Tag Archives: silk-diamond amalgam

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.

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.