Magnetic aerosol targeting of nanoparticles to cancer: nanomagnetosols

Preparation and Characterization of Magnetic Nano-in-Microparticles for Pulmonary Delivery

The purpose of this chapter is to detail the formulation and characterization of a magnetically-targeted drug delivery vehicle, termed nano-in-microparticles (NIMs), for pulmonary drug delivery. Currently, chemotherapeutics and antibiotics are delivered systemically and result in whole body side-effects. NIMs are formulated with superparamagnetic iron oxide nanoparticles, termed SPIONs, making these particles targetable to specific lung regions using a strong external magnet. Additionally, these particles can be formulated to contain any drug or therapeutic agent, such that a therapeutic dose can be delivered to a specific tissue location using the SPIONs-magnet interaction. Finally, these particles are in the appropriate size range for pulmonary delivery, making NIMs therapeutics feasibly inhalable.To generate these particles a solution containing lactose, SPIONs, and a microsphere dye (used as a drug surrogate) is spray-dried using a laboratory-scale spray dryer. The resulting dry powder microparticles (NIMs) can be characterized for their size and morphological properties by various techniques that are presented in this chapter.The utility of NIMs as a magnetic field-dependent targeting delivery platform in an in vivo mouse model has been demonstrated, and a protocol detailing the intratracheal delivery of NIMs dry powder is included as a separate chapter in this book.

Recent advances in the preparation and application of multifunctional iron oxide and liposome-based nanosystems for multimodal diagnosis and therapy

Nowadays, thanks to the successful discoveries in the biomedical field achieved in the last two decades, a deeper understanding about the complexity of mechanistic aspects of different pathological processes has been obtained. As a consequence, even the standard therapeutic protocols have undergone a vast redesign. In fact, the awareness about the necessity to progress towards a combined multitherapy in order to potentially increase the final healing chances has become a reality. One of the crucial elements of this novel approach is that large amounts of detailed information are highly needed and in vivo imaging techniques represent one of the most powerful tools to visualize and monitor the pathological state of the patient. To this scope, due to their unique features, nanostructured materials have emerged as attractive elements for the development of multifunctional tools for diagnosis and therapy. Hence, in this review, the most recent and relevant advances achieved by applying multifunctional nanostructures in multimodal theranosis of different diseases will be discussed. In more detail, the preparation and application of single multifunctional nano-radiotracers based on iron oxides and enabling PET/MRI dual imaging will be firstly detailed. After that, especially considering their highly promising clinical potential, the preparation and application of multifunctional liposomes useful for multimodal imaging and therapy will be reviewed. In both cases, a special focus will be set on the application of such a multifunctional nanocarriers in cancer as well as cardiovascular diseases.

Emerging aerosol drug delivery strategies: from bench to clinic

Patients with tracheostomies, those requiring mechanical ventilation, and those too small or compromised for conventional devices, are realizing the benefits of increasingly sophisticated aerosol delivery systems. New medicines and novel aerosol formulations, have enhanced our ability to treat lung disease, and are opening the doors for therapy to treat diseases like diabetes, pulmonary hypertension, and cancer. Progress in the aerosol delivery of drugs has been spurred by the significant benefits, including ease of use, patient comfort, greater selectivity of effect, and the potential to decrease side effects.

Superparamagnetic iron oxide nanoparticles (SPIONs)-loaded Trojan microparticles for targeted aerosol delivery to the lung

Targeted aerosol delivery to specific regions of the lung may improve therapeutic efficiency and minimise unwanted side effects. Targeted delivery could potentially be achieved with porous microparticles loaded with superparamagnetic iron oxide nanoparticles (SPIONs)-in combination with a target-directed magnetic gradient field. The aim of this study was to formulate and evaluate the aerodynamic properties of SPIONs-loaded Trojan microparticles after delivery from a dry powder inhaler. Microparticles made of SPIONs, PEG and hydroxypropyl-β-cyclodextrin (HPβCD) were formulated by spray drying and characterised by various physicochemical methods. Aerodynamic properties were evaluated using a next generation cascade impactor (NGI), with or without a magnet positioned at stage 2. Mixing appropriate proportions of SPIONs, PEG and HPβCD allowed Trojan microparticle to be formulated. These particles had a median geometric diameter of 2.8±0.3μm and were shown to be sensitive to the magnetic field induced by a magnet having a maximum energy product of 413.8kJ/m(3). However, these particles, characterised by a mass median aerodynamic diameter (MMAD) of 10.2±2.0μm, were considered to be not inhalable. The poor aerodynamic properties resulted from aggregation of the particles. The addition of (NH4)2CO3 and magnesium stearate (MgST) to the formulation improved the aerodynamic properties of the Trojan particles and resulted in a MMAD of 2.2±0.8μm. In the presence of a magnetic field on stage 2 of the NGI, the amount of particles deposited at this stage increased 4-fold from 4.8±0.7% to 19.5±3.3%. These Trojan particles appeared highly sensitive to the magnetic field and their deposition on most of the stages of the NGI was changed in the presence compared to the absence of the magnet. If loaded with a pharmaceutical active ingredient, these particles may be useful for treating localised lung disease such as cancer nodules or bacterial infectious foci.

