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Magnetic drug targeting envisions the use of external magnets to manipulate magnetic particles inside the human body, to direct them to disease targets such as tumors, infections, and ear and eye targets. A key question is how good are the particles? How well do they move in media under the action of applied magnetic gradients? To address this question, we designed and implemented a simple on-chip testing and image tracking system to quantitatively assess the motion of magnetic particles in response to an applied magnetic gradient. In this system, the magnetic particles are placed in on-chip wells and then a calibrated magnetic gradient is applied to the particles. The resulting motion of the particles is monitored and quantified by a microscope, camera, and by imaging software. The system measures both particle speed and chaining. We assessed the motion of seven different commercial magnetic particle ranging in size from 10 nm to 100 μm in diameter. All seven particles displayed consistent trends: larger particles moved faster (according to a power law), particles at higher concentrations created longer chains or needle-like aggregates and moved faster, and both speed and chain or needle length increased with time yielding a final speed proportional to the square of particle diameter. The most striking finding was the consistency of all seven particles within these trends. There were no outliers. No particles performed above the trend lines (no high-performance outliers), nor were there any particles that performed below the trend line (no poor performance outliers). We hope the data collected can be used to better understand particle motion, including the physics of chaining and how it impacts the speed of particle transport in media, and will enable improved design of next-generation magnetic drug delivery systems.

This paper investigates the safety of a novel ‘magnetic injection’ method of delivering therapy to the cochlea, in a rodent model. In this method of administration, a magnetic field is employed to actively transport drug-eluting superparamagnetic iron-oxide core nanoparticles into the cochlea, where they then release their drug payload (we delivered the steroid prednisolone). Our study design and selection of control groups was based on published regulatory guidance for safety studies that involve local drug delivery. We tested for both single and multiple delivery doses to the cochlea, and found that magnetic delivery did not harm hearing. There was no statistical difference in hearing between magnetically treated ears versus ears that received intra-tympanic steroid (a mimic of a standard-of-care for sudden sensorineural hearing loss), both 2 and 30 days after treatment. Since our treatment is local to the ear, the levels of steroid and iron circulating systemically after our treatment were low, below mass-spectrometry detection limits for the steroid and no different from normal for iron. No adverse findings were observed in ear tissue histopathology or in animal gross behavior. At 2 and 30 days after treatment, inflammatory changes examined in the ear were limited to the middle ear, were very mild in severity, and by day 90 there was ongoing and almost complete reversibility of these changes. There were no ear tissue scarring or hemorrhage trends associated with magnetic delivery. In summary, after conducting a pre-clinical safety study, no adverse safety issues were observed.

Delivery of therapy to the cochlea is a challenge and limits the efficacy of therapies meant to treat hearing loss, reverse tinnitus, and protect hearing from chemotherapy regimens. Magnetic injection is a technique that uses magnetic fields to inject nanoparticles from the middle ear into the cochlea, where they can then elute therapy to treat hearing disorders. To evaluate the safety of this treatment in the middle ear, 30 rats were subdivided into 6 groups and treated by single or multiple intratympanic injections of saline, prednisolone, nanoparticles, or nanoparticles loaded with prednisolone. A specially designed magnet array was used to magnetically inject the particles from the middle ear to the cochlea. Treatment began at study day 0, and animals were euthanized on study day 2, 30, or 90. Temporal bones were collected and prepared for histopathological examination. Intratympanic administration of magnetic nanoparticles and/or prednisolone resulted in minimal to mild inflammatory changes in all treated groups. The incidence and severity of the inflammatory changes observed appeared slightly increased in animals administered nanoparticles, with or without prednisolone, when compared to animals administered prednisolone alone. At study day 90, there was partial reversibility of the findings noted at study day 2 and 30. Repeat administration did not appear to cause greater inflammatory changes.

