<p>Abstract—The absorption and luminescence properties of carbon dots based on methacrylate and ethylenediaminetetraacetic acid are considered. The existence of several types of electromagnetic interaction sites is shown. The variation of luminescence spectra with the excitation wavelength is explained. The dependences of the luminescence on the pH, the ionic strength, and the chemical nature of the substance responsible for the required environmental conditions are considered. Strong changes in the carbon dot surface in highly acidic solutions are revealed. The effect of silver nanoparticles on the luminescence properties of carbon dots is discussed. The temporal stability of aqueous solutions of carbon dots is described.</p>