Apoferritin is a complex protein potential for drug delivery application. The advantage of apoferritin lies in its core-shell structure, its nano size, and its pH-sensitivity. This study was aimed to characterize the structure of apoferritin due to the pH alteration effect in a solution using dynamic light scattering (DLS) and small-angle neutron scattering (SANS). Both DLS and SANS can observe protein size in solution near its physiological condition. The results show that apoferritin possesses a core-shell structure with a diameter of around 12–13 nm at pH 7. The dissociation of apoferritin occurs at pH 1.9. The SANS data shows the apoferritin at pH 1.9 was dissociated into the smaller oligomer. The structure of this smaller oligomer has a different configuration than the configuration of apoferritin subunits at pH 7. It can cause the failure of reassembly of apoferritin if the apoferritin is neutralized back to pH 7 after dissociation from pH 1.9.

The prevalence of cancer in Indonesia is increasing and various cancer treatments still have shortcomings, cancer recurrence still occurs. Lymphoscintigraphy is a method for detecting disorders of the lymphatic system, which are closely related to cancer cells. Human serum albumin nanocolloid as a lymphoscintigraphic agent consists of particles measuring