Magnetic nanoparticles have proven particularly effective in chemotherapeutics applications. By combining the physical and chemical properties of more than one component material, nanoparticles can be designed that contain multiple functionalities, thereby dramatically increasing therapeutic efficacy. Recently, a research group out of University College Dublin in Ireland developed nanoparticles with distinct outer segments. The researchers coupled the properties of each of the segments to yield particles capable of performing diagnostic and therapeutic operations, inducing targeted cell death through multiple mechanisms.
Nitrite and nitrate pollutants in soil and water pose significant health risks. The presence of these pollutants in drinking water can have serious consequences, including cancer, methemoglobinemia, and blue baby syndrome in newborns. Removal of these contaminants is essential to the maintenance of environmental and human health. Developing efficient strategies for removal, however, has proved challenging.
An article by Sepmag founder and CSO, Dr. Lluis M. Martinez, appears online this week in Genetic Engineering & Biotechnology News. The article addresses issues thatariseduring a biomagnetic separation application and offers critical suggestions for approaching a process. Of particular importance is an understanding of the inherent parameters of a separation.
Mechanical stimulation is an important aspect of bone metabolism and regeneration. A number of studies have highlighted the importance of mechanotransduction pathways in osteogenic mesenchymal stem cell (MSC) differentiation.Providing a mechanical stimulus can have a significant role in the outcome of regenerative treatments.
Applying a mechanical load to damaged bone, however, is not always feasible. A recent study published in “Stem Cells Translational Medicine”describes a novel procedure forsuch cases. The protocol makes use of superparamagnetic nanoparticles to remotely induce mechanotransduction.
Using magnetic nanoparticles to activate mechanotransduction pathways
By targeting magnetic nanoparticles to cell-surface mechanosensors, researchers sought to deliver a stimulus to directly activate mechanotransduction pathways. Magnetic nanoparticles were labeled with either Arg-Gly-Asp (RGD) tripeptide or TREK1-Ab, targeting particles to mechanically gated receptors, i.e., integrin RGD-binding domains and TREK1 stretch-activated ion channels, respectively.
An oscillating magnetic field was applied, yielding a force of 4 pN per nanoparticle. Bound nanoparticles transferred the force generated by the external magnetic field to the stem cells via the receptors or ion channels to which they were attached, thus inducing mechanotransduction pathways. The result was propagation of the stimulus without the associated application of mechanical stress.
Stimulating bone growth
Researchers demonstratedthe principles oftheir technique in vitro utilizing chicken fetal femurs and collagen hydrogels. MSCs labeled with magnetic nanoparticles were delivered to the femur by microinjection. MSCs receiving mechanical stimuli via bound nanoparticles showed increased bone formation in comparison withunlabeled MSCs. Similarly, collagen hydrogels seeded with nanoparticle-labeled cells displayed increases in both volume and density, and significantly more mineralization than hydrogels seeded with unlabeled cells.
Combining mechanotransduction with the sustained release of bone morphogenetic protein 2 (BMP2) delivered by bioresorbable polymer microparticles resulted in an even greater increase in bone formation than that observed with either nanoparticle-mediated mechanotransduction or BMP2 alone. The microparticles, measuring 10–40 μm in diameter, were engineered to release BMP2 in controlled bursts over a number of days.The resulting synergistic effect underlines the potential for the procedure when combined with existing pharmacological therapies and other strategies for bone regeneration.
Researchers point out the range of possible MSC targets, both intra and extracellular, and thepotential for controlling the applied stimulus by altering the magnetic field strength or the number and size of the magnetic particles. Future avenues of study will include investigating the result of stimulating additional mechanoreceptors, either alone or in combination with the sustained release of growth factors.
A full report of the study can be accessed online in the Stem Cells Translational Medicine site.
Related news:
- New Sepmag (free) eBooks page
- Using Magnetic Nanoparticles to Localize Heat-Inducible Gene Expression
- Where to see SEPMAG at MEDICA 2014?
MEDICA is here! Unfortunately, we will not be able to attend this year as our senior technical-sales team is engaged with large projects overseas this quarter (Bryan in North America and Lluis in Japan). But don’t worry!If you want to see SEPMAG, our advanced biomagnetic systems will be available at different stands, displayed by manufacturers who will be utilizing it to demonstrate the performance of their magnetic beads.
A recent study published in “ACS Synthetic Biology” utilizes magnetic nanoparticles to facilitate gene therapy in tumor cells. The approach combines two effective cancer treatments – hyperthermia and gene therapy – to develop a remotely controlled magnetic switch capable of inducing gene expression. The result is significantly inhibited tumor growth in vivo.
As part of their effort to disseminate knowledge on biomagnetic separation, SEPMAG publishes eBooks and documents about the subject. Prepared by internal and external experts, these materials are available for free to the scientific and industrial Life Science community.
Earlier last week, Google revealed details regarding its most recent biomedical technology project: magnetic nanoparticles capable of providing advanced warning of impending disease. The announcement was made by Andrew Conrad, a member of Google’s special projects division, Google X. Conrad, who heads Google X’s Life Science team, reported that the company is developing nanoparticles capable of monitoring an individual for early signs of impairment, such as cancer, heart attack, and stroke.
Biomolecules circulating within an organism can be likened to a data stream, providing valuable information that can be accessed to identify disease states and processes such as inflammation. Recent studies have focused on developing autonomous devices for this purpose, incorporating biologically derived molecules such as DNA into computing structures capable of analyzing biomolecular input and carrying out logic-gated functions such as cellular analysis and molecule delivery. Magnetic nanoparticles possess inherent properties that make them well suited for such applications.
As improved public health standards increase our average life expectancy, the occurrence of diseases associated with the aging process also becomes more prevalent. Thus, an understanding of the onset and progress of such afflictions becomes essential. A number of studies have revealed that changes in the brain associated with aging-related maladies such as stroke, Parkinson’s disease, sclerosis, and dementias can potentially be reversed through stem cell-based therapies. Obtaining consistent data regarding stem cell survival and distribution, however, has remained challenging. To address this issue, studies have employed superparamagnetic iron oxide nanoparticles (SPIONs) to label stem cells, enhancing in vivo imaging and facilitating stem cell tracking.
