Micellar nanocontainers distribute to defined cytoplasmic organelles. Science
ABSTRACT Block copolymer micelles are water-soluble biocompatible nanocontainers with great potential for delivering hydrophobic drugs.
An understanding of their cellular distribution is essential to achieving selective delivery of drugs at the subcellular level.
Triple-labeling confocal microscopy in live cells revealed the localization of micelles in several cytoplasmic organelles,
including mitochondria, but not in the nucleus. Moreover, micelles change the cellular distribution of and increase the amount
of the agent delivered to the cells. These micelles may thus be worth exploring for their potential to selectively deliver
drugs to specified subcellular targets.
- SourceAvailable from: Ana López-Serrano
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- "Based on the current knowledge regarding the potential problems of Ag NPs for the environment and human health, there is a clear need to characterize them considering a number of important factors such as: size, chemical composition, shape, surface structure, surface charge, aggregation and solubility, and the presence or absence of other chemical functional groups. Many of these characteristics and thus, behavior, bioavailability, and toxicity are affected and modified by surrounding media properties, including pH, ionic concentration, presence of natural organic materials, colloids, etc. (Yu et al., 2013; Ferreira da Silva et al., 2011; Savic et al., 2003). Handling and sample preparation, as well as storage conditions, might be critical. "
ABSTRACT: The production of silver nanoparticles has reached nowadays high levels. Bioconcentration studies, information on persistence and toxicity are fundamental to assess their global risk and thus necessary to establish legislations regarding their use. Previous studies on silver nanoparticle toxicity have determined a clear correlation between their chemical stability and toxicity. In this work, experimental conditions able to assure silver nanoparticles stability have been optimized. Then, zebrafish (Danio rerio) eleutheroembryos were exposed to ionic silver and to Ag NPs for comparison purposes. A protocol alternative to the OECD 305 technical guideline was used. To determine silver concentration in both the eleutheroembryos and the exposure media, an analytical method consisting in ultrasound assisted extraction, followed by inductively coupled plasma mass spectrometry and graphite furnace atomic absorption spectrometry, was developed. Then, bioconcentration factors were calculated. The results revealed that ionic silver was more accumulative for zebrafish eleutheroembryos than nanoparticles at the levels tested.Environmental Pollution 05/2014; 191C:207-214. DOI:10.1016/j.envpol.2014.04.020 · 4.14 Impact Factor
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- "Well-established in vitro methods   have been introduced to determine delivery micelle stability; however, the passage of micelles through the bloodstream introduces much greater challenges due to shear forces, opsonization and uptake, and other undesirable interactions with off-target cells. It is, therefore, critical to monitor the integrity of micellar structures in vivo, preferably in real time. "
ABSTRACT: Translation of micelles from the laboratory to the clinic is limited by a poor understanding of their in vivo fate following administration. In this paper, we establish a robust approach to real-time monitoring of the in vivo stability of micelles using Förster Resonance Energy Transfer (FRET). This characterization method allows for exquisite insight into the fate of micellar constituents, affording the capabilities to rapidly and efficiently evaluate a library of synthetically derived micellar systems as new therapeutic platforms in vivo. FRET-enabled biological characterization further holds potential to tailor material systems being uniquely investigated across the delivery community towards the next generation of stable therapeutics for disease management.Biomaterials 01/2014; 35(11). DOI:10.1016/j.biomaterials.2014.01.027 · 8.31 Impact Factor
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- "Finally, although it was not tested in the present study, the cardiac effects of AF-SWCNTs could have been mediated through nanotubeinduced oxidative stress. It has been demonstrated that nanoparticles preferentially mobilize to mitochondria (Savic et al., 2003). In addition, pulmonary exposure to SWCNTs has been associated with oxidative vascular damage in wild type mice, as well as accelerated atherosclerosis in ApoE −/− transgenic mice in the absence of systemic inflammation (Li et al., 2007). "
ABSTRACT: Engineered carbon nanotubes are being developed for a wide range of industrial and medical applications. Because of their unique properties, nanotubes can impose potentially toxic effects, particularly if they have been modified to express functionally reactive chemical groups on their surface. The present study was designed to evaluate whether acid functionalization (AF) enhanced the cardiopulmonary toxicity of single-walled carbon nanotubes (SWCNT) as well as control carbon black particles. Mice were exposed by oropharyngeal aspiration to 10 or 40 μg of saline-suspended single-walled carbon nanotubes (SWCNTs), acid-functionalized SWCNTs (AF-SWCNTs), ultrafine carbon black (UFCB), AF-UFCB, or 2 μg LPS. 24 hours later, pulmonary inflammatory responses and cardiac effects were assessed by bronchoalveolar lavage and isolated cardiac perfusion respectively, and compared to saline or LPS-instilled animals. Additional mice were assessed for histological changes in lung and heart. Instillation of 40 μg of AF-SWCNTs, UFCB and AF-UFCB increased percentage of pulmonary neutrophils. No significant effects were observed at the lower particle concentration. Sporadic clumps of particles from each treatment group were observed in the small airways and interstitial areas of the lungs according to particle dose. Patches of cellular infiltration and edema in both the small airways and in the interstitium were also observed in the high dose group. Isolated perfused hearts from mice exposed to 40 μg of AF-SWCNTs had significantly lower cardiac functional recovery, greater infarct size, and higher coronary flow rate than other particle-exposed animals and controls, and also exhibited signs of focal cardiac myofiber degeneration. No particles were detected in heart tissue under light microscopy. This study indicates that while acid functionalization increases the pulmonary toxicity of both UFCB and SWCNTs, this treatment caused cardiac effects only with the AF-carbon nanotubes. Further experiments are needed to understand the physico-chemical processes involved in this phenomenon.Toxicology and Applied Pharmacology 07/2013; 239(3):224-232. DOI:10.1016/j.taap.2009.05.019 · 3.63 Impact Factor