Journal Of Nanomedicine & Nanotechnology[JOURNAL]
Sun
168 papers
Cell membrane conformation at vertical nanowire array interface revealed by fluorescence imaging.
Berthing T, Bonde S, Rostgaard KR … +4 more , Madsen MH, Sørensen CB, Nygård J, Martinez KL
Nanotechnology · 2012 Oct · PMID 23010859 · Publisher ↗
The perspectives offered by vertical arrays of nanowires for biosensing applications in living cells depend on the access of individual nanowires to the cell interior. Recent results on electrical access and molecular de...
The perspectives offered by vertical arrays of nanowires for biosensing applications in living cells depend on the access of individual nanowires to the cell interior. Recent results on electrical access and molecular delivery suggest that direct access is not always obtained. Here, we present a generic approach to directly visualize the membrane conformation of living cells interfaced with nanowire arrays, with single nanowire resolution. The method combines confocal z-stack imaging with an optimized cell membrane labelling strategy which was applied to HEK293 cells interfaced with 2-11 μm long and 3-7 μm spaced nanowires with various surface coatings (bare, aminosilane-coated or polyethyleneimine-coated indium arsenide). We demonstrate that, for all commonly used nanowire lengths, spacings and surface coatings, nanowires generally remain enclosed in a membrane compartment, and are thereby not in direct contact with the cell interior.
Mechanism of co-nanoprecipitation of organic actives and block copolymers in a microfluidic environment.
Capretto L, Cheng W, Carugo D … +3 more , Katsamenis OL, Hill M, Zhang X
Nanotechnology · 2012 Sep · PMID 22922560 · Publisher ↗
Microreactors have been shown to be a powerful tool for the production of nanoparticles (NPs); however, there is still a lack of understanding of the role that the microfluidic environment plays in directing the nanoprec...
Microreactors have been shown to be a powerful tool for the production of nanoparticles (NPs); however, there is still a lack of understanding of the role that the microfluidic environment plays in directing the nanoprecipitation process. Here we investigate the mechanism of nanoprecipitation of block copolymer stabilized organic NPs using a microfluidic-based reactor in combination with computational fluid dynamics (CFD) modelling of the microfluidic implementation. The latter also accounts for the complex interplay between molecular and hydrodynamic phenomena during the nanoprecipitation process, in order to understand the hydrodynamics and its influence on the NP formation process. It is demonstrated that the competitive reactions result in the formation of two types of NPs, i.e., either with or without loading organic actives. The obtained results are interpreted by taking into consideration a new parameter representing the mismatching between the aggregations of the polymers and actives, which plays a decisive role in determining the size and polydispersity of the prepared hybrid NPs. These results expand the current understanding of the co-nanoprecipitation mechanism of active and block copolymer stabilizer, and on the role exerted by the microfluidic environment, giving information that could be translated to the emerging fields of microfluidic formation of NPs and nanomedicine.
Rationally designed oxaliplatin-nanoparticle for enhanced antitumor efficacy.
Paraskar A, Soni S, Roy B … +2 more , Papa AL, Sengupta S
Nanotechnology · 2012 Feb · PMID 22275055 · Full text
Nanoscale drug delivery vehicles have been extensively studied as carriers for cancer chemotherapeutics. However, the formulation of platinum chemotherapeutics in nanoparticles has been a challenge arising from their phy...
