Acquisition of an asymmetric field flow fractionation-multiangle light scattering (AF4-MALS) system - Project Summary We seek NIH support for the acquisition of an Asymmetric Flow Field-Flow Fractionation system coupled with Multi-Angle Light Scattering (AF4-MALS) to be housed in the Johnson Foundation Structural Biology and Biophysics Core (JFBSB Core) at the University of Pennsylvania. This platform will provide critical capabilities for the separation and label-free analysis of macromolecules and nanoparticles in solution, including lipid nanoparticles (LNPs), viral vectors (e.g., AAVs), protein-nucleic acid complexes, and phase- separated assemblies. The requested commercial instrument integrates two powerful technologies: 1. field- flow fractionation (AF4) for size-based, non-destructive separation of complex or fragile species and 2. multi- angle light scattering (MALS) for the direct measurement of molar mass, radius of gyration, hydrodynamic radius, and particle size distribution without reliance on calibration standards. Additional detectors, including differential refractive index (dRI), dynamic light scattering (QELS), and ultraviolet-visible absorbance, allow the system to rigorously quantify particle concentration, heterogeneity, and conjugation state in real time. These capabilities are essential for fully understanding the structure-function relationships of therapeutic macromolecular formulations and advancing gene delivery technologies. The proposed system will support the work of 10 NIH-funded projects in structural biology and nanomedicine. Projects will include structural optimization of LNP formulations for nucleic acid delivery, analysis of biologically relevant higher-order protein assemblies and aggregates, and separation of nucleoprotein complexes. This technology complements and enhances existing SEC-MALS, SAXS, and AUC platforms at Penn, enabling orthogonal workflows across the campus research landscape. No equivalent system currently exists at the University of Pennsylvania. The requested AF4-MALS system from Wyatt Technology offers unmatched integration with ASTRA software for advanced analysis, U.S.-based support, trade-in options for legacy systems, and the lowest risk of import-related tariff costs among evaluated vendors. The JFBSB Core, with a strong track record of S10 stewardship, will ensure broad access, expert support, and long-term sustainability. The requested instrumentation will have immediate and wide-ranging impact on federally funded research programs across Penn and its affiliated institutions.
