Drug Dlivery-Virus-like Particles

Virus-like particles (VLPs) are considered natural nucleic acid nanomedicines, in which nucleic acids (drugs) are encapsulated within a viral empty shell (drug carrier). Through nucleic acid staining, we can rapidly distinguish complete viruses, viral empty shells, free nucleic acids, etc., from the compounds. This allows us to further assess drug encapsulation efficiency, quantity, and the proportion of effective drugs.

The nucleic acid dye SYTO™ 82 was used to stain the viral (or vector) genome, and a laboratory-built nano-flow cytometer (nFCM) was employed to simultaneously detect the side-scatter and fluorescence signals of individual viral particles. Using the bacteriophage T7 as a model system, intact virions were completely discriminated from empty capsids and naked viral genomes. Successful measurement of the physical virus titer and purity was demonstrated for recombinant adenoviruses, which could be used for gene delivery, therapeutic products derived from phage cocktails, and infected cell supernatants for veterinary vaccine production.

Figure 1. Differentiation of intact virions, empty capsids, and free viral DNA.

Angew. Chem. Int. Ed., 2021, 60, 9351-9356.