An apparatus (10) for coupling liquid chromatography with mass spectrometry and for splitting and analyzing a liquid sample includes a fluid conduit (16), which defines a flow passage (18) and is configured to supply the liquid sample. The fluid conduit (16) has an outer surface and a micro-hole (30) through the outer surface into the flow passage (18). The apparatus (10) also includes an ambient ionizer (40) configured to generate and direct a charged solvent (44) toward the micro-hole (30) at the outer surface for ionizing a portion of the liquid sample (32) that emerges out of the micro-hole (30). The apparatus (10) further includes a mass spectrometer (60) having a sample entrance (62) adjacent the micro-hole (30) configured to analyze an ionized portion of the liquid sample (54).