Nanoscale drug delivery vehicles have been extensively studied as carriers for cancer chemotherapeutics. However, the formulation of platinum chemotherapeutics in nanoparticles has been a challenge arising from their physicochemical properties. There are only a few reports describing oxaliplatin nanoparticles. In this study, we derivatized the monomeric units of a polyisobutylene maleic acid copolymer with glucosamine, which chelates trans-1,2-diaminocyclohexane (DACH) platinum (II) through a novel monocarboxylato and O --> Pt coordination linkage. At a specific polymer to platinum ratio, the complex self-assembled into a nanoparticle, where the polymeric units act as the leaving group, releasing DACH-platinum in a sustained pH-dependent manner. Sizing was done using dynamic light scatter and electron microscopy. The nanoparticles were evaluated for efficacy in vitro and in vivo. Biodistribution was quantified using inductively coupled plasma atomic absorption spectroscopy (ICP-AAS). The PIMA-GA-DACH-platinum nanoparticle was found to be more active than free oxaliplatin in vitro. In vivo, the nanoparticles resulted in greater tumor inhibition than oxaliplatin (equivalent to 5 mg kg⁻¹ platinum dose) with minimal nephrotoxicity or body weight loss. ICP-AAS revealed significant preferential tumor accumulation of platinum with reduced biodistribution to the kidney or liver following PIMA-GA-DACH-platinum nanoparticle administration as compared with free oxaliplatin. These results indicate that the rational engineering of a novel polymeric nanoparticle inspired by the bioactivation of oxaliplatin results in increased antitumor potency with reduced systemic toxicity compared with the parent cytotoxic. Rational design can emerge as an exciting strategy in the synthesis of nanomedicines for cancer chemotherapy.
Fluorescent-magnetic dual-encoded nanospheres: a promising tool for fast-simultaneous-addressable high-throughput analysis.
Xie M, Hu J, Wen CY … +3 more , Zhang ZL, Xie HY, Pang DW
Nanotechnology · 2012 Jan · PMID 22173487 · Publisher ↗
Bead-based optical encoding or magnetic encoding techniques are promising in high-throughput multiplexed detection and separation of numerous species under complicated conditions. Therefore, a self-assembly strategy impl...
Bead-based optical encoding or magnetic encoding techniques are promising in high-throughput multiplexed detection and separation of numerous species under complicated conditions. Therefore, a self-assembly strategy implemented in an organic solvent is put forward to fabricate fluorescent-magnetic dual-encoded nanospheres. Briefly, hydrophobic trioctylphosphine oxide-capped CdSe/ZnS quantum dots (QDs) and oleic acid-capped nano-γ-Fe2O3 magnetic particles are directly, selectively and controllably assembled on branched poly(ethylene imine)-coated nanospheres without any pretreatment, which is crucial to keep the high quantum yield of QDs and good dispersibility of γ-Fe2O3. Owing to the tunability of coating amounts of QDs and γ-Fe2O3 as well as controllable fluorescent emissions of deposited-QDs, dual-encoded nanospheres with different photoluminescent emissions and gradient magnetic susceptibility are constructed. Using this improved layer-by-layer self-assembly approach, deposition of hydrophobic nanoparticles onto hydrophilic carriers in organic media can be easily realized; meanwhile, fluorescent-magnetic dual-functional nanospheres can be further equipped with readable optical and magnetic addresses. The resultant fluorescent-magnetic dual-encoded nanospheres possess both the unique optical properties of QDs and the superparamagnetic properties of γ-Fe2O3, exhibiting good monodispersibility, huge encoding capacity and nanoscale particle size. Compared with the encoded microbeads reported by others, the nanometre scale of the dual-encoded nanospheres gives them minimum steric hindrance and higher flexibility.
Cytoprotective properties of a fullerene derivative against copper.
Ratnikova TA, Bebber MJ, Huang G … +2 more , Larcom LL, Ke PC
Nanotechnology · 2011 Oct · PMID 21896981 · Publisher ↗
To delineate the complexity of the response of cells to nanoparticles we have performed a study on HT-29 human colon carcinoma cells exposed first to a fullerene derivative C(60)(OH)(20) and then to physiological copper...
To delineate the complexity of the response of cells to nanoparticles we have performed a study on HT-29 human colon carcinoma cells exposed first to a fullerene derivative C(60)(OH)(20) and then to physiological copper ions. Our cell viability, proliferation, and intracellular reactive oxygen species (ROS) production assays clearly indicated that C(60)(OH)(20) suppressed cell damage as well as ROS production induced by copper, probably through neutralization of the metal ions by C(60)(OH)(20) in the extracellular space, as well as by adsorption and uptake of the nanoparticles surface-modified by the biomolecular species in the cell medium. This double-exposure study provides new data on the effects of nanoparticles on cell metabolism and may aid the treatment of oxidant-mediated diseases using nanomedicine.