Non-steroidal anti-inflammatory drugs (NSAIDs) play a significant role in the chemoprevention of cancer. We recently showed the chemopreventive response of a NSAID, 2-[(3-chloro-2-methylphenyl)amino]benzoic acid) known as tolfenamic acid (TA) in N-nitrosomethylbenzylamine (NMBA)-induced esophageal tumors in rats. Pre-clinical studies showed that TA inhibits Specificity protein (Sp) transcription factors and acts as an anti-cancer agent in several cancer models; however the pertinent mechanisms associated with its chemopreventive response in esophageal cancer are not known. Since the bioactivation of carcinogens through cytochrome P450 (CYP) is critical for the induction of cancer, we have studied the effect of TA on critical CYP isozymes in mouse liver samples. Athymic nude mice were treated with vehicle (corn oil) or TA (50 mg kg(-1), 3 times per week) for 4 weeks. Protein extracts (whole cell lysates and microsomal fractions) were prepared from liver tissue and the expression of various CYP isozymes was determined by Western blot analysis. Rat (Sprague-Dawley) livers were harvested and primary hepatocyte cultures were treated with vehicle (DMSO) or TA (50 μM) and cell viability was assessed at 2 and 5 days post-treatment. TA caused remarkable decrease in the expression of CYP2E1 in both liver lysates and sub-cellular fraction, while its response on other tested isozymes was marginal. TA did not affect the body weight of animals (mice) and viability of rat hepatocytes. These results demonstrate that TA modulates the expression of CYP2E1 which is associated with the bioactivation of carcinogens without causing apparent toxicity. These data suggest that TA-induced inhibition of CYP2E1 attenuates the bioactivation of carcinogens potentially leading to the chemoprevention of NMBA-induced esophageal tumorigenesis in rats.

Rare protein enrichment and sensitive detection hold great potential in biomedical studies and clinical practice. This work describes the use of aptamer-conjugated gold nanorods for the efficient enrichment of rare proteins from buffer solutions and human plasma. Gold nanorod (AuNR) surfaces were modified with a long PEG chain and a 15-mer thrombin aptamer for protein enrichment and detection. Studies of the effect of surface modification on enrichment efficiency of thrombin showed that a change of only one EG(6) linker unit, i.e, from 2EG(6) to 3EG(6), could increase thrombin protein capture efficiency by up to 47%. Furthermore, a 1 ppm sample of thrombin in buffer could be enriched with around 90% efficiency using a low concentration (0.19 nM) of gold nanorod probe modified with 3EG(6) spacer, and with the same probe, effective capture was achieved down to 10 ppb (1 ng) thrombin in plasma samples. In addition to alpha-thrombin enrichment, prothrombin was also efficiently captured from plasma samples via gold nanorods conjugated with 15-mer thrombin aptamer. Our work demonstrates efficient enrichment of rare proteins using aptamer-modified nanomaterials, which can be used in biomarker discovery studies.

The environment and dietary factors play an essential role in the etiology of cancer. Environmental component is implicated in ~80 % of all cancers; however, the causes for certain cancers are still unknown. The potential players associated with various cancers include chemicals, heavy metals, diet, radiation, and smoking. Lifestyle habits such as smoking and alcohol consumption, exposure to certain chemicals (e.g., polycyclic aromatic hydrocarbons, organochlorines), metals and pesticides also pose risk in causing human cancers. Several studies indicated a strong association of lung cancer with the exposure to tobacco products and asbestos. The contribution of excessive sunlight, radiation, occupational exposure (e.g., painting, coal, and certain metals) is also well established in cancer. Smoking, excessive alcohol intake, consumption of an unhealthy diet, and lack of physical activity can act as risk factors for cancer and also impact the prognosis. Even though the environmental disposition is linked to cancer, the level and duration of carcinogen-exposure and associated cellular and biochemical aspects determine the actual risk. Modulations in metabolism and DNA adduct formation are considered central mechanisms in environmental carcinogenesis. This review describes the major environmental contributors in causing cancer with an emphasis on molecular aspects associated with environmental disposition in carcinogenesis.

Magnetic relaxation switch (MRSw) detection is based on aggregate formation or dissociation when magnetic nanoparticles (MNPs) bind to target molecules. In the aggregated state, the dephasing rate of nearby proton spins is higher than in the dispersed state, resulting in a decrease in the spin-spin relaxation time, T(2). In this work, an MRSw-based nanosensor for lysozyme (Lys) protein detection was achieved using iron oxide nanoparticles conjugated with either Lys aptamer or linker DNA, which can hybridize with the extended part of the aptamer to form clusters. Upon the addition of Lys, the aptamers bind with their targets, leading to disassembly of clusters and an increase in T(2). A detection limit in the nanomolar range was achieved for Lys detection in both buffer and human serum. The determination of Lys level in different types of cancer cell lysates was also performed to demonstrate detection in real clinical samples.

