Simple and robust polymer-based sensor for rapid cancer detection using serum.

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.

Regulation of Macrophage Recognition through the Interplay of Nanoparticle Surface Functionality and Protein Corona.

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.

Acylsulfonamide-Functionalized Zwitterionic Gold Nanoparticles for Enhanced Cellular Uptake at Tumor pH.

A nanoparticle design featuring pH-responsive alkoxyphenyl acylsulfonamide ligands is reported herein. As a result of ligand structure, this nanoparticle is neutral at pH 7.4, becoming positively charged at tumor pH (<6.5). The particle uptake and cytotoxicity increase over this pH range. This pH-controlled uptake and toxicity makes this particle a promising tool for tumor selective therapy.

Fabrication of corona-free nanoparticles with tunable hydrophobicity.

A protein corona is formed at the surface of nanoparticles in the presence of biological fluids, masking the surface properties of the particle and complicating the relationship between chemical functionality and biological effects. We present here a series of zwitterionic NPs of variable hydrophobicity that do not adsorb proteins at moderate levels of serum protein and do not form hard coronas at physiological serum concentrations. These particles provide platforms to evaluate nanobiological behavior such as cell uptake and hemolysis dictated directly by chemical motifs at the nanoparticle surface.

Rapid coating of surfaces with functionalized nanoparticles for regulation of cell behavior.

A robust monolayer of nanoparticles is formed via dip-coating of cell culture plates. These surfaces provide cell type-specific modulation of growth behavior without the uptake of nanoparticles.

Multiplexed imaging of nanoparticles in tissues using laser desorption/ionization mass spectrometry.

Imaging of nanomaterials in biological tissues provides vital information for the development of nanotherapeutics and diagnostics. Multiplexed imaging of different nanoparticles (NPs) greatly reduces costs, the need to use multiple animals, and increases the biodistribution information that can enhance diagnostic applications and accelerate the screening of potential therapeutics. Various approaches have been developed for imaging NPs; however, the readout of existing imaging techniques relies on specific properties of the core material or surface ligands, and these techniques are limited because of the relatively small number of NPs that can be simultaneously measured in a single experiment. Here, we demonstrate the use of laser desorption/ionization mass spectrometry (LDI-MS) in an imaging format to investigate surface chemistry dictated intraorgan distribution of NPs. This new LDI-MS imaging method enables multiplexed imaging of NPs with potentially unlimited readouts and without additional labeling of the NPs. It provides the capability to detect and image attomole levels of NPs with almost no interferences from biomolecules. Using this new imaging approach, we find that the intraorgan distributions of same-sized NPs are directly linked to their surface chemistry.

Nanoparticle-GFP "chemical nose" sensor for cancer cell identification.

Nanoparticle-based sensor arrays have been used to distinguish a wide range of bio-related molecules through pattern recognition. This "chemical nose" approach uses nanoparticles as receptors to selectively identify the analytes, while a transducer reports the binding through a readable signal (fluorescence). Here we describe a procedure that uses functionalized gold nanoparticles as receptors and green fluorescent protein (GFP) as the transducer to identify and differentiate cell state (normal, cancerous, and metastatic), an important tool in early diagnosis and treatment of tumors.

Probing novel roles of the mitochondrial uniporter in ovarian cancer cells using nanoparticles.

Nanoparticles provide a potent tool for targeting and understanding disease mechanisms. In this regard, cancer cells are surprisingly resistant to the expected toxic effects of positively charged gold nanoparticles ((+)AuNPs). Our investigations led to the identification of MICU1, regulator of mitochondrial calcium uniporter, as a key molecule conferring cancer cells with resistance to (+)AuNPs. The increase in cytosolic [Ca(2+)]cyto in malignant cells induced by (+)AuNPs is counteracted by MICU1, preventing cell death. Pharmacological or siRNA-mediated inhibition of mitochondrial Ca(+2) entry leads to endoplasmic reticulum stress and sensitizes cancer cells to (+)AuNP-induced cytotoxicity. Silencing MICU1 decreases Bcl-2 expression and increases caspase-3 activity and cytosolic cytochrome c levels, thus initiating the mitochondrial pathway for apoptosis: effects further enhanced by (+)AuNPs. This study highlights the potential of nanomaterials as a tool to broaden our understanding of cellular processes, establishes MICU1 as a novel regulator of the machinery in cancer cells that prevents apoptosis, and emphasizes the need to synergize nanoparticle design with understanding of mitochondrial machinery for enhancing targeted cellular toxicity.

Surface functionalization of nanoparticles for nanomedicine.

Control of interactions between nanoparticles and biosystems is essential for the effective utilization of these materials in biomedicine. A wide variety of nanoparticle surface structures have been developed for imaging, sensing, and delivery applications. In this research Highlight, we will emphasize advances in tailoring nanoparticle interfaces for implementation in nanomedicine.