Shape-controlled synthesis of NIR absorbing branched gold nanoparticles and morphology stabilization with alkanethiols.
Van de Broek B, Frederix F, Bonroy K … +4 more , Jans H, Jans K, Borghs G, Maes G
Nanotechnology · 2011 Jan · PMID 21135459 · Publisher ↗
Gold nanoparticles are ideal candidates for clinical applications if their plasmon absorption band is situated in the near infrared region (NIR) of the electromagnetic spectrum. Various parameters, including the nanopart...
Gold nanoparticles are ideal candidates for clinical applications if their plasmon absorption band is situated in the near infrared region (NIR) of the electromagnetic spectrum. Various parameters, including the nanoparticle shape, strongly influence the position of this absorption band. The aim of this study is to produce stabilized NIR absorbing branched gold nanoparticles with potential for biomedical applications. Hereto, the synthesis procedure for branched gold nanoparticles is optimized varying the different synthesis parameters. By subsequent electroless gold plating the plasmon absorption band is shifted to 747.2 nm. The intrinsic unstable nature of the nanoparticles' morphology can be clearly observed by a spectral shift and limits their use in real applications. However, in this article we show how the stabilization of the branched structure can be successfully achieved by exchanging the initial capping agent for different alkanethiols and disulfides. Furthermore, when using alkanethiols/disulfides with poly(ethylene oxide) units incorporated, an increased stability of the gold nanoparticles is achieved in high salt concentrations up to 1 M and in a cell culture medium. These achievements open a plethora of opportunities for these stabilized branched gold nanoparticles in nanomedicine.
C60(Nd) nanoparticles enhance chemotherapeutic susceptibility of cancer cells by modulation of autophagy.
Wei P, Zhang L, Lu Y … +2 more , Man N, Wen L
Nanotechnology · 2010 Dec · PMID 21071824 · Publisher ↗
Autophagy, an evolutionally conserved intracellular process degrading cytoplasmic proteins and organelles for recycling, has become one of the most remarkable strategies applied in cancer research. The fullerene C60 nano...
Autophagy, an evolutionally conserved intracellular process degrading cytoplasmic proteins and organelles for recycling, has become one of the most remarkable strategies applied in cancer research. The fullerene C60 nanoparticle (nC60) has been shown to induce autophagy and sensitize chemotherapeutic killing of cancer cells, but the details still remain unknown. Here we show that a water-dispersed nanoparticle solution of derivatized fullerene C60, C60(Nd) nanoparticles (nC60(Nd)), has greater potential in inducing autophagy and sensitizing chemotherapeutic killing of both normal and drug-resistant cancer cells than nC60 does in an autophagy-dependent fashion. Additionally we further demonstrated that autophagy induced by nC60/C60(Nd) and Rapamycin had completely different roles in cancer chemotherapy. Our results, for the first time, revealed a novel and more potent derivative of the C60 nanoparticle in enhancing the cytotoxicity of chemotherapeutic agents and reducing drug resistance through autophagy modulation, which may ultimately lead to novel therapeutic strategies in cancer therapy.
Synthesis and applications of magnetic nanoparticles for biorecognition and point of care medical diagnostics.
Sandhu A, Handa H, Abe M
Nanotechnology · 2010 Nov · PMID 20935358 · Publisher ↗
Functionalized magnetic nanoparticles are important components in biorecognition and medical diagnostics. Here, we present a review of our contribution to this interdisciplinary research field. We start by describing a s...