In recent years, nanomaterials have captured the attention of scientists from a wide spectrum of domains. With their unique properties, nanomaterials offer great promise for numerous applications, ranging from catalysis to energy harvesting and information technology. Functionalized with the desired biomolecules, nanomaterials can also be utilized for many biomedical applications. This paper summarizes recent achievements in the use of aptamer-conjugated nanomaterials for bioanalysis and biotechnology applications. First, we discuss the features and properties of aptamers and then illustrate the use of aptamer-conjugated nanomaterials as sensing platforms and delivery vehicles, emphasizing how such integration can result in enhanced sensitivity and selectivity.

In j ngster Vergangenheit hat das Interesse f r die Entwicklung von Hybrid-Nanostrukturen, die sich aus verschiedenen Materialien zusammensetzen, in erheblichem Mase zugenommen. Es wurde berichtet, dass die Zusammenf hrung verschiedener Nanomaterialien, die ihrerseits spezifische optische, magnetische oder elektronische Eigenschaften aufweisen, zu Kompositen aus mehreren dieser Komponenten, deren individuelle Eigenschaften ver ndern oder sogar verbessern k nnen. Durch gezielte Optimierung der Struktur und der Grenzfl chenwechselwirkung innerhalb der Nanokomposite k nnte eine breite Basis f r zuk nftige Technologien geschaffen werden, beispielweise f r die synchrone Biomarkierung, Proteintrennung und -detektion, heterogene Katalyse und multimodale biomedizinische Bildgebung. Unter den verschiedenen Arten von Nanomaterialien spielen Goldnanost be wegen ihrer ausergew hnlich hohen Polarisierbarkeit im optischen Frequenzbereich, die von der Anregung lokalisierter Oberfl chenplasmonenresonanzen herr hrt, eine besondere Rolle. Zus tzlich weisen Goldnanost be vielversprechende therapeutische Eigenschaften als Hyperthermie-Wirkstoffe auf, da die Temperatur um die Nanost be rtlich durch die gezielte Anregung der Oberfl chenplasmonen nach Bestrahlung mit Infrarotlasern erh ht werden kann. Die Verwendung von Nahinfrarot-Strahlung bietet dar ber hinaus den Vorteil einer geringen Absorption und Streuung durch Blut und umgebendes Gewebe, was ein tieferes Eindringen der Strahlung in den K rper erm glicht. Magnetische Nanopartikel stellen eine weitere Klasse von Nanomaterialien dar, die in den vergangenen Jahren erhebliches Forschungsinteresse geweckt hat. Vor allem austauschgekoppelte magnetische Nanokomposite wie antiferromagnetische/ferromagnetische Kern-Schale-Nanopartikel (z.B. MnO/Mn3O4) weisen magnetische Eigenschaften auf, die sich von denen der einzelnen Komponenten stark unterscheiden. Im Bezug auf biomedizinische Anwendungen ist seit einigen Jahren bekannt, dass sich superparamagnetische Nanopartikel als Kontrastmittel f r die Magnetresonanztomographie (MRT) nutzen lassen. Die meisten Nanopartikel, die in diesem Kontext untersucht wurden, enthalten unterschiedliche Eisenoxide (Fe3O4, g-Fe2O3), welche die transversale (oder Spin-Spin-) Relaxationszeit T2 verk rzen. [11] Vor kurzem konnte dar ber hinaus gezeigt werden, dass Manganoxid(MnO)-Nanopartikel zu einer Verk rzung der longitudinalen (oder Spin-Gitter-) Relaxationszeit T1 f hren. Daher w re ein Nanopartikelsystem, das sowohl eine optisch adressierbare Au-Einheit als auch eine magnetisch aktive MnO-Komponente enth lt, f r eine simultane optische und MRT-Detektion besonders vorteilhaft. Obwohl in j ngster Zeit die Entwicklung geeigneter Oberfl chenliganden stark vorangetrieben wurde, ist die spezifische Adressierbarkeit der Oberfl che f r biologische Anwendungen noch immer ein groses Hindernis. Daher bietet ein Nanokomposit mit individuell ansprechbaren Auund MnO-Dom nen zwei verschiedene Oberfl chen f r die selektive Anbindung unterschiedlicher Molek le, was das Potenzial f r Diagnostik und Therapie wesentlich erh ht. Auserdem kann die Gr se der jeweiligen Komponente zur Optimierung der optischen und magnetischen Eigenschaften variiert werden. Hier berichten wir ber die Synthese von Au@MnO-Nanokompositen, die aus superparamagnetischen MnO-Nanopartikeln und Au-Kristalliten bestehen, sowie [*] T. D. Schladt, Dr. M. I. Shukoor, K. Schneider, Dr. M. N. Tahir, O. K hler, Prof. Dr. W. Tremel Institut f r Anorganische Chemie und Analytische Chemie Johannes Gutenberg-Universit t Duesbergweg 10-14, 55099 Mainz (Deutschland) Fax: (+49)6131-39-25605 E-Mail : tremel@uni-mainz.de

