Latest Scientific Developments in the Field of Nanoparticle Dispersion Methods
As the name suggests, nanoparticles are minute entities with measurements in the order of 10-9 metres. Depending on their size range, they are further classified as- ultrafine, fine and coarse. The smaller the dimension of the particle, the greater is the total free surface area and hence, the better is the nanoparticle activity.
These nanoparticles are extremely promising objects with diverse range of applications in electronic, optical and biomedical fields and thus tap the interest of the scientist community all over the world. Be it for research or practical utilization in day to day life, implementation of nanoparticle dispersion methods is inevitable.
Popular nanoparticle dispersion methods
There are three primary approaches in nanoparticle dispersion methods. The selection of the most suitable technique depends on the state of solubility of the nanoparticle itself.
If the nanoparticle is used in aqueous phase, the use of ultrasonic waves is the most effective way for its dispersion. This technique is very effective as well as cheap. Moreover, guidelines for applying this strategy should be strictly followed to prevent overshooting of temperature and ensure nanoparticle structure is maintained. Also, probe integrity should be thoroughly checked before use because disintegration can contaminate samples irreversibly.
If the nanoparticle is used in non-aqueous or oil phase, utilizing a stirrer or high sheer mixing instrument like magnetic stirrer, overhead stirring paddle and homogeniser can prove to be the most appropriate method for dispersion. While using magnetic and overhead stirrer is affordable and there is minimal breakdown of nanoparticles, some inefficiencies such as re-aggregation form a major hurdle in their wide application. Hence, high speed and high pressure homogenisers have evolved as the next alternative. However, their use for longer than prescribed duration can raise temperature to levels that alter nanoparticle architecture.
If it is used in a dry powder form, application of the ball mill method for nanoparticle dispersion is undoubtedly the best choice of a dispersion strategy, when used for large batches. It employs an ultrafine grinding process for obtaining the desired outcome. This method is slow and may take several days to produce results. Also, grinding can lead to significant breakdown of nanoparticle architecture.
Practical Challenges Faced in Application of the Commonly Known Nanoparticle Dispersion synthesis
Nanoparticles pose threats both medically and environmentally, owing to their exceedingly small measurements. They provide an exceptionally high surface to volume ratio, thereby making them super reactive entities. In living systems, they can easily cross the cell membrane and bring about deadly consequences. Therefore, any kind of handling, including implementation of methods of nanoparticle dispersion, should be done with utmost precaution.