Functionalized magnetic nanoparticles are important components in biorecognition and medical diagnostics. Here, we present a review of our contribution to this interdisciplinary research field. We start by describing a simple one-step process for the synthesis of highly uniform ferrite nanoparticles (d = 20-200 nm) and their functionalization with amino acids via carboxyl groups. For real-world applications, we used admicellar polymerization to produce 200 nm diameter 'FG beads', consisting of several 40 nm diameter ferrite nanoparticles encapsulated in a co-polymer of styrene and glycidyl methacrylate for high throughput molecular screening. The highly dispersive FG beads were functionalized with an ethylene glycol diglycidyl ether spacer and used for affinity purification of methotrexate-an anti-cancer agent. We synthesized sub-100 nm diameter magnetic nanocapsules by exploiting the self-assembly of viral capsid protein pentamers, where single 8, 20, and 27 nm nanoparticles were encapsulated with VP1 pentamers for applications including MRI contrast agents. The FG beads are now commercially available for use in fully automated bio-screening systems. We also incorporated europium complexes inside a polymer matrix to produce 140 nm diameter fluorescent-ferrite beads (FF beads), which emit at 618 nm. These FF beads were used for immunofluorescent staining for diagnosis of cancer metastases to lymph nodes during cancer resection surgery by labeling tumor cell epidermal growth factor receptor (EGFRs), and for the detection of brain natriuretic peptide (BNP)-a hormone secreted in excess amounts by the heart when stressed-to a level of 2.0 pg ml(-1). We also describe our work on Hall biosensors made using InSb and GaAs/InGaAs/AlGaAs 2DEG heterostructures integrated with gold current strips to reduce measurement times. Our approach for the detection of sub-200 nm magnetic bead is also described: we exploit the magnetically induced capture of micrometer sized 'probe beads' by nanometer sized 'target beads', enabling the detection of small concentrations of beads as small as 8 nm in 'pumpless' microcapillary systems. Finally, we describe a 'label-less homogeneous' procedure referred to as 'magneto-optical transmission (MT) sensing', where the optical transmission of a solution containing rotating linear chains of magnetic nanobeads was used to detect biomolecules with pM-level sensitivity with a dynamic range of more than four orders of magnitude. Our research on the synthesis and applications of nanoparticles is particularly suitable for point of care diagnostics.
Fabrication and characterization of an inorganic gold and silica nanoparticle mediated drug delivery system for nitric oxide.
Das A, Mukherjee P, Singla SK … +5 more , Guturu P, Frost MC, Mukhopadhyay D, Shah VH, Patra CR
Nanotechnology · 2010 Jul · PMID 20610873 · Full text
Nitric oxide (NO) plays an important role in inhibiting the development of hepatic fibrosis and its ensuing complication of portal hypertension by inhibiting human hepatic stellate cell (HSC) activation. Here we have dev...
Nitric oxide (NO) plays an important role in inhibiting the development of hepatic fibrosis and its ensuing complication of portal hypertension by inhibiting human hepatic stellate cell (HSC) activation. Here we have developed a gold nanoparticle and silica nanoparticle mediated drug delivery system containing NO donors, which could be used for potential therapeutic application in chronic liver disease. The gold nanoconjugates were characterized using several physico-chemical techniques such as UV-visible spectroscopy and transmission electron microscopy. Silica nanoconjugates were synthesized and characterized as reported previously. NO released from gold and silica nanoconjugates was quantified under physiological conditions (pH = 7.4 at 37 degrees C) for a substantial period of time. HSC proliferation and the vascular tube formation ability, manifestations of their activation, were significantly attenuated by the NO released from these nanoconjugates. This study indicates that gold and silica nanoparticle mediated drug delivery systems for introducing NO could be used as a strategy for the treatment of hepatic fibrosis or chronic liver diseases, by limiting HSC activation.
Homologous RBC-derived vesicles as ultrasmall carriers of iron oxide for magnetic resonance imaging of stem cells.
Chang M, Hsiao JK, Yao M … +8 more , Chien LY, Hsu SC, Ko BS, Chen ST, Liu HM, Chen YC, Yang CS, Huang DM
Nanotechnology · 2010 Jun · PMID 20479509 · Publisher ↗
Ultrasmall superparamagnetic iron oxide (USPIO) particles are very useful for cellular magnetic resonance imaging (MRI), which plays a key role in developing successful stem cell therapies. However, their low intracellul...