Here, design of the first pathogen-mimicking metal oxide nanoparticles with the ability to enter cancer cells and to selectively target and activate the TLR9 pathway, and with optical and MR imaging capabilities, is reported. The immobilization of ssDNA (CpG ODN 2006) on MnO nanoparticles is performed via the phosphoramidite route using a multifunctional polymer. The multifunctional polymer used for the nanoparticle surface modification not only affords a protective organic biocompatible shell but also provides an efficient and convenient means for loading immunostimulatory oligonucleotides. Since fluorescent molecules are amenable to photodetection, a chromophore (Rhodamine) is introduced into the polymer chain to trace the nanoparticles in Caki-1 (human kidney cancer) cells. The ssDNA coupled nanoparticles are used to target Toll-like receptors 9 (TLR9) receptors inside the cells and to activate the classical TLR cascade. The presence of TLR9 is demonstrated independently in the Caki-1 cell line by western blotting and immunostaining techniques. The magnetic properties of the MnO core make functionalized MnO nanoparticles potential diagnostic agents for magnetic resonance imaging (MRI) thereby enabling multimodal detection by a combination of MR and optical imaging methods. The trimodal nanoparticles allow the imaging of cellular trafficking by different means and simultaneously are an effective drug carrier system.

Multifunctional polymer-derivatized superparamagnetic iron oxide (γ-Fe2O3) nanoparticles were prepared for biomagnetic separation of histidine-tagged recombinant proteins building up a faster and efficient method for protein separation by making use of their intrinsic magnetic properties. Using polymer bound γ-Fe2O3 nanocrystals, a 6× histidine-tagged recombinant protein (silicatein) with a molecular weight of 24 kDa has been isolated and purified. The supermagnetic iron oxide nanocrystals were characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), SQUID and Mossbauer and the polymer functionalization of the γ-Fe2O3 nanocrystals was monitored by UV–vis spectroscopy and light microscopy. Protein immobilization and separation was monitored using immunostaining techniques and gel electrophoresis, respectively.

Silicatein, a hydrolytic protein encountered in marine sponges, was immobilized on maghemite (γ-Fe2O3) nanoparticles that were surface functionalized with a reactive mulfunctional polymer. This polymer carries an anchor group based on dopamine which is capable of binding to the γ-Fe2O3 surface and a reactive functional group which allows binding of various biomolecules onto inorganic nanoparticles. This functional nitrilotriacetic acid (NTA) group allows immobilization of His-tagged silicatein on the surface of the γ-Fe2O3 nanoparticles. The surface-bound protein retains its native hydrolytic activity to catalyze formation of silica through copolymerization of alkoxysilanes Si(OR)4. Functionalization of the magnetic nanoparticles and the architecture of the SiO2-coated γ-Fe2O3 nanoparticles was confirmed by TEM studies as well as by FT-IR and optical microscopy.

Aquatic animals, especially filter feeders such as sponges [phylum Porifera], are exposed to a higher viral load than terrestrial species. Until now, the antiviral defense system in the evolutionary oldest multicellular organisms, sponges, is not understood. One powerful protection of vertebrates against virus infection is mediated by the interferon (IFN)-inducible 2'-5'-oligoadenylate synthetase [(2-5)A synthetase] system. In the present study we cloned from the freshwater sponge Lubomirskia baicalensis a cDNA encoding a 314 aa long ORF with a calculated size of 35748Da, a putative (2-5)A synthetase, and raised antibodies against the recombinant protein. The native enzyme was identified in a crude extract from L. baicalensis by application of a novel separation procedure based on polymer coated ferromagnetic nanoparticles. The particles were derivatized with a synthetic double-stranded RNA [dsRNA], synthetic poly(I:C), a known allosteric activator of the latent (2-5)A synthetase. These particles were used to separate a single 35kDa protein from a crude extract of L. baicalensis, which cross-reacted with antibodies raised against the sponge enzyme. In situ hybridization studies revealed that highest expression of the gene is seen in cells surrounding the aquiferous canals. Finally primmorphs, an in vitro cell culture system, from L. baicalensis were exposed to poly(I:C); they responded to this dsRNA with an increased expression of the (2-5)A synthetase gene already after a 1-day incubation period. We conclude that sponges contain the (2-5)A synthetase antiviral protection system.

