Serum Protects Cells and Increases Intracellular Delivery of Molecules by Nanoparticle-Mediated Photoporation

Abstract

Simple Kumar,1 Eunice Lazau,2 Carter Kim,2 Naresh N Thadhani,3 Mark R Prausnitz1 1School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA; 2School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA, 30318, USA; 3School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USACorrespondence: Mark R PrausnitzFord Environmental Science & Technology Building, 311 Ferst Drive NW, Atlanta, GA, 30332, USATel [phone]Fax [phone]Email [email protected]: Intracellular delivery of molecules is central to applications in biotechnology, medicine, and basic research. Nanoparticle-mediated photoporation using carbon black nanoparticles exposed to pulsed, near-infrared laser irradiation offers a physical route to create transient cell membrane pores, enabling intracellular delivery. However, nanoparticle-mediated photoporation, like other physical intracellular delivery technologies, necessitates a trade-off between achieving efficient uptake of exogenous molecules and maintaining high cell viability.Methods: In this study, we sought to shift this balance by adding serum to cells during nanoparticle-mediated photoporation as a viability protectant. DU-145 prostate cancer cells and human dermal fibroblasts were exposed to laser irradiation in the presence of carbon black (CB) nanoparticles and other formulation additives, including fetal bovine serum (FBS) and polymers.Results: Our studies showed that FBS can protect cells from viability loss, even at high-fluence laser irradiation conditions that lead to high levels of intracellular delivery in two different mammalian cell types. Further studies revealed that full FBS was not needed: viability protection was achieved with denatured FBS, with just the high molecular weight fraction of FBS (> 30 kDa), or even with individual proteins like albumin or hemoglobin. Finally, we found that viability protection was also obtained using certain neutral water-soluble polymers, including Pluronic F127, polyvinylpyrrolidone, poly(2-ethyl-2-oxazoline), and polyethylene glycol, which were more effective at increased concentration, molecular weight, or hydrophobicity.Conclusion: Altogether, these findings suggest an interaction between amphiphilic domains of polymers with the cell membrane to help cells maintain viability, possibly by facilitating transmembrane pore closure. In this way, serum components or synthetic polymers can be used to increase intracellular delivery by nanoparticle-mediated photoporation while maintaining high cell viability.Keywords: drug delivery, carbon black nanoparticle, photoporation, polymer, cell viability

Keywords

• drug delivery
• carbon black nanoparticle
• photoporation
• polymer
• cell viability