Ultrasmall superparamagnetic iron oxide (USPIO) particles are very useful for cellular magnetic resonance imaging (MRI), which plays a key role in developing successful stem cell therapies. However, their low intracellular labeling efficiency, and biosafety concerns associated with their use, have limited their potential usage. In this study we develop a novel system composed of RBC-derived vesicles (RDVs) for efficient delivery of USPIO particles into human bone marrow mesenchymal stem cells (MSCs) for cellular MRI in vitro and in vivo. RDVs are highly biosafe to their autologous MSCs as manifested by cell viability, differentiation, and gene microarray assays. The data demonstrate the potential of RDVs as intracellular delivery vehicles for biomedical applications.
RNAi nanomedicines: challenges and opportunities within the immune system.
Weinstein S, Peer D
Nanotechnology · 2010 Jun · PMID 20463388 · Publisher ↗
RNAi, as a novel therapeutic modality, has an enormous potential to bring the era of personalized medicine one step further from notion into reality. However, delivery of RNAi effector molecules into their target tissues...
RNAi, as a novel therapeutic modality, has an enormous potential to bring the era of personalized medicine one step further from notion into reality. However, delivery of RNAi effector molecules into their target tissues and cells remain extremely challenging. Major attempts have been made in recent years to develop sophisticated nanocarriers that could overcome these hurdles. This review will present the recent progress with the challenges and opportunities in this emerging field, focusing mostly on the in vivo applications with special emphasis on the strategies for RNAi delivery into immune cells.
Long-term follow-up of lung biodistribution and effect of instilled SWCNTs using multiscale imaging techniques.
Al Faraj A, Bessaad A, Cieslar K … +3 more , Lacroix G, Canet-Soulas E, Crémillieux Y
Nanotechnology · 2010 Apr · PMID 20368681 · Publisher ↗
Due to their distinctive properties, single-walled carbon nanotubes (SWCNTs) are being more and more extensively used in nanotechnology, with prospects in nanomedicine. It would therefore appear essential to develop and...
Due to their distinctive properties, single-walled carbon nanotubes (SWCNTs) are being more and more extensively used in nanotechnology, with prospects in nanomedicine. It would therefore appear essential to develop and apply appropriate imaging tools for detecting and evaluating their biological impacts with the prospect of medical applications or in the situation of accidental occupational exposure. It has been shown recently that raw SWCNTs with metallic impurities can be noninvasively detected in the lungs by hyperpolarized (3)helium (HP-(3)He) MRI. Moreover raw and purified SWCNTs had no acute biological effect. The purpose of the present longitudinal study was to investigate long-term follow-up by imaging, as well as chronic lung effects. In a 3-month follow-up study, multiscale imaging techniques combining noninvasive HP-(3)He and proton (H) MRI to ex vivo light (histopathological analysis) and transmission electron microscopy (TEM) were used to assess the biodistribution and biological effects of intrapulmonary instilled raw SWCNTs. Specific in vivo detection of carbon nanotubes with MRI relied on their intrinsic metal impurities. MRI also has the ability to evaluate tissue inflammation by the follow-up of local changes in signal intensity. MRI and ex vivo microscopy techniques showed that granulomatous and inflammatory reactions were produced in a time and dose dependent manner by instilled raw SWCNTs.
Lithographically defined uniform worm-shaped polymeric nanoparticles.
Tao L, Zhao XM, Gao JM … +1 more , Hu W
Nanotechnology · 2010 Mar · PMID 20110578 · Publisher ↗
We report a nanoimprint lithography method combined with photolithography on a bi-layer polymer setup to define nano-worms laterally in nano-gratings and produce uniform worm-shaped polymeric nanoparticles in aqueous sol...
