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What is the polydispersity index?

Polydispersity Index (PDI) is a crucial parameter that describes the relative distribution of molecular sizes in a sample. Unlike substances with uniform molecular size, some materials, such as aggregates and biopolymers, exhibit a range of lengths and sizes. The PDI quantifies this variability, providing insight into the sample's heterogeneity.

A PDI value close to 1 indicates a uniform sample, where all molecules are nearly the same size. Higher PDI values signify a broader distribution of molecular sizes, indicating greater variability within the sample. Understanding PDI is essential in fields like polymer science and biotechnology, where the size distribution of molecules can impact material properties and functionality.