(625c) Lipid Exchange Envelope Penetration (LEEP) of Nanoparticles for Plantengineering: A Universal Localization Mechanism

Authors: 
Wong, M. H., Massachusetts Institute of Technnology
Giraldo, J. P., Massachusetts Institute of Technology
Kwak, S., Seoul National University
Son, Y., Massachusetts Institute of Technology
Landry, M., University of California Berkeley
Swan, J., Massachusetts Institute of Technology
Blankschtein, D., Massachusetts Institute of Technology
Strano, M., Massachusetts Institute of Technology
Many important plant functions, such as carbon dioxide reduction or energy generation is carried out within the chloroplast â?? a plant organelle that appears greatly under explored as an engineering material. Here, we examine the subcellular uptake and kinetic trapping of a wide range of nanoparticles for the first time, using the plant chloroplast as a model system, but validated in vivo in living plants. Confocal visible and near-infrared fluorescent microscopy and single particle tracking of gold-cysteine- AF405 (GNP-Cys- AF405), streptavidin-quantum dot (SA-QD), dextran and poly(acrylic acid) nanoceria, and various polymer-wrapped single-walled carbon nanotubes (SWCNTs), including lipid-PEG- SWCNT, chitosan-SWCNT and 30-base (dAdT) sequence of ssDNA (AT)15 wrapped SWCNTs (hereafter referred to as ss(AT)15-SWCNT), are used to demonstrate that particle size and the magnitude, but not the sign, of the zeta potential are key in determining whether a particle is spontaneously and kinetically trapped within the organelle, despite the negative zeta potential of the envelope. We develop a mathematical model of this lipid exchange envelope and penetration (LEEP) mechanism, which agrees well with observations of this size and zeta potential dependence. The theory predicts a critical particle size below which the mechanism fails at all zeta potentials, explaining why nanoparticles are critical for this process. LEEP constitutes a powerful particulate transport and localization mechanism for nanoparticles within the plant system.

Reference: Wong MH, Misra R, Giraldo JP, Kwak SY, Son YW, Landry MP, Swan JW, Blankschtein D, Strano MS. 2016. Lipid Exchange Envelope Penetration (LEEP) of Nanoparticles for Plant Engineering: a Universal Localization Mechanism. Nano lett, 16 (2), pp 1161â??1172