Preparation and characterization of novel magnetic nano-in-microparticles for site-specific pulmonary drug delivery

We propose the use of novel inhalable nano-in-microparticles (NIMs) for site-specific pulmonary drug delivery. Conventional lung cancer therapy has failed to achieve therapeutic drug concentrations at tumor sites without causing adverse effects in healthy tissue. To increase targeted drug delivery near lung tumors, we have prepared and characterized a magnetically responsive dry powder vehicle containing doxorubicin. A suspension of lactose, doxorubicin and Fe3O4 superparamagnetic iron oxide nanoparticles (SPIONs) were spray dried. NIMs were characterized for their size and morphological properties by various techniques: dynamic light scattering (DLS) and laser diffraction (LS) to determine hydrodynamic size of the SPIONs and the NIMs, respectively; next generation cascade impactor (NGI) to determine the aerodynamic diameter and fine particle fraction (FPF); scanning (SEM) and transmission (TEM) electron microscopy to analyze particle surface morphology; electron dispersive X-ray spectroscopy (EDS) to determine iron loading in NIMs; inductively coupled plasma atomic emission spectroscopy (ICP-AES) and superconducting quantum interference device (SQUID) to determine Fe3O4 content in the microparticles; and high performance liquid chromatography (HPLC) to determine doxorubicin loading in the vehicle. NIMs deposition and retention near a magnetic field was performed using a proof-of-concept cylindrical tube to mimic the conducting airway deposition. The hydrodynamic size and zeta potential of SPIONs were 56 nm and -49 mV, respectively. The hydrodynamic and aerodynamic NIM diameters were 1.6 μm and 3.27±1.69 μm, respectively. SEM micrographs reveal spherical particles with rough surface morphology. TEM and focused ion beam-SEM micrographs corroborate the porous nature of NIMs, and surface localization of SPIONs. An in vitro tracheal mimic study demonstrates more than twice the spatial deposition and retention of NIMs, compared to a liquid suspension, in regions under the influence of a strong magnetic gradient. We report the novel formulation of an inhaled and magnetically responsive NIM drug delivery vehicle. This vehicle is capable of being loaded with one or more chemotherapeutic agents, with future translational ability to be targeted to lung tumors using an external magnetic field.

Peptide nanomedicines for treatment of acute lung injury

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) represent a heterogenous group of lung disease in critically ill patients. Despite the increased understanding of the molecular pathogenesis of ARDS, the mortality remains unacceptably high, ranging from 34% to 64%. Hence, ARDS represents an unmet medical need with an urgency to develop effective pharmacotherapies. Several promising targets that have been identified as potential therapies for ARDS have been limited because of difficulty with delivery. In particular, delivery of peptides and proteins to the lung is an ongoing challenge. Nanobiotechnology and nanoscience are the basis of innovative techniques to deliver drugs targeted to the site of inflamed organs, such as the lungs. Nanoscale drug delivery systems have the ability to improve the pharmacokinetics and pharmakodynamics of agents allowing an increase in the biodistribution of therapeutic agents to target organs, resulting in improved efficacy with reduction in drug toxicity. These systems are exploited for therapeutic purpose to carry the drug in the body in a controlled manner from the site of administration to the therapeutic target. Hence, it is an attractive strategy to test potential targets for ALI/ARDS using nanotechnology. To this end, we have identified several potential targets and proposed the delivery of these agents using nanomicelles to improve the drug delivery.

Nanoparticle-mediated signaling endosome localization regulates growth cone motility and neurite growth

Understanding neurite growth regulation remains a seminal problem in neurobiology. During development and regeneration, neurite growth is modulated by neurotrophin-activated signaling endosomes that transmit regulatory signals between soma and growth cones. After injury, delivering neurotrophic therapeutics to injured neurons is limited by our understanding of how signaling endosome localization in the growth cone affects neurite growth. Nanobiotechnology is providing new tools to answer previously inaccessible questions. Here, we show superparamagnetic nanoparticles (MNPs) functionalized with TrkB agonist antibodies are endocytosed into signaling endosomes by primary neurons that activate TrkB-dependent signaling, gene expression and promote neurite growth. These MNP signaling endosomes are trafficked into nascent and existing neurites and transported between somas and growth cones in vitro and in vivo. Manipulating MNP-signaling endosomes by a focal magnetic field alters growth cone motility and halts neurite growth in both peripheral and central nervous system neurons, demonstrating signaling endosome localization in the growth cone regulates motility and neurite growth. These data suggest functionalized MNPs may be used as a platform to study subcellular organelle localization and to deliver nanotherapeutics to treat injury or disease in the central nervous system.