What is the Difference Between Coacervate and Microsphere

The main difference between coacervate and microsphere is that coacervate is an aqueous phase rich in macromolecules such as synthetic polymers, proteins, or nucleic acids whereas microsphere is solid or hollow and does not have a fluid inside.

Generally, coacervate and microsphere are two types of small particles important in different applications in science.

Key Areas Covered

1. What is Coacervate
   • Definition, Characteristics, Importance
2. What is Microsphere
   • Definition, Characteristics, Importance
3. Similarities Between Coacervate and Microsphere
   • Outline of Common Features
4. Difference Between Coacervate and Microsphere
   • Comparison of Key Differences               

Key Terms

Coacervate, Microsphere

What is Coacervate

Coacervate is a liquid droplet of macromolecules such as synthetic polymers, proteins, or nucleic acids. It forms through the liquid-liquid phase separation; it occurs in the dense phase in thermodynamic equilibrium with a dilute phase. Importantly, coacervates were described in the early 20th century by Bungenberg de Jong and Kruyt (1929). In the case of complex coacervation, associative interactions between multiple soluble molecules result in demixing into a polymer dense and a polymer diluted phase. In this, at least one of the soluble molecules is a macromolecule such as protein, DNA, RNA, and other polymers.

Figure 1: Coacervate Droplets

Complex coacervates occur through multivalent electrostatic interactions and therefore, they are responsive to environmental changes, such as pH, salt concentration, and temperature. Furthermore, the main function of coacervate is to emulate the dynamic organization of membrane-less organelles found in living cells. In addition, coacervates are important to form a microcapsule shell.

What is Microsphere

A microsphere is a spherical microparticle with a diameter of 1–1000 μm. Generally, biodegradable polymers are frequently used for the development of microsphere matrixes such as polylactic acid and copolymer of lactic acid and glycolic acid. Moreover, albumin, albumin dextran sulfate, and fibrinogen are important in the preparation of an extensive range of microspheres. 

Figure 2: Glass Microsphere

Furthermore, the main feature of a microsphere is that it is solid or hollow and does not have a fluid inside. Glass microspheres, polymer microspheres, metal microspheres, and ceramic microspheres are commercially available. In general, with surface modifications, microspheres are applicable in calibrations, labeling, flow cytometry, assaying, and more.

Similarities Between Coacervate and Microsphere

• Coacervate and microsphere are two types of microparticles and droplets.
• Generally, they have different applications in science.

Difference Between Coacervate and Microsphere

Definition

Coacervate refers to micro-droplets produced by liquid-liquid phase separation, and are increasingly used to emulate the dynamical organization of membrane-less organelles found in living cells, while microsphere refers to small spherical particles with surface modification for specialized applications, such as calibrations, labeling, flow cytometry, assaying, and more.

Significance

Coacervate is an aqueous phase rich in macromolecules such as synthetic polymers, proteins, or nucleic acids while the microsphere is solid or hollow and does not have a fluid inside.

Function

Moreover, coacervates emulate the dynamical organization of membrane-less organelles found in living cells while microspheres are important in calibrations, labeling, flow cytometry, assaying, etc.

Conclusion

In brief, coacervate is a microdroplet that occurs in the liquid-liquid phase separation. Usually, the droplet may contain synthetic polymers, proteins, or nucleic acids. The main function of coacervate is to emulate the membrane-less organelles in the cell. Microspheres, on the other hand, are solid or hollow particles with a diameter of 1–1000 μm. Moreover, glass microspheres, polymer microspheres, metal microspheres, and ceramic microspheres are commercially available. By modifying the surface, microspheres are applicable in many processes such as calibrations, labeling, flow cytometry, assaying, and more. Thus, this is the summary of the main difference between coacervate and microsphere.

References:

1. Coacervate. Coacervate – an overview | ScienceDirect Topics. (n.d.). Retrieved September 7, 2022.
2. Microsphere. Microsphere – an overview | ScienceDirect Topics. (n.d.). Retrieved September 7, 2022.

Image Courtesy:

1. “Coacervate droplets example ” By Spruijtlab – Own Work (CC BY-SA 4.0) via Commons Wikimedia
2. “DNA poly Glass microsphere in concrete” By Lylegordon at en.wikipedia – Own Work (CC BY 2.5) via Commons Wikimedia