The Single-probe was fabricated in accordance with established procedures . A Single-probe comprises three primary components: a nano-electrospray ionization (nano-ESI) emitter, a dual-bore quartz needle, and a fused silica capillary (Figure ). The dual-bore quartz tubing (outer diameter 500 μm; inner diameter 127 μm, sourced from Friedrich & Dimmock, Millville, NJ) was pulled into sharp needles (tip size is ~10 μm) using a laser-based micropipette puller (Sutter P-2000, Sutter Instrument, Novato, CA). The nano-ESI emitter was pulled while heating a fused silica capillary (outer diameter 105 μm; inner diameter 40 μm; Polymicro Technologies, Phoenix, AZ) with a butane micro torch. The assembly of a Single-probe entails inserting the fused silica capillary and nano-ESI emitter into the dual-bore quartz needle. To facilitate experimentation, the Single-probe was affixed to a microscope glass slide using epoxy adhesive. Subsequently, the Single-probe was mounted on an XYZ-stage system, and digital microscope (Shenzhen D&F Co., China) was used to monitor cells during the experiment. The entire setup was coupled with an Orbitrap Exploris 240 mass spectrometer (Thermo Scientific, Waltham, MA, USA) for the analysis of SCMS (Figure ).