In gel electrophoresis at pH 8.6, which lipoprotein has the highest migration rate?

At pH 8.6 in gel electrophoresis, the migration rate of lipoproteins is influenced by their charge and size. Pre-β lipoproteins, which primarily consist of very low-density lipoproteins (VLDL) and some low-density lipoproteins (LDL), are relatively small and possess a higher negative charge at this pH level compared to other lipoproteins. This higher charge allows them to travel further towards the anode during electrophoresis, resulting in a faster migration rate.

In contrast, chylomicrons are larger and have a lower charge at this pH, causing them to migrate more slowly. Similarly, β lipoproteins (mostly LDLs) and α lipoproteins (HDLs) are larger and less negatively charged than pre-β lipoproteins, thus migrating slower than pre-β lipoproteins in the gel.

Therefore, pre-β lipoproteins exhibit the highest migration rate in gel electrophoresis at pH 8.6 due to their combination of smaller size and relatively higher negative charge, allowing them to travel further compared to the other lipoproteins mentioned.