Modern vaccines based on homogeneous subunit antigens are highly purified, which offer significant advantages over classical vaccines based on whole pathogens, enabling more precise targeting of the immune response and improved safety. However, such subunit vaccines are poorly immunogenic proteins, including feeble, short-lived immune responses. Immunoadjuvants are used to potentiate the activity of modern subunit vaccines that are based on molecular antigens.
https://www.creative-biolabs.com/vaccine/custom-adjuvant-synthesis.htm