ISSUES
Microbubbles are a fast approaching technology used for cancer, the environment, and additional drug therapy. With new technology, more research is required to fully evaluate the benefits that can be reaped from these contrasting agents. Many clinical trials are constantly being conducted, such as the Alzheimer's/Dementia case tested on mice, oncology treatments, and drug therapy trials. A 2018 clinical trial, "Sonoporation by microbubbles as gene therapy approach against liver cancer" CLICK HERE TO READ uses innovative technologies such as sonoporation to find solutions to difficult problems.
SOCIAL
Microbubbles need to be constantly researched and evaluated, many scientists doing so by conducting clinical trials. Subjects are often animals, sparking legal issues involving the testing and procedures many are subjected to. An example being Alzheimer's/Dementia case where mice were subjected to screenings and memory tests. Mice are often used for these tests for oncology. Some effects are listed as "inflamed mouse heart and kidneys, using a clinical ultrasound scanner" (Yeh.)
LEGAL
Microbubbles can be useful in a wide field of applications, however, many tools and resources would have to be used. By using microbubbles to counteract global ten thousand ships would have to inject 11,000 m3 of air a day, leading more fuel and emmission used. The resources used compared can further add to global warming instead of reverting it. Vortex mixers would also be necessary.
ETHICAL
TECHNICAL ISSUES
An obstacle involved with using micro bubbles is its longevity in the bloodstream. Most microbubbles once in the bloodstream disappear quickly due to arterial pressures and the increased in solubility of air in blood. As these microbubbles disspear quicker than they are intended for, its drug delivery impacts are reduced greatly. To counteract this problem, second generation microbubbles have been developed with new features. These new features include perfluorocarbons or sulfur hexafluoride while added phospholipids on the exterior increase a bubble's stability.
The size of microbubbles can serve as a problem. Although these agents are typically between 3 μm diameter wide, this size can be difficult to pass through epithelial cells. Due to the difficulty to pass through these cells, microbubbles can target specific sites. While this is an obstacle, scientists have found a solution. By using nanodroplets and nanobubbles that are smaller than one micrometer, more target tissue such as tumors can be targeted.
Another obstacle with the use of microbubbles are the various factors that can minimize the benefits of microbubbles. Frequency, pressure, and location are some pressing factors. Higher acoustic pressures cause microbubbles to defy compression rather than expansion. Additionally, higher acoustic pressures will cause the rupturing, compression, and expansion. Microbubbles when near the cell membrane can cause decreased stability leading to endocytosis. However, if microbubbles are put under lower acoustic pressure, the reflected frequency of is the same as the frequency transmitted.