Complex Stimuli Induced by Surface Discharge Method Enable Minimally Invasive and High‐Efficiency Macromolecule Delivery Into Chlamydomonas reinhardtii

Intracellular delivery of macromolecules into microalgae has been constrained by rigid cell walls. This study presents a high‐efficiency, high‐viability method for delivering macromolecules into Chlamydomonas reinhardtii using surface discharge plasma. At a nominal voltage of 25 kV, which produced a favorable balance between delivery efficiency and cell viability, the method achieved > 40% efficiency for 250 kDa FITC‐dextran while maintaining > 80% viability. Under the same conditions, 2 MDa FITC‐dextran was also delivered. Orthogonal cross‐sectional analysis confirmed intracellular cargo localization. Delivery results from cellular responses to plasma‐induced complex stimuli; the ~60% reduction highlights endocytosis as a major pathway, whereas the remaining fraction may involve multifaceted processes such as transient membrane permeabilization. This integrated approach enables minimally invasive macromolecule entry into microalgae.