After graduating, Smolková-Keulemansová joined the Faculty of Sciences at Charles University and focused on analytical chemistry. In the early 1950s, she built a team focused on modern analytical separation methods such as gas chromatography, high-performance liquid chromatography and electromigration. At this same time, she attended an analytical conference in Prague, leading to her finding a volumetric chromatographic device. Her team began to prepare its own device with volumetric detection, and constructed a more universal glass thermal conductivity detector, allowing them to analyze a larger variety of gas. Little did she know that this was a new idea and, soon after, this detector became part of a commercially available instrument. Because of her innovation and dedication to the field, people started telling her that she was "the first lady of chromatography".