We report a nanoimprint lithography method combined with photolithography on a bi-layer polymer setup to define nano-worms laterally in nano-gratings and produce uniform worm-shaped polymeric nanoparticles in aqueous solution by dissolving water soluble sacrificial layer poly(vinyl alcohol) (PVA). Process control of the thin residue layer, SU-8 curing using broadband UV source, and warm development to remove any residue are necessary to ensure success of this technique. The use of water soluble PVA as a releasing layer and elimination of an invasive plasma etching for the releasing process makes this protocol highly compatible with biomaterials. Direct release and suspension of fluorescent worm-shaped nanoparticles (length to width ratio up to 75) in aqueous solution were demonstrated. Compared to the worm-shaped nanoparticles made by self-assembly, these lithographically defined nano-worms have much better controllability and uniformity on the shape, size, and aspect ratio. The availability of these precisely defined non-spherical particles would be important to develop a comprehensive understanding of the shape effects of nanoparticles on their efficacy in nanomedicine applications.
Effect of Fe(3)O(4) magnetic nanoparticles on lysozyme amyloid aggregation.
Bellova A, Bystrenova E, Koneracka M … +7 more , Kopcansky P, Valle F, Tomasovicova N, Timko M, Bagelova J, Biscarini F, Gazova Z
Nanotechnology · 2010 Feb · PMID 20061598 · Publisher ↗
Peptide amyloid aggregation is a hallmark of several human pathologies termed amyloid diseases. We have investigated the effect of electrostatically stabilized magnetic nanoparticles of Fe(3)O(4) on the amyloid aggregati...
Peptide amyloid aggregation is a hallmark of several human pathologies termed amyloid diseases. We have investigated the effect of electrostatically stabilized magnetic nanoparticles of Fe(3)O(4) on the amyloid aggregation of lysozyme, as a prototypical amyloidogenic protein. Thioflavin T fluorescence assay and atomic force microscopy were used for monitoring the inhibiting and disassembly activity of magnetic nanoparticles of Fe(3)O(4). We have found that magnetic Fe(3)O(4) nanoparticles are able to interact with lysozyme amyloids in vitro leading to a reduction of the amyloid aggregates, thus promoting depolymerization; the studied nanoparticles also inhibit lysozyme amyloid aggregation. The ability to inhibit lysozyme amyloid formation and promote lysozyme amyloid disassembly exhibit concentration-dependent characteristics with IC50 = 0.65 mg ml(-1) and DC50 = 0.16 mg ml(-1) indicating that nanoparticles interfere with lysozyme aggregation already at stoichiometric concentrations. These features make Fe(3)O(4) nanoparticles of potential interest as therapeutic agents against amyloid diseases and their non-risk exploitation in nanomedicine and nanodiagnostics.
Delivery of paclitaxel by physically loading onto poly(ethylene glycol) (PEG)-graft-carbon nanotubes for potent cancer therapeutics.
Lay CL, Liu HQ, Tan HR … +1 more , Liu Y
Nanotechnology · 2010 Feb · PMID 20057024 · Publisher ↗
UNLABELLED: Physically loading of paclitaxel (PTX) onto carbon nanotubes (CNTs) is achieved through immersion of poly(ethylene glycol) (PEG)-graft-single walled CNTs (PEG-g-SWNTs) or PEG-graft-multi-walled CNTs (PEG-g-MW...
UNLABELLED: Physically loading of paclitaxel (PTX) onto carbon nanotubes (CNTs) is achieved through immersion of poly(ethylene glycol) (PEG)-graft-single walled CNTs (PEG-g-SWNTs) or PEG-graft-multi-walled CNTs (PEG-g-MWNTs) in a saturated solution of PTX in methanol. After loading once the loading capacity (LD%) is 26% (w/w) and 36% (w/w) for PEG-g-SWNTs or PEG-g-MWNTs, respectively. With these PTX contents, PTX loaded PEG-g-SWNTs and PTX loaded PEG-g-MWNTs still have good dispersity in aqueous solution and individual CNTs can be observed in TEM images. PTX can be released from PEG-g-CNTs several times faster than from free PTX but still in a sustained profile with less than 40% of PTX being released in 40 days at pH 7 or 5. In vitro cytotoxicity of samples is evaluated in HeLa cells and MCF-7 cells. PEG-g-SWNTs and PEG-g-MWNTs show low cytotoxicity in both cells with insignificant effects on the cell proliferation rates. However, both PTX loaded PEG-g-SWNTs and PTX loaded PEG-g-MWNTs show high efficacy to kill HeLa cells and MCF-7 cells, as reflected by IC(50) lower than free PTX. Therefore, PTX loaded PEG-g-CNTs are promising for cancer therapeutics. KEYWORDS: carbon nanotubes, poly(ethylene glycol), drug delivery, cancer therapy, nanomedicine.
