Nanotech

Zinc Oxide Nanoparticles

If You Can’t Prevent Them, Destroy Them: Zinc Oxide Nanoparticles Allows Immune System to Kill Virus that Causes Genital Herpes

A vaccine for herpes has eluded scientists, mainly because the virus that cause herpes simplex 1 (HSV-1) and 2 (HSV-2)—one causes cold sores and the other causes genital warts and birth defects in newborns if a woman gives birth while infected, respectively—does not stay in the bloodstream where vaccines are most effective. Researchers from University of Illinois at Chicago, in collaboration with scientists from University of Kiel in Germany, have discovered that tetrapod-shaped zinc oxide nanoparticles, that they dubbed ZOTEN, are effective in preventing healthy cells from being “hijacked” by the virus, and allowing the body’s natural defense system to kill the virus before it spreads.

Herpes has a tendency to hide in the nervous system when dormant, where symptoms are treated with oral antiviral medications and topicals for genital warts in the case of HSV-2 to shorten the duration of the outbreak. HIV infection is three or four times higher when infected with genital herpes, and with increased use of medication drug resistance can occur with little methods to prevent future outbreaks.

ZOTEN nanoparticles are manufactured using a patented flame transport synthesis technology, and work by electrically attracting positively charged proteins on the surface of HSV-2 virus with its own negatively charged surface. Once bound, HSV-2 can’t infect healthy cells and are subject to dendritic cells—antigen-presenting cells of the immune system that takes processed foreign cells and “present” them to antibody-producing cells to create arsenal for complete destruction of the pathogen.

When tested on female mice swabbed with HSV-2 and then treated with an ointment with ZOTEN as well as without, fewer genital lesions were witnessed on mice treated with ZOTEN than without, with also less evidence of central nervous system inflammation, where the virus makes its hideout when inactive in the bloodstream. The immune system at work was also observed under high resolution fluorescence microscopy as dendritic cells attacked HSV-2 virus while being held by the zinc oxide nanoparticles.

Once safety and effectiveness is established for human use, a cream containing ZOTEN nanoparticles would be applied to vaginal just before sexual intercourse. If applied regularly as a preventive measure and a dose was skipped, scientists speculate there is enough protection from the built-up immunity.

HIV also has positively charged proteins on their outer surface, and the researchers hope to expand their treatment modality to encompass HIV prevention as well.

Heart Patch

Bionic Heart Patch Replaces Need for Cardiac Transplants for Patients with Irreparable Heart Damage

Scientists at Tel Aviv University (TAU) have created a bionic heart patch by melding human tissue and pliant electronics held together using latest nanotechnology to be used as a high-tech Band-Aid placed over irreparably damaged cardiac tissue, either through myocardial infarction (heart attack) or heart disease. The inventors claim it’s even better than regular cardiac tissue as the heart patch can remotely monitor heart rate, regularity of electrical impulses, and release medication as needed. Due to the supple nature of the materials, the patch can expand and contract, just like a normal heart, and then some.

Utilizing advanced nanotech provided by TAU’s Tissue Engineering and Regenerative Medicine Lab, the scientists have developed a fully operational proxy, or replacement, tissue to replace completely traumatized tissue. Only, it’s intertwined with flexible electrical cords and embedded with sensors so that when a patient feels unwell while relaxing at home, the patient’s physician can remotely login to a computer and assess the situation in real time and adjust the patient’s electrical firing or authorize the release of medications stored in the heart patch’s electroactive polymer to help stabilize the patient—without the patient having to move a muscle.

In the United States, 25 percent of Americans are on the waiting list for a heart transplant. While improvements in technology have procured artificial hearts and veritable organs are being grown in petri dishes, it will still be several years before they appear on the market. With the heart patch, the need for transplants can be eliminated as the broken version—though not entirely mended—can be fully functional.

The scientists are looking to extend their application of the heart patch to the brain for irreversible neurological disorders. In the fashion of true artificial intelligence, they hope to upgrade the electronic sensors within the patch so that any irregularities, e.g. heart rate, high levels of inflammatory mediators detected, can be automatically rectified without the prompting of a physician or a technician.

Gold Nanoparticle Blood Test

Gold Nanoparticle Blood Test Better at Detecting Prostate Cancer than Current Routine Method

A simple, easy-to-administer gold nanoparticle blood test, developed by a scientist at University of Central Florida (UCF), has proven to be better at detecting early stage prostate cancer than the prostate-specific antigen (PSA) test—the current routine method for prostate cancer screening.

