Chemical processes taking place during the early protostellar phases strongly affect the final chemical composition of a forming planetary system. While close to the protostar a chemical reset is expected, in the outer protostellar disk a consistent part of the molecular complexity is expected to be inherited from the early stages. The vast majority of the observations dedicated to explore the chemical variety of solar-type protostars has been obtained via (sub-)millimeter telescopes, where several relatively light molecules, such as interstellar complex organic molecules (iCOMs) or the small carbon chains have their peak of emission. In contrast, lines of heavy molecules (e.g. chains and rings with more than seven C-atoms) at mm wavelengths are substantially weaker. Their observation could add an important piece of the overall puzzle as they might have a crucial role in the heritage of organic material from the pre- and proto- stellar phase to the objects of the newly formed planetary system, like asteroids and comets (e.g. Mumma & Charnley 2011, McGuire et al. 2019).
We will report the results obtained in a pilot study proposed using the 100m Green Bank Telescope to observe several crucial carbon chains in the 8.0 ? 11.5 GHz and 14.0?15.4 GHz intervals, in L1544 and IRAS16293-2422, which are the two archetypes of prestellar cores and protostars, respectively. GBT observations, covering part of the frequency range of the future SKA1-MID, reveal richness of C-chains (e.g. C4H, C6H, HC7N, HC9N, C3S) and a chemical differentiation between the two sources at large angular scales (Bianchi et al. 2023). These preliminary results stress the importance of SKA observations to image the spatial distribution of the observed carbon chains and to understand if large carbon chains and iCOMs coexist in the planets formation region.