Nanostructures of varied dimensionality such as rods, scrolls, and disks of molybdenum oxide have been synthesized in gram quantities under ambient conditions using exfoliation of the layers as a synthetic tool. Intercalation of alkylamines (CnH2n+2NH2, where n = 3, 4, 8, 12, and 16) into yellow molybdic acid (MoO3·2H2O) and subsequent treatment with nitric acid resulted in molybdenum oxide nanorods, nanodisks, or oxide−amine composite nanorods. The sizes of the nanoparticles range from a few nanometers to micrometers in length and 10 to 200 nm in diameter. Detailed X-ray, scanning electron microscopy, and transmission electron microscopy analyses reveal an inverse relation between the size of the nanoparticles and the chain length of the guest molecules. Infrared and thermogravimetric studies throw light on the driving force for the amine intercalation and the orientation of the intercalated amine molecules.

Although many different nanomaterials have been tested as substrates for laser desorption and ionization mass spectrometry (LDI-MS), this emerging field still requires more efficient multifuncional nanomaterials for targeting, enrichment and detection. Here, we report the use of gold-manganese oxide (Au@MnO) hybrid nanoflowers as an efficient matrix for LDI–MS. The nanoflowers were also functionalized with two different aptamers to target cancer cells and capture adenosine triphosphate (ATP), respectively. These nanoflowers were successfully used for metabolite extraction from cancer cell lysates. Thus, in one system, our multifunctional nanoflowers can 1) act as an ionization substrate for mass spectrometry, 2) target cancer cells, and 3) detect and analyze metabolites from cancer cells.

In this work, a DNA inter-strand replacement strategy for therapeutic activity has been successfully designed for multimodal therapy. In this multimodal therapy, chlorin e6 (Ce6) photosensitizer molecules are used for photodynamic therapy (PDT), while aptamer-AuNRs, are used for selective binding to target cancer cells and for photothermal therapy (PTT) with near infrared (NIR) laser irradiation. Aptamer Sgc8, which specifically targets leukemia T cells, is conjugated to an AuNR by a thiol-Au covalent bond. and then hybridized with a Ce6-labeled photosensitizer/reporter to form a DNA double helix. When target cancer cells are absent, Ce6 is quenched and shows no PDT effect. However, when target cancer cells are present, the aptamer changes structure to release Ce6 to produce singlet oxygen for PDT upon light irradiation. Importantly, by combining photosensitizer and photothermal agents, PTT/PDT dual therapy supplies a more effective therapeutic outcome than either therapeutic modality alone.

In this work, gold nanoparticles perform Boolean logic operations in response to two proangiogenic targets important in cancer diagnosis and treatment: PDGF and VEGF. In the absence of protein target, gold nanoparticles are initially dispersed as a red solution; the addition of target proteins causes nanoparticle aggregation, turning the solution blue, as well as the release of dye-labeled aptamer probes, which causes an increase in fluorescence. These outputs constitute an AND or OR gate for simultaneous protein detection. We believe this logic-gate-based detection system will become the basis for novel rapid, cheap, and reliable sensors for diagnostic applications.

Biocompatible magnetic nanosensors based on reversible self-assembly of dispersed magnetic nanoparticles into stable nanoassemblies have been used as effective magnetic relaxation switches (MRSw) for the detection of molecular interactions. We report, for the first time, the design of MRSw based on aptamer-conjugated magnetic nanoparticles (ACMNPs). The ACMNPs capitalize on the ability of aptamers to specifically bind target cancer cells, as well as the large surface area of MNPs to accommodate multiple aptamer binding events. The ACMNPs can detect as few as 10 cancer cells in 250 μL of sample. The ACMNPs’ specificity and sensitivity are also demonstrated by detection in cell mixtures and complex biological media, including fetal bovine serum (FBS), human plasma, and whole blood. Furthermore, by using an array of ACMNPs, various cell types can be differentiated through pattern recognition, thus creating a cellular molecular profile which will allow clinicians to accurately identify cancer cells at the molecular and single cell level.