A few drops of blood from a finger prick are mixed with gold nanoparticles that are 10,000 times smaller than a freckle. When a malignant tumor starts to grow within the body, the immune system generates antibodies, which serve as the basis of specific cancer biomarkers when testing for cancers. The gold nanoparticles attract these biomarkers, which clump together and grow in size.

Among the scientific community, gold nanoparticles are well known for their ability to absorb and scatter light efficiently. A team of researchers at UCF’s Nanoscience Technology Center developed a technique called nanoparticle-enabled dynamic light scattering assay (NanoDLSay) that evaluates the size of particles by measuring the amount of light that emanates from them. Greater the size of the particle, the greater the light measurement, which is an indicator whether a male patient has prostate cancer and how advanced it may be.

Preliminary studies indicate with 90 to 95 percent confidence results from the gold nanoparticle blood test are not false-positives compared to the PSA test, with a 50 percent confidence for false-negative results, which are considered not great but better than 20 percent with PSA. The research team is working on improving that value. Currently, the PSA test tends to procure more false-positive results that lead to more invasive procedures which can potentially be eliminated with the new test.

Even though gold is the core ingredient to run the test, a small bottle of nanoparticles suspended in water costs $250, which is enough to administer 2,500 tests, essentially rounding out the test cost to less than a dollar.

After more extensive clinical studies, long-term goal is to have patients undergo prostate cancer screenings with the gold nanoparticle blood test in physician offices, and possibly expand the reach of the new test into a universal cancer screening protocol for a wide variety of tumors.

3D-Printed Facial Prosthetics

3D-Printed Facial Prosthetics an Inexpensive Option after Undergoing Eye Surgery

A professor of ophthalmology at the Bascom Palmer Eye Institute in Florida, in conjunction with the Composite Materials Lab at University of Miami, has come up with a new method to create 3D-printed facial prosthetics that can be made within minutes at the fraction of the cost of a traditional prosthesis. Its nanoclay material prevents it from breaking down when exposed to light and moisture and prevents dirt from taking root in the prosthetic.

Facial prosthetics can cost upwards of $10,000 to $15,000 and take weeks to produce. They’re made by an ocularist who takes a mold of the face and casts it using rubber. Final touches, such as skin color, and fine details, such as individual eyelashes, are performed. They’re usually not covered by health insurance and patients often have to pay out-of-pocket.

People with eye cancer may undergo a lifesaving procedure called exenteration that removes the contents of the eye socket along with surrounding tissue, leaving a hollow socket. Conventional facial prosthetics are expensive, take a long time to make, and can discolor and fray at the edges over time.

A topographical imaging system scans both the unaffected and affected sides of a patient’s face. The software creates a mirror image with the undamaged portion, which is combined with the scan of the affected side to create a 3D rendition of the face. A 3D printer takes the topography information and translates it into a mask formed out of rubber infused with nanoparticles that enable it to match a variety of skin tones, as well as strengthen the rubber material to weather damaging effects of light and moisture.

Since the topography imaging is performed with a mobile scanner, the scientists plan to create 3D-printed facial prosthetics on location where the patient resides, have the data downloaded in Miami, print out the prosthesis, and have it shipped to the patient the next day.

Microneedle-Covered Capsule

Promising Microneedle-Covered Capsule to Supersede Injections?

A swallowable microneedle-covered capsule—approximately 2 centimeters long and 1 centimeter in diameter—was devised by Massachusetts Institute of Technology (MIT) researchers, working with Massachusetts General Hospital (MGH), as a way to deliver medications orally and perhaps replace injections in the future.

The prototype pill is made of acrylic—serving as a medication reservoir—and encased with tiny hollow stainless steel needles (5 millimeters in length) that are designed to “inject” drugs directly into the stomach lining. Large medications, usually consisting of proteins, are not readily absorbable and thus degraded in the stomach and rendered useless before it can be absorbed. Insulin was tested in pigs using the microneedle-covered capsule technology and was found to lower blood glucose levels more effectively than subcutaneous insulin injections.

However, the capsule took longer than a week to go through the digestive tract and evidence of tissue damage was not apparent. The scientists also claim the gastrointestinal (GI) tract has no pain receptors so no discomfort is felt as the microneedle-covered capsule moves through the GI canal.

The new medication delivery mechanism may be better suited for injecting into the gut a class of drugs called biologics that include vaccines, recombinant DNA, RNA, and antibodies, such as those for autoimmune diseases like arthritis and Crohn’s disease that often require intravenous infusions to ensure effective drug delivery.  Nanoparticles and microparticles were originally engineered for oral medication delivery for biologics but they are expensive to manufacture and a new system has to be created for a different drug. With the microneedle-covered capsule, the researchers are aiming for a universal delivery system that can be reproduced for different drugs inexpensively.

