Molecular electronics, i.e., the measuring of the solid-state electron transport (ETp) across single molecules, is one of the most fascinating endeavors in modern nanotechnology in recent decades. This field is not only aiming to quantify the conductance on the molecular level but also to understand it, which further allows the control or manipulation of the conductance properties. Several organic molecules have been explored for their ability to be integrated into molecular electronic devices, including saturated and conjugated molecules, as well as biological molecules such as DNA and proteins. The topic here concerns the latter, i.e., proteins, whereas our chosen protein for making the molecular junction device is the Human Serum Albumin (HSA) monolayers. What differentiates HSA from any other molecule or even a protein is its extraordinary binding capabilities that can be utilized to control the conductance across it in a process we refer to as molecular doping. Previously, we have shown that doping the HSA with hemin molecules exhibited more than an order of magnitude increase in the measured current density compared to pristine HSA monolayers (J. Am. Chem. Soc. 134, 18221–18224 (2012)). This difference shows that the intramolecular cofactors within the protein have a significant role in the ETp mechanism. Here, we show our capability to manipulate the concentration of different molecular dopants within the HSA protein. We further show that different concentrations of the molecular dopant can change the suggested ETp mechanism across the protein. In the second part of our work, we will switch to another non-biological molecule to be used in molecular junctions, where we explore the conductance across carbon dots (CDs) nanoparticles for the first time. CDs are a relatively new class of carbon nanomaterials of sizes below 10nm, which gained widespread attention in recent years and mainly in the fields of optoelectronics, photosensitizing materials, and bioimaging applications. In our quest of manipulating the ETp properties of a molecular junction, we also explore how the doping of CDs with nonmetal ions can influence their electrical characteristics. We show that the doping of the CDs with nitrogen, phosphorus, and boron can alter the conductance properties across the CDs. However, unlike the conventional phosphorus and boron doping of common semiconductors that influences the charge carrier identity, we show here that such dopants alter the chemical composition of the CDs, which is the reason for the improved conductance upon doping the CDs.