Smart multifunctional magnetic nanoparticles are popular candidates for several biological applications owing to their intrinsic magnetic property and diverse applications that range from rare protein separation and biomedical utilization to cancer therapy and diagnostics. A universal protocol, for the development of such nanocarriers, is highly desirable for scientists with different backgrounds so that custom-made multifunctional nanoparticles can be developed to address their needs, among which are the superparamagnetic iron oxide and manganese oxide nanoparticles that are synthesized through high temperature decomposition reactions. However, an interface is needed to present these inorganic materials to biomolecules to enhance their application for different biological use. This compatibility is achieved by introducing a class of multifunctional copolymers. Magnetic nanoparticles are elaborately decorated with copolymers that carry three principle functionalities as follows: (1) dopamine moieties for surface anchorage of metal oxides; (2) dyes for optical detection; and (3) a large variety of functional molecules such as amines or carboxylates for conjugation of various biomolecules (i.e., proteins, nucleic acids, enzymes, etc.). These copolymers, in combination with nanoparticles, serve as a tool box that results in engineered nanotools with customized modifications and functionalities for applications in fields ranging from proteomics -bioseparation to tumor therapy.

Targeted chemotherapy and magnetic resonance imaging of cancer cells in vitro has been achieved using a smart multifunctional nanostructure (SMN) constructed from a porous hollow magnetite nanoparticle (PHMNP), a heterobifunctional PEG ligand, and an aptamer. The PHMNPs were prepared through a three-step reaction and loaded with the anticancer drug doxorubicin while being functionalized with PEG ligands. Targeting aptamers were then introduced by reaction with the PEG ligands. The pores of the PHMNPs are stable at physiological pH, but they are subject to acid etching. Specific binding and uptake of the SMN to the target cancer cells induced by aptamers was observed. In addition, multiple aptamers on the surface of one single SMN led to enhanced binding and uptake to target cancer cells due to the multivalent effect. Upon reaching the lysosomes of target cancer cells through receptor-mediated endocytosis, the relatively low lysosomal pH level resulted in corrosion of the PHMNP pores, facilitating the release of doxorubicin to kill the target cancer cells. In addition, the potential of using SMN for magnetic resonance imaging was also investigated.

Smart multifunctional magnetic nanoparticles are popular candidates for several biological applications owing to their intrinsic magnetic property and diverse applications that range from rare protein separation and biomedical utilization to cancer therapy and diagnostics. A universal protocol, for the development of such nanocarriers, is highly desirable for scientists with different backgrounds so that custom-made multifunctional nanoparticles can be developed to address their needs, among which are the superparamagnetic iron oxide and manganese oxide nanoparticles that are synthesized through high temperature decomposition reactions. However, an interface is needed to present these inorganic materials to biomolecules to enhance their application for different biological use. This compatibility is achieved by introducing a class of multifunctional copolymers. Magnetic nanoparticles are elaborately decorated with copolymers that carry three principle functionalities as follows: (1) dopamine moieties for surface anchorage of metal oxides; (2) dyes for optical detection; and (3) a large variety of functional molecules such as amines or carboxylates for conjugation of various biomolecules (i.e., proteins, nucleic acids, enzymes, etc.). These copolymers, in combination with nanoparticles, serve as a tool box that results in engineered nanotools with customized modifications and functionalities for applications in fields ranging from proteomics -bioseparation to tumor therapy.

