to the embodiment of the present disclosure in order to determine an entire size and surface charge of the prepared particles dynamic light scattering dls was used a size distribution and surface charge of the particles were measured with lasers in a wavelength of 653 nm using a dls device els z series manufactured by otsuka electronics co ltd a size of the particles was measured more precisely using software of the dls device known as a cumulant method here the number of cumulants was limited to 100 or more for use in the case of the particles having a lipid soluble polymer an average particle diameter was determined to be 200 nm or less the results are as shown in fig3 a further the particles having a water soluble polymer were also measured with a dls device and an average particle diameter was determined to be in a range of 300 to 7800 nm depending on an amount of water soluble polymer nucleic acids filled in the particles the results are shown in fig3 b the drug entrapment of the particles was determined through experiments an amount of a drug injected into the particles was calculated by measuring a concentration of a drug remaining in a solution after the particles were formed the drug used herein was largely divided into a nucleic acid dna.