“…Vinogradov et al initially introduced the term "NanoGel" in 1999 to describe the particles of a hydrophilic polymer network (PEG-PEI) obtained by crosslinking polyethylene glycol (PEG) (Pappu et al, 2016;Heldt et al, 2019;Kazkayasi et al, 2022) Intrathecal Less invasive Infection, dosedependent drug resistance (Falagas et al, 2007;Jain et al, 2019;Nau et al, 2021;Sari et al, Nanocarriers system Potential toxicity depends on the material used (Bajracharya et al, 2019;de Souza et al, 2020;Wang et al, 2020) and polyethyleneimine (PEI) that were able to deliver antisense oligonucleotides (Zhao et al, 2015). These hydrogel nanoparticles are generally defined as three-dimensional colloidal hydrogel nanoparticles obtained by physical or chemical crosslinking of the polymers with a diameter < 200 nm, thus possessing both the advantages of a hydrogel and characteristics of a nanocarrier system (Goldberg et al, 2007;Zhang et al, 2021a).…”