What are the Applications of Ultrasound Sonochemistry in Medicine?

 

Ultrasonic can be used in chemistry to increase reaction rates and product yields. The majority of the impact of ultrasound on chemical reactions is due to cavitation: the formation and rupture of small bubbles in solvents. In this review, we first provide an overview of the physical background of cavitation and discuss its dependence on factors such as sound intensity and frequency, solvent, and temperature. The influence of ultrasound on chemical reactions is considered for both homogeneous and heterogeneous liquid-solid systems. The first field is mainly illustrated by discussing the influence of ultrasound on polymerization and depolymerization reactions, while the second field is illustrated by selected examples in organic synthesis. We also briefly discussed the trend of ultrasound altering the reaction mechanism to support the homogeneous (rather than heterogeneous) pathway. The specific preference for a particular path under sonochemical conditions, different from the path under mechanical stirring, is called "sonochemical conversion". Compared ultrasound equipment used for laboratory scale experiments and provided some practical "techniques and traps".

 

Ultrasonic disruption and lysis of cells

 

Ultrasonic sonochemical equipment is mainly used for sample preparation and production. These fields particularly include homogenization, emulsification, and suspension of various substances, as well as acceleration of chemical reactions, cell lysis, and extraction of cell contents. The use of ultrasonic sonochemical equipment can selectively destroy certain substances, shorten tedious preparation processes, and improve the yield of many reactions. Comparison with mechanical processing equipment such as planetary ball mills, rotors/stators, or gap homogenizers shows that ultrasonic sonochemical equipment works with higher efficiency, especially making reproducible results possible. The trend of analysis is that the sample size is getting smaller and the use of chemicals is also decreasing. For example, in recent years, the use of ultrasonic sonochemical equipment has become crucial, as even the smallest sample sizes require fast, economical, and reproducible processing.

 

 

Destruction of cells and microorganisms

 

In modern laboratories, ultrasonic sonochemical equipment is used to break down cell walls to extract cell contents, such as proteins, without damaging them. A portion of the energy introduced into the cell suspension is converted into heat through friction. In order to avoid thermal damage to the cellular contents, the sample is either subjected to intermittent ultrasound treatment periodically or cooled in a cooling container during ultrasound treatment. The rose pond can uniformly treat microorganisms with ultrasound because the ultrasound energy forces the sample to circulate repeatedly under the probe and throughout the side arm. Placed in an ice bath, the glass surface expands and effectively cools the contents.

 

The destruction of cell membranes largely depends on the elasticity of cells. Cellular components, such as mitochondria or cytoplasm, can be partially disrupted by altering the input ultrasound energy and extraction power. For particularly drug-resistant bacteria (such as streptococcus), fungi, spores, yeast, or tissue samples, direct destruction can be achieved with very high ultrasound amplitudes using microtubes, as microtubes can input very large amounts of energy into the smallest sample size.

 

When using microliters, foam and splash in the container are a bigger problem. May cause loss of valuable sample materials. Therefore, power regulation is very important. If you want to destroy cells with unstable walls, only a small amount of power or amplitude is needed. In order to continuously dissolve in large quantities, a special flow container made of glass or stainless steel with an ultrasonic chamber is used to treat each particle of the suspension with the same strength. If the container is equipped with an additional cooling jacket, it can eliminate thermal damage to the cell contents. In order to avoid contamination by foreign particles, such as erosion particles from probes, indirect ultrasonic treatment is preferred in cup boosters or cup horns. This method achieves uniform strength and cooling.

 

 

Applications in Biochemistry and Medicine:

 

Destruction of Organizational Cultivation

 

Subcellular components and viruses were disrupted without any damage.

 

Parent child testing

 

Quickly extract matrix free hemolysis from the assumed father's EDTA blood for paternity testing (reducing preparation time by approximately 30 minutes).

 

Urology Surgery

 

Biochemical membrane analysis of sperm composition.

 

Genetic research

 

Extract DNA from human body materials.

 

Liposome preparation

 

The use of ultrasound (20 kHz) to decompose MLV (multilayer liposomes) is the main method for producing SLV (monolayer liposomes).

 

The treatment of smallpox vaccine

 

Prepare a uniformly distributed infection solution.

 

Dispersed

 

With the help of ultrasonic energy, solid particles or even liquids can be dispersed into another carrier. Nanoscale powders, such as titanium dioxide or pyrolytic silica, are increasingly being used in the production of test paints and coatings, or for polishing the surfaces of small car bodies, due to their large specific surface area and continuously increasing reaction potential. In addition, these substances have an unfavorable tendency to aggregate, resulting in decreased fluidity and wettability. The formed agglomerates are disrupted by an ultrasonic homogenizer and the dispersion is permanently stabilized to prevent re agglomeration.

In particle size analysis, dispersion is crucial for the measurement process. Particles can only be identified during the measurement process and appear as detectable measurement signals in the measurement area. Therefore, undispersed agglomerates lead to significant erroneous measurements. With the help of ultrasound, particles are subdivided to prepare for subsequent measurements.

When ultrasonic emulsification is used, two immiscible liquids such as oil and water are processed into quasi homogeneous lotion. Compared with traditional methods using rotors, ultrasound can produce finely dispersed lotion with very small droplet size and very high stability. Neither the formation of clumps or clusters nor the settling of droplets occurs. When using traditional methods such as rotors or stirrers, slow stirring often leads to liquid separation. Mixing too quickly can cause unwanted air inclusions. Ultrasonic homogenizers are commonly used in pharmacies for high-quality small-scale production of ointments.

In our daily life, we will encounter many different forms of ultrasonic homogenized lotion, such as in cosmetics or lotion.

 

Homogenization

 

The application scope of ultrasonic homogenization technology ranges from the production of paints and varnishes to the homogenization of wastewater and soil samples for analytical purposes, and then to sample preparation for particle size analysis. Especially for industrial wastewater, it is constantly checked in environmental laboratories for the presence of heavy metals, fats, or oils, in order to take immediate measures when the concentration exceeds the standard. For representative analysis results, it is necessary to transform the wastewater sample into a homogeneous state. This is achieved through ultrasonic homogenization with high reliability in a very short period of time.

In order to characterize the landfill potential and pollutant assessment of waste samples, such as PAH (polycyclic aromatic hydrocarbons), heavy metals, or MKW (mineral oil hydrocarbons) in soil, ultrasonic extraction is used as a rapid homogenization process as an alternative method for elution.

In agriculture, ultrasonic homogenizers are used for sample preparation to subsequently determine the THC content in cannabis and the PAH concentration in vegetable foods (such as strawberries) based on soil load.

 

Ultrasonic homogenizers are often used for food quality control. In order to meet the limit, the nitrate content of cheese must be measured in the laboratory. The previous method of using xylenol methanol distillation and subsequent photometry was very problematic in toxicology and particularly time-consuming. Therefore, in order to quantitatively determine the nitrate content, or mechanically pre crush the cheese. Then, in a short period of time, ultrasound was used to perform dense and fine homogenization in the rosebud cells. The achievable particle size is less than 1 μ m, and due to the absence of aggregate formation, it greatly facilitates subsequent filtration to quantitatively wash out ions.