Incorporation of liquid lipid in lipid nanoparticles for ocular drug delivery enhancement.
Shen J, Sun M, Ping Q … +2 more , Ying Z, Liu W
Nanotechnology · 2010 Jan · PMID 19955616 · Publisher ↗
The present work investigates the effect of liquid lipid incorporation on the physicochemical properties and ocular drug delivery enhancement of nanostructured lipid carriers (NLCs) and attempts to elucidate in vitro and...
The present work investigates the effect of liquid lipid incorporation on the physicochemical properties and ocular drug delivery enhancement of nanostructured lipid carriers (NLCs) and attempts to elucidate in vitro and in vivo the potential of NLCs for ocular drug delivery. The CyA-loaded or fluorescein-marked nanocarriers composed of Precifac ATO 5 and Miglyol 840 (as liquid lipid) were prepared by melting-emulsion technology, and the physicochemical properties of nanocarriers were determined. The uptake of nanocarriers by human corneal epithelia cell lines (SDHCEC) and rabbit cornea was examined. Ex vivo fluorescence imaging was used to investigate the ocular distribution of nanocarriers. The in vitro cytotoxicity and in vivo acute tolerance were evaluated. The higher drug loading capacity and improved in vitro sustained drug release behavior of lipid nanoparticles was found with the incorporation of liquid lipid in lipid nanoparticles. The uptake of nanocarriers by the SDHCEC was increased with the increase in liquid lipid loading. The ex vivo fluorescence imaging of the ocular tissues indicated that the liquid lipid incorporation could improve the ocular retention and penetration of ocular therapeutics. No alternation was macroscopically observed in vivo after ocular surface exposure to nanocarriers. These results indicated that NLC was a biocompatible and potential nanocarrier for ocular drug delivery enhancement.
Single-walled carbon nanotube-conjugated chemotherapy exhibits increased therapeutic index in melanoma.
Chaudhuri P, Soni S, Sengupta S
Nanotechnology · 2010 Jan · PMID 19955607 · Publisher ↗
The incidence of malignant melanoma is increasing at an alarming rate globally. Poor prognosis and extraordinarily low survival rates of malignant melanoma necessitates the development of new chemotherapeutic strategies....
The incidence of malignant melanoma is increasing at an alarming rate globally. Poor prognosis and extraordinarily low survival rates of malignant melanoma necessitates the development of new chemotherapeutic strategies. An emerging approach is to harness nanotechnology to optimize the existing chemotherapies. In the present study we have demonstrated that the delivery of doxorubicin using a nanotechnology-based platform significantly reduces the systemic toxicity of the drug, keeping unchanged its therapeutic efficacy in a mouse melanoma tumor model. Specifically we modified single-walled carbon nanotubes (CNTs) to conjugate a doxorubicin prodrug via a carbamate linker that cleaves enzymatically to cause temporal release of the active drug. The CNT-doxorubicin conjugate (CNT-Dox) induced time-dependent cell death in B16-F10 melanoma cells in vitro. The nanoparticle was rapidly internalized into the lysosome of melanoma cells and was retained in the subcellular compartment for over 24 h. In an in vivo melanoma model, treatment with the nanotube-doxorubicin conjugate abrogated tumor growth without the systemic side-effects associated with free doxorubicin. Our studies demonstrate that a simple and versatile CNT-based nanovector can be harnessed for the delivery of chemotherapy to melanoma, with increased therapeutic index.
Shaping nano-/micro-particles for enhanced vascular interaction in laminar flows.
