Analytical techniques for characterization of VLPs. A series of analytical tools has been used for biochemical, biophysical and biological characterization of VLPs. Biochemical method: Matrix assisted laser desorption ionization time of flight-mass spectrometry (MALDI-TOF MS), liquid chromatography–mass spectrometry (LC–MS), sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and reverse phase-high performance liquid chromatography (RP-HPLC). Biophysical method: Transmission electron microscopy (TEM), cryo-electron microscopy (Cryo-EM), atomic force microscopy (AFM), asymmetric flow field-flow fractionation coupled with multiple-angle light scattering (AF4-MALS), electrospray differential mobility analysis (ES-DMA) and high performance size exclusion chromatography (HPSEC), dynamic light scattering (DLS), analytical ultracentrifugation (AUC), Circular dichroism (CD), differential scanning calorimetry (DSC), Cloud point. Biological characterization: Surface plasmon resonance (SRP), enzyme-linked immunosorbent assay (ELISA). MALDI-TOF MS and LC–MS images are reprinted with permission from Elsevier. SDS- PAGE and DLS images are reprinted with permission from Elsevier, RP-HPLC image is reprinted with permission from Elsevier, TEM, A4-MALS and ES-DMA images are reprinted with permission from John Wiley and Sons. Cryo-EM image is reprinted with permission from Elsevier. AFM is reprinted with permission from Elsevier, HPSEC, AUC, CD, DSC, Cloud point and SPR images are reprinted with permission from Elsevier.