EVALUACIÓN DE LA ACTIVIDAD CITOTÓXICA Y ANTIMICROBIANA DEL COMPUESTO [Ag(phen)2]salH) / EVALUATION OF THE CITOTOXICITY AND ANTIMICROBIAL ACTIVITY OF THE [Ag(phen)2]salH COMPOUND / AVALIAÇÂO DA ACTIVIDADE CITOTÓXICA E ANTIMICROBIANA DO COMPOSTO [Ag(phen)2]salH

En este artículo se evaluó la actividad antimicrobiana y citotóxica de un nuevo complejo de plata(I) con el ión salicilato y 1,10-fenantrolina. La caracterización de este compuesto se realizó por espectroscopia de resonancia magnética nuclear de protón y carbono-13 (RMN ¹H y 13C), espectroscopia de absorción en la región de infrarrojo (IR), análisis térmico (TG/DSC) y análisis elemental (CHN). Los resultados obtenidos a través de estos métodos sugieren la formación del compuesto con fórmula empírica [Ag(phen)2] salH. Cuando fue comparada la actividad antimicrobiana y citotóxica de este complejo con otros compuestos de plata(I) y cobre(II) de actividad conocida, se observó que el ligante 1,10-fenantrolina incrementa estas propiedades. El compuesto en estudio, presenta la mayor inhibición del crecimiento bacteriano, los microorganismos Gram positivos fueron los más susceptibles. La actividad citotóxica fue evaluada en un panel de cinco líneas celulares tumorales humanas: MDA-MB231, PC-3, HT-29, HEp-2 y A549. A las concentraciones evaluadas, el compuesto produjo una respuesta citotóxica dosis-dependiente en todas las líneas celulares tumorales, particularmente para las líneas tumorales HT-29, MDA-MB231 y A549. Todo esto, sugiere su gran potencial para usos quimioterapéuticos.

This article evaluated the antimicrobial and cytotoxic activity of a new complex of silver(I) with the salicylate ion and 1,10-phenanthroline. The characteriza-tion of this compounds was performed by nuclear magnetic resonance spectroscopy of proton and carbon-13 (RMN ¹H y 13C), spectroscopy absorption in the infrared (IR), thermal analysis (TG/DCS) and elemental analysis (CHN). The results ob-tained through these methods suggest the formation of the compound with empiri-cal formula Ag(phen)2]salH 4. When was compared the antimicrobial activity and cytotoxicity of the complex with other compounds of silver(I) and copper(II) of known activity, we observed that 1, 10-phenalthroline ligand increases these properties. The compound under study has the highest inhibition of bacterial growth, Gram-positive microorganisms were the most susceptible. The cytotoxic activity was tested against a panel of fve human cancer cell lines: MDA-MB231, PC-3, HT-29, HEp-2 and A549. At the concentrations tested, the compound pro-duced a dose-dependent cytotoxic res-ponse against all tumor cell lines, parti-cularly against the HT-29, MDA-MB231 and A549 cell lines. All this suggests its potential chemotherapeutic use.

Neste artigo avaliou-se a atividade antimicrobiana e citotóxica de um novo complexo de prata(I) com o íon sali-cilato e 1,10-fenantrolina. A caracterização deste composto foi realizada por espectroscopia de ressonância magnética nuclear de próton e carbono-13 (RMN ¹H e 13C), espectroscopia de absorção na região de infravermelho (IV), análise térmico (TG/DSC), análi-se elementar (CHN). Os resultados ob-tidos através destes métodos sugerem a formação do composto com fórmula empírica [Ag(phen)2]salH. Quando foi comparada a atividade antimicrobiana e citotóxica deste complexo com outros compostos de prata(I) e cobre(II) de ati-vidade conhecida, observou-se que o ligante 1,10-fenantrolina aumenta essas propriedades. O composto em estudo apresenta maior inibição do crescimento bacteriano, os microorganismos Gram-positivos foram os mais suscetíveis. A atividade citotóxica foi avaliada em um painel de cinco linhas de células tu-morais humanas: MDA-MB231, PC-3, HT-29, HEp-2 e A549. Com as concen-trações avaliadas, o composto deu uma resposta citotóxica dose-dependência em todas as linhagens de células tumo-rais, particularmente para as linhas de células tumorais HT-29, MDA-MB231 e A549. Tudo isso, sugere, um grande potencial para aplicações em quimioterapia.

Modulating pharmacokinetics, tumor uptake and biodistribution by engineered nanoparticles.

BACKGROUND: Inorganic nanoparticles provide promising tools for biomedical applications including detection, diagnosis and therapy. While surface properties such as charge are expected to play an important role in their in vivo behavior, very little is known how the surface chemistry of nanoparticles influences their pharmacokinetics, tumor uptake, and biodistribution. METHOD/PRINCIPAL FINDINGS: Using a family of structurally homologous nanoparticles we have investigated how pharmacological properties including tumor uptake and biodistribution are influenced by surface charge using neutral (TEGOH), zwitterionic (Tzwit), negative (TCOOH) and positive (TTMA) nanoparticles. Nanoparticles were injected into mice (normal and athymic) either in the tail vein or into the peritoneum. CONCLUSION: Neutral and zwitterionic nanoparticles demonstrated longer circulation time via both i.p. and i.v. administration, whereas negatively and positively charged nanoparticles possessed relatively short half-lives. These pharmacological characteristics were reflected on the tumor uptake and biodistribution of the respective nanoparticles, with enhanced tumor uptake by neutral and zwitterionic nanoparticles via passive targeting.