To provide insights on the molecular growth mechanisms leading to large carbon and nitrogen-bearing species in Titan’s ionosphere, laboratory measurements of ion-neutral reactions were conducted and the results are presented in the following doctoral dissertation. The product ions of the C₂H₂N⁺ reactions with saturated and unsaturated neutral hydrocarbons have been investigated using Guided Ion Beam Mass Spectrometer (GIB-MS). The data have been used to reveal the dependence of product ion intensity on pressure and also with respect to collision energy variations to derive useful insights on the nature of chemical reactions leading to the observed species. Complementary theoretical calculations have been also carried out to assist in interpretation of these measurements and to elucidate the reaction schemes. This study provides comprehensive insights on the formation of long chain and heavy carbon-nitrogen bearing species through exothermic and barrierless ion-neutral reactions which are likely to play a significant role in the formation routes of heavy positive ions of interest, which have been detected in Titan’s ionosphere by Cassini’s Ion Neutral Mass Spectrometer (INMS).