Flight instrumentation for the analyses of extraterrestrial environments must often perform under severely restricted conditions. Often, the detection and identification of a multitude of chemical species is required to fulfill the scientific objectives of the mission. It is therefore important that the analytical instrumentation have universal response. The gas chromatograph-ion mobility spectrometer (GC-IMS) has the potential to provide the sample separation, identification and sensitivity necessary for a successful analysis. However, the IMS has poor sensitivity for the C1-C4 alkanes. The abundance of these molecules at various extraterrestrial sites is often of great importance to exobiologists. This study focuses on optimizing IMS sample ionization mechanisms for the C1-C4 alkanes and other hydrocarbons of interest to exobiology.