Recently, the development of hybrid nanostructures consisting of various materials has attracted considerable interest. The assembly of different nanomaterials with specific optical, magnetic, or electronic properties to multicomponent composites can change and even enhance the properties of the individual constituents. Specifically tuning the structure and interface interactions within the nanocomposites has resulted in novel platforms of materials that may lead the way to various future technologies, such as synchronous biolabeling, protein separation and detection, heterogeneous catalysis, and multimodal imaging in biomedicine. Of the various kinds of nanomaterials, gold nanorods show an unusually high polarizability at optical frequencies arising from the excitation of localized surface-plasmon resonances (LSPRs). Furthermore, gold nanorods have promising therapeutic properties as hyperthermal agents because the local temperature around the gold nanorods can be increased by laser illumination through the tunable surface plasmon bands in the near infrared (NIR) region. Using NIR radiation for hyperthermal therapy is beneficial because of the low absorption and low scattering by blood and tissue in this spectral range. Magnetic nanoparticles constitute another major class of nanomaterials that have attracted much research effort over the past decades. In particular, exchange-coupled magnetic nanocomposites, such as antiferromagnetic/ferromagnetic core–shell nanoparticles, such as MnO/Mn3O4, have magnetic properties that are quite different from those of the individual components. Concerning biomedical applications, superparamagnetic nanoparticles are attractive as contrast agents for magnetic resonance imaging (MRI). The majority of nanoparticles that have been investigated in this field comprise iron oxides (Fe3O4, g-Fe2O3), which are known to shorten the transverse (or spin–spin) relaxation time T2. [11] Recently, manganese oxide nanoparticles (MnO NPs) have been shown to be interesting candidates as contrast agents for shortening of the longitudinal (or spin-lattice) relaxation time T1. [12] Consequently, a nanoparticulate system containing both an optically active plasmonic gold unit and a magnetically active MnO component would be advantageous for simultaneous optical and MRI detection. Although considerable research efforts have been put into the chemical design of suitable surface ligands, one of the major obstacles for biocompatible applications remains the lack of surface addressability. Therefore, a nanocomposite made up of individually addressable Au and MnO domains offers two functional surfaces for the attachment of different kinds of molecules, thus increasing both diagnostic and therapeutic potential. Furthermore, the size of either of the two components can be varied to optimize the magnetic and optical properties. Herein we present the successful synthesis of Au@MnO nanocomposites consisting of both paramagnetic MnO NPs and Au crystallites followed by separate surface functionalization of both domains with fluorescent ligands. Scheme 1 depicts a functionalized Au@MnO nanoflower with selective attachment of catechol anchors to the metal oxide petals and thiol anchors to the gold core. The nanoflowers were synthesized by decomposition of manganese acetylacetonate [Mn(acac)2] in diphenyl ether in the presence of preformed Au NPs (“seeds”), with oleic acid and oleylamine as surfactants, following a similar procedure for the preparation of Au@Fe3O4 heteroparticles by Sun et al. [15] The [*] T. D. Schladt, Dr. M. I. Shukoor, K. Schneider, Dr. M. N. Tahir, O. K hler, Prof. Dr. W. Tremel Institut f r Anorganische Chemie und Analytische Chemie Johannes-Gutenberg-Universit t Duesbergweg 10–14, 55099 Mainz (Germany) Fax: (+49)6131-39-25605 E-mail: tremel@uni-mainz.de

The immobilization of polyinosinic-polycytidylic acid [poly(IC)] on ã-Fe2O3 maghemite nanoparticles via the phosphor-amidate route using a multifunctional polymer is reported. The dsRNA coupled nanoparticles were used to visualize the Toll-like (TLR3) receptors at the cell surface. The presence of TLR3 was demonstrated independently in the Caki-1 cell line by RT-PCR and immunostaining techniques

