As a follow-up to Monday’s post on optimizing nanoparticle design for nanotech drug delivery, the same research group has also demonstrated the advantages of a multistage approach in which micrometer-sized mesoporous particles are used to deliver two different nanoparticles in a way that circumvents some of the biological barriers that bedevil attempts to precisely deliver drugs where they are needed. From the University of Texas Health Science Center at Houston, via AAAS EurekAlert “Nanomedicine system engineered to enhance therapeutic effects of injectable drugs“:
Mauro Ferrari, Ph.D., of The University of Texas Health Science Center at Houston presented a proof-of-concept study on a new multistage delivery system (MDS) for imaging and therapeutic applications. This discovery could go a long way toward making injectable drugs more effective…
“This is next generation nanomedicine,” said Ferrari, the senior author. “Now, we’re engineering sophisticated nanostructures to elude the body’s natural defenses, locate tumors and other diseased cells, and release a payload of therapeutics, contrasting agents, or both over a controlled period. It’s the difference between riding a bicycle and a motorcycle.”
Nanotechnology offers new and powerful tools to design and to engineer novel drug delivery systems and to predict how they will work once inside the body. “The field of therapeutic nanoparticles began with tiny drug-encapsulated fat bubbles called liposomes, now commonly used in cancer clinics worldwide. Targeting molecules were later added to liposomes and other nanovectors to assist in directing them to diseased cells,” Ferrari said.
Getting intravenous agents to their intended targets is no easy task. It’s estimated that approximately one of every 100,000 molecules of agent reaches its desired destination. Physicians are faced with the quandary of increasing the dosage, which can lead to side effects or reducing the dosage, which can limit the therapeutic benefits.
The multistage approach, according to Ferrari, is needed to circumvent the body’s natural defenses or biobarriers, which act as obstacles to foreign objects injected in the blood stream. “To overcome this problem, we hypothesized and developed a multifunctional MDS comprising stage 1 mesoporous particles loaded with one or more types of stage 2 nanoparticles, which can in turn carry either active agents or higher-stage particles. We have demonstrated the loading, controlled release and simultaneous in vitro delivery of quantum-dots and carbon nanotubes to human vascular cells,” the authors write.
The research was published in Nature Nanotechnology (abstract).
—Jim
