Hassle-free nanoparticle characterization with Stunner

Importance of the topic

Payload concentration and particle size are critical parameters in nanoparticle research, directly affecting delivery efficiency and therapeutic performance. Accurate, non‐destructive, and rapid characterization methods support the development of gene therapies, vaccines, and drug carriers by reducing assay complexity and resource consumption.

Objectives and overview of study

This application note introduces Stunner, a platform integrating UV/Vis absorbance with dynamic light scattering (DLS) to simultaneously quantify payloads (RNA, DNA, protein, small molecules) and determine nanoparticle size and polydispersity. The aim is to demonstrate high‐throughput, low‐volume workflows for a broad range of nanoparticle formulations.

Methodology and instrumentation

Nanoparticles were prepared with defined lipid compositions (DOTAP:POPE:Chol:DMG‐PEG) using a NanoAssemblr® Ignite microfluidics system. RNA, DNA, and lysozyme LNPs were produced at various N/P ratios and buffer‐exchanged into PBS. Doxorubicin‐loaded and empty liposomes were obtained commercially and diluted in series. A Stunner instrument combining short‐pathlength UV/Vis and DLS measurements processed 2 µL samples in SBS‐format plates. UV/Vis absorbance spectra were deconvoluted by the Unmix algorithm; DLS acquisitions used 5-second runs at 20 °C with known buffer refractive index and viscosity. Gold nanoparticle standards validated DLS sizing.

Main results and discussion

Stunner’s LNP applications achieved linear quantification across 2-fold dilution series for RNA, DNA, and protein payloads with R²>0.99 and CVs<5%. Lipid & buffer absorbance at 230 nm also showed strong linearity (R²>0.92). DLS sizing matched gold standards (e.g., 59 nm standard measured as 57±2.1 nm) and detected size variations correlated with payload loading. Custom Nanoparticle analysis of doxorubicin mixtures yielded accurate payload measurements (R²>0.99) while tracking shifts in hydrodynamic diameter and polydispersity. These results confirm reproducibility, precision, and rapid throughput (up to 96 samples/hour).

Benefits and practical applications

• Non‐destructive, label‐free quantification without standard curves or detergents
• Simultaneous payload and size measurement from 2 µL samples
• High throughput suited for formulation screens and QC
• Regulatory compliance with Pharmacopeia standards and 21 CFR Part 11 support

Future trends and possibilities

Expanding the spectral database for novel payloads and complex formulations will extend Stunner’s applicability. Integration with automated liquid‐handling platforms can further increase throughput. Adoption in pharmaceutical R&D and manufacturing QC promises to accelerate nanoparticle product development and regulatory approval processes.

Conclusion

Stunner offers a streamlined, versatile workflow for rapid characterization of diverse nanoparticles, combining UV/Vis deconvolution and DLS sizing in a single step. Its high precision, small sample volume, and automation compatibility address key bottlenecks in nanoparticle research and quality control.

References

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3. Ribeiro L, et al. Use of nanoparticle concentration as a tool to understand the structural properties of colloids. Sci Rep. 2018;8(1):1–8.
4. Hussain M, et al. Comparative analysis of protein quantification methods for liposomal formulations. Pharmaceutics. 2019;11(1).
5. Duong V, et al. Preparation of solid lipid nanoparticles and nanostructured lipid carriers via solvent injection. Molecules. 2020;25(20):4781.