To ensure absolute safety, the scientists are working on replacing the stainless steel needles with digestible polymers and sugar that would continue to release medication into the GI lining once it breaks off from the capsule and lodges itself into the gut as it decomposes.

Intraocular Pressure Monitoring Implant

New Intraocular Pressure Monitoring Implant for Glaucoma Sufferers

Scientists at Stanford University and Bar-Ilan University in Israel have developed an intraocular pressure monitoring implant to help glaucoma patients check their own internal eye pressure whenever they want without constant visits to the ophthalmologist. Even with frequent checkups, pressure can rise ominously high between visits.

Glaucoma is an eye disease characterized by damage to the optic nerve from constant exposure to increased internal eye pressure caused by fluid buildup within the eye, although there are forms of glaucoma that develop without increased intraocular pressure. If left untreated, vision loss occurs, and depending on the extent of damage to the optic nerve, even blindness. Depending on the type of glaucoma, there are no symptoms during the beginning stages. As the disease progresses, peripheral vision is the first to be affected. Glaucoma is the second-leading cause of blindness in the world and there is no cure.

Treatments are tailored to prevent further vision loss, if any; thus, early intervention is important. They range from medicines, such as eye drops, to decrease internal eye pressure to laser trabeculoplasty to help drain fluid out of the eye.

The new intraocular pressure monitoring implant is currently designed to be encased in a lens prosthetic that cataract patients undergo to restore vision, which glaucoma sufferers end up having done. The implant consists of a sensing channel (in the form of a minute transparent tube), with an opening at one end and covered by a gas-filled chamber on the other end. If the internal eye pressure increases, fluid is squeezed into the tube. The gas pushes back, creating a fluid-gas barrier in the sensing channel that can be viewed externally. With the aid of a smartphone camera and an app, the intraocular pressure level can be determined based on the position of the barrier in the tube. If the pressure level is dangerously high, a specialist should be consulted. Trial tests have shown the implant does not obstruct vision.

The scientists are working on engineering a standalone intraocular pressure monitoring implant and hoping to have the new model undergo clinical trial in a few years.

Functional Bioengineered Vaginas

Medical scientists recently announced the indelible success of bioengineered vaginas that were implanted into four teenage girls—a first in the ever-expanding field of regenerative medicine. The research project was led by a physician from Wake Forest Baptist Medical Center’s Institute of Regenerative Medicine in North Carolina.

The subjects were females between 13 and 18 years of age who were born with Mayer-Rokitansky-Kuster-Hauser (MRKH) syndrome, a rare genetic condition that only affects newborn girls in which the uterus and vagina are underdeveloped or entirely absent. The bioengineered vaginas, derived from the patients’ own muscle and epithelial cells which were sampled from their external genitalias, were surgically implanted between June 2005 and October 2008.

The extracted cells were expanded, or cultured to replicate, and placed on a biodegradable “scaffold” that’s been hand-shaped into a vagina-like structure tailored to the individual subject. Approximately 5-6 weeks after cells were extracted from patients, the seeded scaffolds are sewn into patients’ pelvis where a man-made canal was dug. Nerves and blood vessels form and the scaffold cell seeds proliferate into tissue. As the scaffold is absorbed into the body, the cells continue to expand to lay down a permanent support structure that will become the new “organic” vagina.

Based on yearly follow-up visits, MRI scans, tissue biopsies, and internal exams using magnification equipment, the bioengineered vaginas were more or less indistinguishable in form and function to native tissue. Moreover, the subjects’ answers to the Female Sexual Function Index questionnaire revealed they had normal sexual function after surgery, including desire, arousal, and pain-free intercourse.

Current treatments for MHRK syndrome involve dilating existing vaginal tissue or vaginal reconstructive surgery. Skin grafts or abdominal tissue are usually used for the reconstruction but they lack muscle and the new vaginal graft has a tendency to narrow or contract which then requires dilation.

With more clinical experience and an established surgery protocol, the team is hoping to expand the application of implanted bioengineered vaginas to patients with vaginal cancer or incurred vaginal trauma injuries.

Silk-Encased Fluorescent Nanodiamonds May Hold Key to Precise Medication Delivery

Scientists from Australia and the United States have discovered a new method to safely view the internal workings of a cell and potentially target a region in the body for precise medication delivery by using silk-encased fluorescent nanodiamonds.

Diamonds are solid substances that are comprised of geometrically organized carbons—the basic atoms of life—and thus stable and harmless. The tiny diamonds can be inserted into living cells and, based on the “flaw” in the gem, absorb light and then emit that light in different wavelengths depending on the material in the nanodiamond—a process called fluorescence.

