To evaluate the behavior of the system upon temperature changes during the adsorption process, 1 mL volume of AgNPs suspension was thermostated at a designated temperature of 55 °C and a 10 µL aliquot of the Cys-cabn isotopologue 0.5 mM solution was initially added to the suspension. Subsequently, the suspension was cooled down to 40 °C after 1 or 5 minutes from the beginning of Cys-cabn adsorption. 10 µL aliquot of Cys-CABN was added after 10 minutes from the beginning of Cys-cabn adsorption, already at a stable temperature of 40 °C. The stirring continued until 30 minutes passed since the first Cys-cabn aliquot was introduced, when the SERS response was collected.