Table 2 The potential types of nanosystems for microenvironment-responsive applications

Stimuli-responsive NPs

NPs designed to release therapeutic agents in response to specific physiological triggers

pH, redox conditions, enzymes

Targeted drug delivery and controlled release

[61,62,63]

Polymeric NPs

Biodegradable and biocompatible NPs made from polymers that can encapsulate drugs, proteins, or nucleic acids

pH, temperature, enzymes

Drug delivery, gene therapy, protein delivery

[64, 65]

Lipid-based NPs

Nanoparticles composed of lipids that can form vesicles, micelles, or solid lipid NPs, ideal for encapsulating hydrophobic and hydrophilic drugs

Enzymes, pH, temperature

Drug delivery, gene therapy, vaccination

[45, 66]

Inorganic NPs

NPs made from metals, metal oxides, or other inorganic materials, often used for their unique optical, magnetic, or electrical properties

pH, redox conditions, enzymes

Imaging, photothermal therapy, drug delivery

[67, 68]

Hybrid NPs

Combination of organic and inorganic materials to leverage the advantages of both, providing multifunctional capabilities

pH, redox conditions, enzymes

Imaging, drug delivery, photothermal therapy

[69, 70]

Dendrimers

Highly branched, tree-like macromolecules with multiple functional end groups, capable of encapsulating or conjugating various therapeutic agents

pH, enzymes, redox

Drug delivery, gene therapy, diagnostic imaging

[71]

Micelles

Amphiphilic molecules that self-assemble into spherical structures in aqueous environments, suitable for encapsulating hydrophobic drugs

pH, enzymes, temperature

Drug delivery, cancer therapy, diagnostic imaging

[72, 73]

Nanogels

Hydrogel nanoparticles that can swell and shrink in response to environmental conditions, allowing the controlled release of encapsulated drugs

pH, temperature, enzymes, redox

Drug delivery, gene therapy, tissue engineering

[74,75,76]

Carbon-based NPs

Nanoparticles composed of carbon materials like graphene, carbon nanotubes, and fullerenes, known for their high surface area and facile functionalization

pH, redox conditions, temperature

Drug delivery, imaging, photothermal therapy

[77, 78]

Exosomes

Naturally occurring extracellular vesicles that can be engineered to carry therapeutic agents, benefiting from inherent biocompatibility and targeting capabilities

Biochemical signals from target cells

Drug delivery, gene therapy, regenerative medicine

[41, 79]