The development of nanotechnology in medicine is a longer-term process than nanotechnology in general. The reason is that the application of any technology, device, or medicine to humans has an involved process with many steps that require a long time to demonstrate the ability to pass all the various regulations.
This month’s blog will look at developments in the last few years in three areas: 1) cancer treatment; 2) application impacting the heart; and, 3) the eye.
Cancer treatment has been a key research area since before 2000. Initial work involved the use of attaching gold nanoparticles to certain types to viruses. Caner cells are hungry and will devour various types of viruses. By inserting gold nanoparticles into preferred viruses, the cancer cells would grab the them and try to consume them. By illuminating with IR radiation, the site with a concentration of viruses with gold encapsulating inside then, the temperature of the virus and cancer cell can be raised to a high enough temperature to kill the cancer cells. In a similar approach, encapsulating carbon nanotubes in the viruses, exposure to RF waves converts the radiation into heat efficiently and kills the cancer cells. Where are we today in early 2018?
In January 2018, the Seoul National University Hospital indicated that it has developed a new magnetic nanoparticle that can be employed to improve the therapeutic benefits for the treatment of cancer. The application of a magnetic field causes the nanoparticles to heat, which causes the cancer cells to be killed. The claimed benefits are that the treatment can be focused to the specific cancer cells and basically leave the surround healthy cells without damage. The claim in the latest work is that the magnesium nanoparticles developed are able to heat much faster that previously developed ones, which minimized the amount of energy to heat the nanoparticles (temperatures a high at 50C could be required) that is required. An additional advantage is that the nanoparticles contain identical components as a previously FDA approved iron oxide nanoparticle. [Ref. 1]
As I was proofing this blog, I received an article from the R&D Magazine that provides a history of the direction of cancer treatment. [Ref. 2] “Today there are about 20,000 papers written on this topic each year. A lot of researchers are starting to work in this area and we (the National Cancer Institute – NCI) are receiving large number of grant applications concerning the use of nanomaterials and nano-devices in novel cancer interventions. In last three years there has been two FDA approvals of new nanoparticle-based treatments and a multitude of clinical trials.” I recommend reading it.
Addressing heart issues through the application of nanotechnology. A nanoparticle developed by University of Michigan researchers could be the key to a targeted therapy for cardiac arrhythmia, which impacts 4 million Americans each year with a resulting 130,000 deaths. Cardiac arrhythmia is a condition that causes the heart to beat erratically and can lead to heart attack and stroke. Currently, the disease is treated with drugs, with the possibility of serious side effects. Cardiac ablation is also employed, but the effect of a high powered laser damages surrounding cells. The current work, not yet done on humans, kills the cells causing the problem without damaging the surrounding cells. [Ref. 3]
There is also work being done in cryogenically freezing and rewarming sections of heart tissue for the first time, in an advance that could pave the way for organs to be stored for months or years. By infusing tissue with magnetic nanoparticles, frozen tissues can be heated in a excited magnetic field, which generates a rapid and uniform burst of heat. Most work on warming tissue samples have run into problems with the tissues shattering or cracking. If this can be fully developed, the availability of transplanted organs becomes much better. Donor organs start to die as sooon as the organ is cut off from the blood supply. Possibly as much as 60% of the possible donor organs are discarded because of the four hour effective ice cooling limit of organs. [Ref. 4]
Pioneering nanotechnology research has applications for cardiovascular diseases. Samuel Wickline, MD, the founding director of the USF Health Heart Institute, has been harnessing nanotechnology for molecular imaging and targeted treatments. They have developed nanostructures that can carry drugs or exist as therapeutic agents themselves against various types of inflammatory diseases, including, cancer, cardiovascular disease, arthritis and even infectious diseases like HIV. [Ref 5]
Treatment of the eye has a number of needs. Typically, less than 5% of the medicine dose applied as drops actually penetrates the eye – the majority of the dose will be washed off the cornea by tear fluid and lost. Professor Vitaliy Khutoryanskiy team has developed novel nanoparticles that could attach to the cornea and resist the wash out effect for an extended period of time. If these nanoparticles are loaded with a drug, their longer attachment to the cornea will ensure more medicine penetrates the eye and improves drop treatment. The research could also pave the way for new treatments of currently incurable eye-disorders such as Age-related Macular Degeneration (AMD) – the leading cause of visual impairment with around 500,000 sufferers in the UK. While there is no cure for AMD, experts think its progression could be slowed by injections of medicines into the eye. This new development could provide a more effective solution through the insertion of drug-loaded nanoparticles. [Ref. 6]
A coming generation of retinal implants that fit entirely inside the eye will use nanoscale electronic components to dramatically improve vision quality for the wearer, according to two research teams developing such devices. Current retinal prostheses, such as Second Sight’s Argus II, restore only limited and fuzzy vision to individuals blinded by degenerative eye disease. Wearers can typically distinguish light from dark and make out shapes and outlines of objects, but not much more. The Argus II contains an array of 60 electrodes, akin to 60 pixels, that are implanted behind the retina to stimulate the remaining healthy cells. The implant is connected to a camera, worn on the side of the head, that relays a video feed. [Ref. 7]
The above descriptions are only the tip of an iceberg. There a much work being done around the world. There have been an interesting series of articles on the development of various medical technologies that are joint university efforts with the teaming of both US and Chinese universities.