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Self-interaction
Therapeutic success is dependent not only on how effective a molecule is inside a
patient, but also how efficiently it is delivered to patients. Therefore, when creating
clinic-bound biological therapeutics, it is important to consider the properties of
the biologic during storage or shipping, as well as for patient delivery. Formulations
that are highly viscous prove difficult to inject or deliver to patients, and biologics
that have a high propensity towards self-interaction are o en more likely to
aggregate over time.
Self-interaction can predict the long-term stability of a
biologic candidate
By measuring the change in r
H
versus concentration of a candidate, DLS
is capable of making a k
D
measurement. Here, k
D
is the self-interaction
parameter. This is a measurement of the affinity of your biologic to itself.
While formulating a biologic, it is generally better for it to be less likely to self-
associate, as this behaviour can ultimately lead to aggregation or different
oligomeric forms, which makes dosing and delivery difficult.
