells and tissues, by ionizing their attached monolayer ligands. Many NP-attached ligands, however, are difficult to ionize by LDI, making it impossible to track these NPs in biological samples. In this work, we demonstrate that concentrations of matrix-assisted LDI (MALDI) matrices an order of magnitude below the values typically used in MALDI can facilitate the selective detection of AuNPs with these ligands, even in samples as complex as cell lysate. This enhanced sensitivity arises from a synergistic relationship between the gold core and the matrix that helps to selectively ionize ligands attached to the AuNPs.
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Células/metabolismo , Ouro/análise , Nanopartículas Metálicas/análise , Células HeLa , Humanos , Estrutura Molecular , Compostos Organoáuricos/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Correlation of the surface physicochemical properties of nanoparticles with their interactions with biosystems provides key foundational data for nanomedicine. We report here the systematic synthesis of 2, 4, and 6 nm core gold nanoparticles (AuNP) featuring neutral (zwitterionic), anionic, and cationic headgroups. The cellular internalization of these AuNPs was quantified, providing a parametric evaluation of charge and size effects. Contrasting behavior was observed with these systems: with zwitterionic and anionic particles, uptake decreased with increasing AuNP size, whereas with cationic particles, uptake increased with increasing particle size. Through mechanistic studies of the uptake process, we can attribute these opposing trends to a surface-dictated shift in uptake pathways. Zwitterionic NPs are primarily internalized through passive diffusion, while the internalization of cationic and anionic NPs is dominated by multiple endocytic pathways. Our study demonstrates that size and surface charge interact in an interrelated fashion to modulate nanoparticle uptake into cells, providing an engineering tool for designing nanomaterials for specific biological applications.
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Ouro/química , Ouro/metabolismo , Nanopartículas Metálicas/química , Ânions/química , Ânions/metabolismo , Cátions/química , Cátions/metabolismo , Difusão , Endocitose , Células HeLa , Humanos , Nanopartículas Metálicas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática , Propriedades de SuperfícieRESUMO
We report herein the selective array-based detection of 30 persistent organic pollutants via cyclodextrin-promoted energy transfer. The use of three fluorophores enabled the development of an array that classified 30 analytes with 100% accuracy and identified unknown analytes with 96% accuracy, as well as identifying 92% of analytes in urine.
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Poluentes Ambientais/análise , gama-Ciclodextrinas/química , Análise Discriminante , Transferência de Energia , Monitoramento Ambiental , Poluentes Ambientais/química , Poluentes Ambientais/urina , Corantes Fluorescentes/química , HumanosRESUMO
A nanoparticle design featuring pH-responsive alkoxyphenyl acylsulfonamide ligands is reported herein. As a result of ligand structure, this nanoparticle is neutral at pHâ 7.4, becoming positively charged at tumorâ pH (<6.5). The particle uptake and cytotoxicity increase over this pHâ range. This pH-controlled uptake and toxicity makes this particle a promising tool for tumor selective therapy.
Assuntos
Ouro/química , Nanopartículas Metálicas/química , Sulfonamidas/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Íons/química , Ligantes , Nanopartículas Metálicas/toxicidadeRESUMO
Bacterial biofilms are associated with persistent infections that are resistant to conventional antibiotics and substantially complicate patient care. Surface engineered nanoparticles represent a novel, unconventional approach for disruption of biofilms and targeting of bacterial pathogens. Herein, we describe the role of surface charge of gold nanoparticles (AuNPs) on biofilm disruption and bactericidal activity towards Staphylococcus aureus and Pseudomonas aeruginosa which are important ventilator associated pneumonia (VAP) pathogens. In addition, we study the toxicity of charged AuNPs on human bronchial epithelial cells. While 100% positively charged AuNP surface was uniformly toxic to both bacteria and epithelial cells, reducing the extent of positive charge on the AuNP surface at moderate concentrations prevented epithelial cell toxicity. Reducing surface charge was however also less effective in killing bacteria. Conversely, increasing AuNP concentration while maintaining a low level of positivity continued to be bactericidal and disrupt the bacterial biofilm and was less cytotoxic to epithelial cells. These initial in vitro studies suggest that modulation of AuNP surface charge could be used to balance effects on bacteria vs. airway cells in the context of VAP, but the therapeutic window in terms of concentration vs. surface positive charge may be limited. Additional factors such as hydrophobicity may need to be considered in order to design AuNPs with specific, beneficial effects on bacterial pathogens and their biofilms.
