Microfluidic Shear Processing Control of Biological Reduction Stimuli-Responsive Polymer Nanoparticles for Drug Delivery

Abstract

We demonstrate microfluidic manufacturing of glutathione (GSH)-responsive polymer nanoparticles (PNPs) with controlled in vitro pharmacological properties for selective drug delivery. This work leverages previous fundamental work on microfluidic control of the physicochemical properties of GSH-responsive PNPs containing cleavable disulfide groups in two different locations (core and interface, DualM PNPs). In this paper, we employ a two-phase gas–liquid microfluidic reactor for the flow-directed manufacturing of paclitaxel-loaded or DiI-loaded DualM PNPs (PAX-PNPs or DiI-PNPs, where DiI is a fluorescent drug surrogate dye). We find that both PAX-PNPs and DiI-PNPs exhibit similar flow-tunable sizes, morphologies, and internal structures to those previously described for empty DualM PNPs. Fluorescent imaging of DiI-PNP formulations shows that microfluidic manufacturing greatly improves the homogeneity of drug dispersion within the PNP population compared to standard bulk microprecipitation. Encapsulation of PAX in DualM PNPs significantly increases its selectivity to cancerous cells, with various PAX-PNP formulations showing higher cytotoxicity against cancerous MCF-7 cells than against non-cancerous HaCaT cells, in contrast to free PAX, which showed similar cytotoxicity in the two cell lines. In addition, the characterization of DualM PNP formulations formed at various microfluidic flow rates reveals that critical figures of merit for drug delivery functionincluding encapsulation efficiencies, GSH-triggered release rates, rates of cell uptake, cytotoxicities, and selectivity to cancerous cellsexhibit microfluidic flow tunability that mirrors trends in PNP size. These results highlight the potential of two-phase microfluidic manufacturing for controlling both structure and drug delivery function of biological stimuli-responsive nanomedicines toward improved therapeutic outcomes.

Hierarchical Self-Assembly Route to “Polyplex-in-Hydrophobic-Core” Micelles for Gene Delivery

“…The final particles following removal of unencapsulated pDNA are designated PIHC micelles. Recent work from our group has demonstrated significant effects of on-chip shear forces in two-phase microfluidic reactors such as the one applied here (Figure ) on the structure and function of polymer-based materials for nanomedicine materials. − Therefore, we were interested in comparing PIHC micelle samples prepared by the bulk and microfluidic SA2 processes in terms of their encapsulation efficiencies (EE), size distributions, and morphologies.…”

“…Another possibility is that the minor population of larger aggregates forms from excess individual PCL- b -PEG chains that do not coassemble with PCL-pDNA in the SA2 process (Figure B). Based on the predominance of small, low-polydispersity spheres, which are favorable for cell uptake and targeting, in addition to the greater reproducibility of pDNA encapsulation, we selected the microfluidic preparation method for further analysis, including in vitro cell experiments.…”

Microfluidic Nanoparticles for Drug Delivery

“…The versatile HFF device, staggered herringbone micromixer, [105] two-phase gas-liquid microfluidic mixers (Figure 6b), [102,[106][107][108][109][110] automated microfluidic Asia 320 flow reactor, [111] the microfluidic coflow capillary device, [112] and impact-jet micromixers [113] have been developed to prepare the synthetic polymer NPs in recent years.…”

Synthesis of multiple stimuli-responsive degradable block copolymers via facile carbonyl imidazole-induced postpolymerization modification

“…[5][6][7] Acid-labile and disulfide linkages are the most studied cleavable linkages in the construction of SRD-exhibiting nanoassemblies. [8][9][10][11][12][13][14][15][16] High redox potentials caused by the higher concentration of glutathione (GSH) in cancer cells, [17][18][19] as well as acidic pH of tumor tissue and endosomes/lysosomes, 20,21 have been exploited as endogenous triggers to destabilize ABP-based nanoassemblies and thus enhance the release of therapeutic agents. In addition, lightcleavable linkages such as o-nitrobenzyl and coumarin groups allow for the spatial and temporal control of release kinetics.…”