Ovarian cancer (OC) is one of the most common female cancers and is the leading cause of death from gynecologic malignancies. Although, cisplatin is the front-line chemotherapeutic option for OC, its success is compromised due to dose-limiting toxicity and acquired resistance by tumor cells. Specificity protein 1 (Sp1) is a transcription factor that is over-expressed in several cancers and is inversely associated with survival. Survivin, a member of IAP family, is known to cause resistance to chemo- and radiation therapy. Studies from our laboratories have shown that the NSAID, tolfenamic acid (TA), targets Sp1 protein and inhibits expression of survivin in various cancer models. Our primary objective was to evaluate the expression of Sp1 and survivin in OC patients’ specimens and target these candidates using TA for enhancing the cisplatin response. Expression of Sp1 and survivin in clinical specimens was determined by qPCR and Western blots. qPCR showed increased expression of survivin (∼5-fold) and Sp1 (∼2-fold) in tumor samples. Western blot also revealed over-expression of both Sp1 (>2.6-fold) and survivin (>100-fold). OC cell lines (ES2, OVCAR-3) were used to determine the anti-proliferative response to cisplatin and TA. TA and cisplatin showed a dose- and time-dependent inhibition of cell viability in OC cell lines [TA (50 ÂμM) caused 50% (ES2) and 40% (OVCAR-3) growth inhibition and cisplatin (5 ÂμM) caused 60% and 40% inhibition at 48 h post-treatment]. Combination treatment using optimized doses of TA (50 ÂμM) and cisplatin (5 ÂμM) resulted in a synergistic response and caused stronger inhibition (ES2: ∼80%, OVCAR-3: >60) compared to single-agent. Increased inhibition of proliferation by the combination of TA and cisplatin was accompanied by cell-cycle arrest, predominantly in the G2/M phase. A significant increase in apoptosis, as determined by Caspase 3/7 activity, annexin-V staining, and PARP cleavage, was also observed in the combination treatment. Cell invasion and migration was assessed using matrigel coated transwell chambers. Compared to TA or cisplatin treatment alone, their combination significantly inhibited ES2 cell invasion. Analysis of ES2 cells by global proteomic profiling indicated that the combination treatment upregulated proteins associated with oxidative phosphorylation, apoptosis, and electron transport chain; and down-regulated cytoplasmic ribosomal proteins, translational factors, and proteins involved in DNA damage response, and cell cycle. In conclusion, elevated expression of Sp1 and survivin confirmed their association in OC and demonstrated the relevance of targeting these candidates, which may render the OC cells more sensitive to chemotherapy and offer therapeutic potential. Further studies to delineate underlying mechanism(s) of action possibly involving signaling pathways and reactive oxygen species are currently underway. Citation Format: Umesh T. Sankpal, Susan B. Ingersoll, Mohammed I. Shukoor, Chris M. Lee, Nicole M. Stavitzski, Vadiraja B. Bhat, Sarfraz Ahmad, Robert W. Holloway, Liz Abraham, Riyaz Basha. Expression of Sp1 and survivin in ovarian cancer specimens: potential novel therapeutic targets in disease treatment. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2159. doi:10.1158/1538-7445.AM2013-2159

Initiation of pathways that lead to a proliferation and chemoresistance by Toll-like receptors (TLRs) are an important factor in cancer progression. Multifunctional magnetic nanoparticles equipped with a pathogen-derived ligand (CpG) functioning as TLR agonists were used to show the impact of immune activation on human HNSCC (head and neck squamous cell carcinoma) cells. The response of human cancer cells to TLR signaling is linked to tumor biology. The magnetic MnO nanoparticles were coated with a multifunctional polymer, displaying no cytotoxicity and being able to enter cells while carrying foreign DNA (unmethylated CpG) to recognize intracellular TLR9. Both the particle and the nucleic acid were tagged with fluorescent markers for simultaneous visualization inside the cell. Cell and animal studies show that the multimodal nanoparticles used as a TLR carrier system allow monitoring simultaneously nanoparticle cellular trafficking and transport by optical and MRI imaging.

Polymer coated superparamagnetic gamma-Fe(2)O(3) nanoparticles were derivatized with a synthetic double-stranded RNA [poly(IC)], a known allosteric activator of the latent (2-5)A synthetase, to separate a single 35 kDa protein from a crude extract which cross reacted with antibodies raised against the sponge enzyme.

Initiation of pathways that lead to proliferation and chemoresistance by Toll-like receptors (TLRs) is an important factor in cancer progression. Here, we show the response of human cancer cells to TLR signaling inevitably linked to tumor biology. The approach is based on tailored multifunctional magnetic nanoparticles equipped with pathogen-derived ligands (CpG) functioning as TLR agonists (molecular component) to investigate the impact of transcription factor immune activation on human cancer cells. Magnetic nanoparticles (MnO and bifunctional Au-MnO) particles were covalently coated with a multifunctional polymer, displaying no cytotoxicity, to being able to enter cells while carrying foreign DNA (unmethylated CpG) to recognize intracellular TLR 9. Both, the particle and the nucleic acid are tagged with fluorescent markers for simultaneous visualization inside the cell. Apart from optical imaging, the magnetism of the particles also allows magnetic resonance imaging of organisms.

MnO nanoparticles were conjugated to single stranded DNA (ssDNA), Cytosin-phosphatidyl-Guanosin oligonucleotide (CpG ODN) to detect and activate Toll-like (TLR9) receptors in cells and to follow nanoparticle cellular trafficking by different means of imaging while at the same time serving as a drug carrier system. By virtue of their magnetic properties these nanoparticles may serve as vehicles for the transport of target molecules into cells, while the fluorescent target ligand allows optical detection simultaneously.x