Lee SY, Ferrari M, Decuzzi P
Nanotechnology · 2009 Dec · PMID 19904027 · Publisher ↗
Non-spherical nano-/micro-particles can drift laterally (hydrodynamic margination) in a linear laminar flow under the concurrent effect of hydrodynamic and inertial forces. Such a feature can be exploited in the rational...
Non-spherical nano-/micro-particles can drift laterally (hydrodynamic margination) in a linear laminar flow under the concurrent effect of hydrodynamic and inertial forces. Such a feature can be exploited in the rational design of particle-based intravascular and pulmonary delivery systems and for designing new flow fractioning systems for high-throughput particle separation. A general approach is presented to predict the marginating behavior of non-spherical particles. The lateral drift velocity is shown to depend on the particle Stokes number St(a) and to grow with the size, density and rotational inertia of the particle. Elongated particles, in particular, low aspect ratio discoidal particles, exhibit the largest propensity to marginate in a linear laminar flow. In the blood microcirculation, at low shear rates (S<100 s(-1)), non-spherical particles oscillate around their trajectory and margination can only be achieved through the application of external force fields (gravitational, magnetic); whereas for larger S (100 s(-1)<S<10(4) s(-1)), micrometer particles can achieve drift velocities in the order of 1-10 microm s(-1). In the pulmonary circulation, hydrodynamic margination can be observed even for sub-micrometer particles. Finally, the inherent propensity of non-spherical particles to drift laterally can be effectively exploited for designing microfluidic devices, based on the flow fractioning approach, for particle separation without using external lateral force fields.
Direct observation of the binding process between protein and quantum dots by in situ surface plasmon resonance measurements.
Xiao Q, Zhou B, Huang S … +6 more , Tian F, Guan H, Ge Y, Liu X, He Z, Liu Y
Nanotechnology · 2009 Aug · PMID 19620762 · Publisher ↗
A layer-by-layer surface decoration technique has been developed to anchor quantum dots (QDs) onto a gold substrate and an in situ surface plasmon resonance technique has been used to study interactions between the QDs a...
A layer-by-layer surface decoration technique has been developed to anchor quantum dots (QDs) onto a gold substrate and an in situ surface plasmon resonance technique has been used to study interactions between the QDs and different proteins. Direct observation of the binding of the protein onto the QDs and the kinetics of the adsorption and dissociation of different proteins on the QDs has been achieved. This would be helpful for the identification of particle-associated proteins and may offer a fundamental prerequisite for nanobiology, nanomedicine and nanotoxicology. The combination of the novel layer-by-layer surface modification method and in situ surface plasmon resonance would be powerful in studying biological systems such as DNA and cells.
Cell nanomechanics and focal adhesions are regulated by retinol and conjugated linoleic acid in a dose-dependent manner.
Silberberg YR, Yakubov GE, Horton MA … +1 more , Pelling AE
Nanotechnology · 2009 Jul · PMID 19546491 · Publisher ↗
Retinol and conjugated linoleic acid (CLA) have previously been shown to have an important role in gene expression and various cellular processes, including differentiation, proliferation and cell death. In this study we...
Retinol and conjugated linoleic acid (CLA) have previously been shown to have an important role in gene expression and various cellular processes, including differentiation, proliferation and cell death. In this study we have investigated the effect of retinol and CLA, both individually and in combination, on the intracellular cytoskeleton, focal adhesions (FAs) and the nanomechanical properties of 3T3 fibroblasts. We observed a dose-dependent decrease in the formation of FAs following treatment with either compound, which was directly correlated to an increase in cell height (>30%) and a decrease in the measured Young's modulus (approximately 28%). Furthermore, treatments with both compounds demonstrated an increased effect and led to a reduction of >70% in the average number of FAs per cell and a decrease of >50% in average cell stiffness. These data reveal that retinol and CLA disrupt FA formation, leading to an increase in cell height and a significant decrease in stiffness. These results may broaden our understanding of the interplay between cell nanomechanics and cellular contact with the external microenvironment, and help to shed light on the important role of retinoids and CLA in health and disease.
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