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A new class of cationic gold nanoparticles has been synthesized bearing benzyl moieties featuring -NO2 and -OMe groups to investigate the regioisomeric control of aromatic nanoparticle-protein recognition. In general, nanoparticles bearing electron withdrawing group demonstrated higher binding affinities towards green fluorescent protein (GFP) compared to electron-donating groups. Significantly, a ~7.5 and ~4.3 fold increase in binding with GFP was observed for -NO2 groups in meta- and para-position respectively, while ortho-substitution showed similar binding compared to the unsubstituted ring. These findings demonstrated that nanoparticle-protein interaction can be controlled by the tuning the spatial orientation and the relative electronic properties of the aromatic substituents. This improved biomolecular recognition provides opportunities for enhanced biosensing and functional protein delivery to the cells.
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Identification of infectious bacteria responsible for biofilm-associated infections is challenging due to the complex and heterogeneous biofilm matrix. To address this issue and minimize the impact of heterogeneity on biofilm identification, we developed a gold nanoparticle (AuNP)-based multichannel sensor to detect and identify biofilms based on their physicochemical properties. Our results showed that the sensor can discriminate six bacterial biofilms including two composed of uropathogenic bacteria. The capability of the sensor was further demonstrated through discrimination of biofilms in a mixed bacteria/mammalian cell in vitro wound model.
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Bactérias , Biofilmes , Nanotecnologia/instrumentação , Animais , Ouro/química , Proteínas Luminescentes/química , Nanopartículas Metálicas/química , Camundongos , Células NIH 3T3 , Fatores de TempoRESUMO
Experiments and computer simulations provide a new perspective that strong correlations of counterions with charged nanoparticles can influence the localization of nanoparticles at liquid-liquid interfaces and support the formation of voltage-tunable nanoparticle arrays. We show that ion condensation onto charged nanoparticles facilitates their transport from the aqueous-side of an interface between two immiscible electrolyte solutions to the organic-side, but contiguous to the interface. Counterion condensation onto the highly charged nanoparticles overcomes the electrostatic barrier presented by the low permittivity organic material, thus providing a mechanism to transport charged nanoparticles into organic phases with implications for the distribution of nanoparticles throughout the environment and within living organisms. After transport, the nanoparticles assemble into a two-dimensional (2D) nearly close-packed array on the organic side of the interface. Voltage-tunable counterion-mediated interactions between the nanoparticles are used to control the lattice spacing of the 2D array. Tunable nanoparticle arrays self-assembled at liquid interfaces are applicable to the development of electro-variable optical devices and active elements that control the physical and chemical properties of liquid interfaces on the nanoscale.
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Low-cost diagnostics for drinking water contamination have the potential to save millions of lives. We report a method that uses inkjet printing to copattern an enzyme-nanoparticle sensor and substrate on a paper-based test strip for rapid detection of bacteria. A colorimetric response is generated on the paper substrate that allows visual detection of contamination without the need for expensive instrumentation. These strips demonstrate a viable nanomanufacturing strategy for low-cost bacterial detection.
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Bactérias/isolamento & purificação , Água Potável/análise , Nanopartículas/química , Colorimetria , Humanos , Impressão , Poluição da ÁguaRESUMO
The effects of nanoparticle (NP)-related parameters on cellular interactions are currently uncertain as analysis is complicated by the combinatorial diversity arising from the array of size, shape and surface properties. Here, we present a validated multiparametric high-content imaging method, with the utility of this approach demonstrated by in-depth analysis of the role of hydrophobicity on the interaction of Au NPs with cultured cells. In this methodology, we evaluate cell viability, membrane damage, induction of reactive oxygen species, mitochondrial health, cell area, skewness and induction of autophagy. High-content cell cycle phase studies and in-depth gene expression studies then serve to elucidate the underlying mechanisms. The data reveal a clear influence of the degree of NP surface hydrophobicity with membrane damage and autophagy induction, which is stronger than the effect of surface charge, for charges ranging between -50 and +20 mV. All labeling experiments occur in the same format, and can be further supplemented with additional parameters providing a broadly accessible format for studying cell-NP interactions under highly reproducible conditions.