In droplet microfluidics high-throughput screening process, toxic product synthesis often inhibits cell growth, reducing screening accuracy.This study established a dynamic regulation method using trans-oil-phase diffusion in droplets to decouple cell growth and product synthesis.Single cells were first encapsulated and cultured within droplets to promote proliferation.Then, the inducer IPTG was encapsulated.The oil-water amphiphilicity of the inducer isopropyl-β-D-thiogalactopyranoside (IPTG) enabled its diffusion across the oil phase into cell-containing droplets for induction.Using Escherichia coli expressing the toxic protein Phi29 DNA polymerase (Phi29 pol) as a model, a Phi29 pol-super-fold green fluorescent protein (sfGFP) fusion reporter was constructed to monitor expression via sfGFP fluorescence intensity.Single-factor optimization identified that a 1∶100 ratio of induction-to-cell droplets with a final IPTG concentration of 1.2 mmol/L achieved the highest Phi29 pol-sfGFP expression level within droplets.This condition achieved a 2.73-fold that of single-cell controls.In general, this system utilized oil-water interfacial diffusion dynamics to minimize growth inhibition caused by toxic product accumulation.It provides a methodological support for high-throughput screening in droplet microfluidics.
HUA Xirui
,
YU Wenwen
,
XU Xianhao
,
WU Yaokang
,
LIU Yanfeng
,
LI Jianghua
,
DU Guocheng
,
LYU Xueqin
. Construction and application of a single-cell dynamic regulation system based on oil-water interface diffusion[J]. Food and Fermentation Industries, 2025
, 51(24)
: 216
-222
.
DOI: 10.13995/j.cnki.11-1802/ts.042689
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