Silk was incorporated as a coating because the edges around the gem are rough and can get snared in the cell membrane. Lipids, organic molecules found in fats and the basis of cell membrane structure, were originally used to counteract the rough edges, but silk was the better choice due to its transparent, flexible, harmless, and biodegradable nature.

When tested on living tissue, the team of researchers found the “glow” from the silk-encased fluorescent nanodiamonds were 2-4 times brighter because of the silk material and was found to be nontoxic and non-inflammatory, after it left no damage in its wake in the body even after it remained implanted for two weeks.

Silk-encased fluorescent nanodiamonds can equip physicians and researchers with a new approach to viewing cellular activity as it reacts to a new drug. They may also carry medications, such as antibiotics, to a targeted region of the body by having the silk-diamond amalgam directly implanted into the infected area and decrease overall body toxicity levels. The silk, in addition, can be arranged to deteriorate at a predetermined rate for timed-release medication delivery.

Because of their “glowing” nature, silk-encased fluorescent nanodiamonds are lighting the way in the fields of bioimaging, biosensing, and drug delivery mechanisms, and the team hopes to incorporate their findings in medical practice soon.

Can ‘Broken Hearts’ Be Mended After a Heart Attack?

After a myocardial infarction (MI), or heart attack, the heart is never the same again. Dead cardiac tissue from insufficient oxygen perfusion is dissolved by the body and replaced by scar tissue that renders the heart less flexible. Thus, the heart muscles pump blood to the rest of the body less efficiently than its pre-MI state.

Scientists have come up with a number of ways to replace cardiac scar tissue by way of a ‘Band-Aid’ that helps regrow heart tissue. One method is the creation of MeTro, a gel made by tropoelastin, which is a protein that gives tissue its elasticity. The gel was “seeded” with cardiac muscle cells procured from the patient. The hope is that once placed onto the weakened area of the heart, the cells on the MeTro will merge with the patient’s cells via cell-to-cell communication mechanisms until the gel is completely replaced.

Another approach is the use of a carbon nanofiber patch with a 3D scaffold-like structure that can expand and contract like the heart. The fibers are proficient electricity conductors and can transmit electrons, or electrical impulses, that the heart requires to beat steadily. The combined elastic nature of the structure and its ability to conduct electrons make the nanofiber patch a good breeding ground for cardiac muscle cells, and thus excellent fodder for regeneration.

The latest discovery to heal the heart came from the help of lab rats. Scientists noted that the extracellular matrix (ECM) fibers in hearts of rats were spiral-shaped. The scaffold structures serve as the ECM in which to grow heart cells and were usually grown in labs as straight fibers. The fibers were spun using electrospinning techniques so they resembled telephone handset cords, and functioned like natural cardiac tissue compared to the straight fibers.

Once researchers refine the various artificial growing media for cardiac tissue regeneration and find a way to obtain large enough samples to use as seeds of regeneration, the path to mending broken hearts seems to be highly probable.

Gold Nanoparticles for Targeted Medication Delivery and Cancer Treatments

Cells are notoriously protective and do not easily allow particles entry into its domain unless unique transport mechanisms that the cell recognizes are in place. As a result, current medications and treatments do not target specific cell contents and end up destroying the entire cell.

In 2008, researchers discovered gold nanoparticles coated with a one-layer polymer can penetrate cell walls, and since then has recently identified the mechanism of action along with the upper size limit of the particle to effectively penetrate cell walls.

Through a series of lab experiments and computer simulations, researchers at MIT and the Ecole Polytechnique de Lausanne, Switzerland demonstrated the critical step of gold nanoparticles infiltrating the cell wall is to fuse with the phospholipid bilayer of the cell membrane, which is largely the responsibility of the coating on the particle. The coating is a mixture of hydrophobic (“water-fearing”) and hydrophilic (“water-loving”) compounds. Depending on the chemical nature of the compounds used, the upper size limit of the coating was also determined.

A bonus to the team’s discovery was that the method of delivery of gold nanoparticles also sealed the opening after its entry, preventing leaks behind the particle as well as inhibiting damage to the cell as the particle proceeded to the cell’s interior.

The team is hoping to use their discovery as a means of delivering drugs to the cell’s interior by attaching the drugs to the particle’s lipid-mixture coating once they find a way for the coating to be selective on what types of cells they attach to for targeted medication delivery.

The choice to use gold as the coating’s delivery instrument was simply convenient as a research model. However, the team has postulated on a potential health benefit of the precious metal. Gold particles are very good at absorbing x-rays. If the coating can be used to penetrate cancer cells, then the particle can be heated up by an x-ray beam and destroy the malignant cells from within.