|Fast bioanalysis requires using short columns packed with high efficiency particles. In this work, we demonstrated the ease of converting traditional multi-minute assays run on porous particles to one-minute assays using a 20 or 30 mm fused core column on a standard LC-MS instrument. In addition to faster analysis, chromatographic resolution and peak shape were maintained over the conversion. Better efficiency was obtained using the fused core columns, even though the analysis was run at higher flow rates. System backpressures were maintained at less than 240 bar indicating that standard LC instruments can be routinely used with fused core particles.