![dynamic light scattering protein aggregation dynamic light scattering protein aggregation](http://www.soft-matter.uni-tuebingen.de/images/SAXS.jpg)
You can also use the r H as an indication that conjugation was successful, as there is very likely to be a difference in size between the conjugated and unconjugated mAb. With DLS, you can ensure that the mAb survived the conjugation process by examining the PDI and determining whether there are large aggregates formed as a result of the harsh chemical treatments. The conjugation process can be tough on a mAb, and it is often crucial to ensure no unconjugated material remains. This requires conjugation of the medicine to the mAb. In this case, the mAbs target a receptor or protein of interest in a diseased or damaged cell, and they bring the medicine with them. With the advent of personalized medicine, there is a huge sub-market of biologics interested in using biologically-derived molecules like monoclonal antibodies (mAbs) to deliver small molecules, peptides, or gene therapy nucleic acids only to specific areas in the body. Most developers look for a negative slope, which is a good indication that a protein will not aggregate at higher concentrations. This information is derived from plotting the diffusion coefficient vs. Many drugs are stored and delivered to patients at higher concentrations.ĭLS can help you predict how your biologic will behave at different concentrations with its ability to measure self-interaction, or k D. However, it’s important to note that the concentration of a biologic candidate can have a huge impact on its ultimate efficacy. A reduced PDI due to mutations indicates more single, well-folded species of proteins, and is generally a desired outcome for long-term success of a candidate.Įarly discovery and development work is often done with very small sample amounts, due to cost-effective limitations in the lab. Look at how the dispersity (PDI) changes.
![dynamic light scattering protein aggregation dynamic light scattering protein aggregation](https://image.slidesharecdn.com/a4ea3e4a-14fd-481e-b9f9-bba4bc19198f-161001160837/95/optimization-of-a-test-arrangement-for-dynamic-light-scattering-measurement-in-flow-and-characterization-of-uvinduced-aggregation-of-the-prion-protein-49-638.jpg)
When it comes to DLS data, compare the mutated candidate to its parent. Mutations are made by swapping out one amino acid for another - this switch can be rational, such as when trying to enhance antigen binding by increasing ionic bonds or random, to try to determine what changes can be made to a structural region to enhance its stability. Making mutations to a protein’s primary structure is the bread and butter for many protein engineers. Let’s take a look at some of the typical changes a protein biologic can undergo, and how these affect the DLS read-out. If you’re struggling to optimize a candidate, it’s necessary to make some formulation changes to improve its odds of making it successfully to market. This data is obtained from dynamic light scattering, or DLS experiments. When considering some of the earliest parts of the biologic development cycle, two parameters that many researchers rely on are particle size and dispersity in solution. However, the reality for biologics researchers is that formulation is a multi-step process that considers the entire development of a biologic candidate, from early discovery to delivery to a patient. Formulation typically refers to the final development of a deliverable, biologically derived molecule (such as a protein, peptide, nucleic acid, or small molecule) as it goes to market. Biologics researchers are deeply concerned with formulation.