The ideal nanocarrier can be sustained in the human body for a longer circulation time to deliver the therapeutics with minimum or no side effects. The observed non-target effects can be reduced by passive targeting (Kitayama et al.
2022) or antibody-mediated active targeting of diseased tissue or organs (Li and Qi
2021). Tagging the nanocarrier with ligands and cell-penetrating peptides may facilitate their intracellular delivery (Khalil and Harashima
2023; Liu et al.
2022). Thus, nanogels are tunable and can be functionalized to make them transmigrate across physiological barriers (Zhao et al.
2021) such as gut barrier (Lee et al.
2020), blood–brain barrier (Ribovski et al.
2021), corneal epithelial barrier (Lin et al.
2021), and skin barrier (Cuggino et al.
2019). Smart nanogel may be designed with a capacity to circulate for longer intervals with sustained release, and droplet-based microfluidic development of nanogels for controlled drug delivery can be used to achieve efficiency. Using fluorescent probes and dyes in nanocarriers for imaging purposes bears severe limitations, such as experimental artifacts, toxicity, rapid clearance, photobleaching, and low specificity. In this regard, our nanogel technology has organic biopolymers with the least toxicity and more accuracy with detectable sensitivity. There is a wide range of applications for nanogels ranging from diagnostics to therapeutics. The developed nanogels can be deployed to deliver various biologics, nucleic acids, drugs, and RNA/DNA for the treatment of brain tumors and other carcinomas in the human body, in addition to HIV therapeutics. The existing imaging technologies, such as CT, MRI, PET, and FMT, have their strength and limitations (Lim et al.
2015). The advancements in nanomaterials used for theranostics include nanofillers like CNT, graphene, superparamagnetic nanoparticles, and Au nanoparticles that enhance MRI contrast. Thus, nanogels enable superior imaging with improved diagnostic efficacy. The other important parameter for nanogel-based therapeutics is to optimize the PK and PD properties of drugs loaded inside the nanogel. Thus, clinical translation is still a big challenge. Yet, the advancement in nanogel technology and research team collaborations from multidisciplinary areas may prove to be instrumental in developing a new class of nanogels for clinical use.