Application of different analytical methods for the characterization of non-spherical micro- and nanoparticles

Quality Control of Protein Crystal Suspensions Using Microflow Imaging and Flow Cytometry

“…Meanwhile, MFI showed a larger size range for the amorphous aggregates (1–12 μm) and for the crystals (0.75–26 μm) compared to LO. Such differences between MFI and LO were reported previously while measuring standard polystyrene particles of different sizes and shapes . One possible reason is the lower accuracy of LO for particles smaller than 2 μm.…”

“…Flow cytometry was also used in this study. The use of this tool was described before in the context of protein aggregate analysis or contamination with silicone oil in biopharmaceutical products . The flow cytometer can measure large particle numbers in a very short time frame (up to 5000 particles/s).…”

“…Such differences between MFI and LO were reported previously while measuring standard polystyrene particles of different sizes and shapes. 13 One possible reason is the lower accuracy of LO for particles smaller than 2 :m. Due to the broad size distribution; identification of the crystals and amorphous aggregates based only on the particle size was not possible, as both groups overlapped. However, using the mean intensity allowed the identification of two separate populations based on the fact that the crystals appeared darker than the amorphous aggregates.…”

“…The use of this tool was described before in the context of protein aggregate analysis or contamination with silicone oil in biopharmaceutical products. [12][13][14] The flow cytometer can measure large particle numbers in a very short time frame (up to 5000 particles/s). This single-particle measurement method can analyze size ranges from 0.5 to 100 :m. To our best knowledge, this is the first reported use of flow cytometer for differentiation of protein crystals and amorphous precipitates.…”

3D material cytometry (3DMaC): a very high-replicate, high-throughput analytical method using microfabricated, shape-specific, cell-material niches

“…When scaled to a 20μL starting volume, this number of microgels jumped to ∼49,200, showing that collection efficiency was slightly higher with higher areas since mold edges were left empty to prevent film formation. Notably, the same shape/size/fluorescence (SSF) barcoding could be expanded further 28, 29 (Supplementary Figure 1) to non-imaging flow cytometers which are more widely available, have more fluorescent color channels, and can physically sort populations of interest. As imaging flow cytometers become more commonplace and more powerful, 3DMaC can similarly increase in multiplexing capacity to accommodate studies of even more materials and therefore is a promising way to improve biomaterials design.…”