Polymer Nanocapsules for Drug Delivery Applications

Polymer nanocapsules represent a versatile class of nanoscale carriers characterised by a polymeric shell encapsulating an aqueous or oil-phase core. Their tunable architecture enables precise control over drug loading, release kinetics and surface functionality. By selecting biocompatible and biodegradable polymers—such as poly(lactic-co-glycolic acid) (PLGA), poly(ethylene glycol) (PEG) and cyclodextrin-based amphiphiles—researchers can tailor capsule stability, circulation time and cellular targeting. Surface modifications, for example with polyethyleneimine or peptide ligands, facilitate active uptake into target tissues or cells, enhancing therapeutic index while minimising off-target effects. Advances in polymerisation techniques, including reversible addition–fragmentation chain transfer (RAFT) and atom transfer radical polymerisation (ATRP), have improved control over shell thickness, porosity and degradability. Emerging designs exploit stimuli-responsiveness—pH, redox potential or enzymatic activity—to trigger on-demand drug release in specific physiological environments. Collectively, these innovations hold promise for the treatment of cancer, inflammatory disorders and infectious diseases through enhanced bioavailability, reduced systemic toxicity and the potential for personalised dosage regimens.

Research from Nature Portfolio

Recent studies have explored novel strategies for controlled release and capsule formation. One investigation demonstrated that sodium dodecyl sulfonate can induce the selective disruption of six-layer polyelectrolyte microcapsules, achieving up to 54 per cent release of encapsulated dextran within hours. By varying surfactant concentration, the rate and extent of release can be finely adjusted, offering a platform for sustained or burst delivery profiles. Another foundational study revealed that simple carbohydrate molecules, notably fructose, can direct the self-assembly of hydrophobic curcumin into uniform nanocapsules measuring 100–150 nm. This sugar-mediated process relies on hydrogen-bonding interactions to stabilise curcumin capsules in aqueous media, providing a template for subsequent polymer shell formation and expanding the toolkit for encapsulating poorly soluble drugs.

Polymer Nanocapsules for Drug Delivery Applications publication trend

The graph below shows the total number of articles in polymer nanocapsules for drug delivery applications across all publications each year (not limited to Nature Index journals).

Technical terms

Polymer nanocapsule: A nanoscale particle with a polymeric shell surrounding a liquid core, used to encapsulate and deliver therapeutic agents.

Core–shell structure: A two-layer architecture in which an inner core (liquid or solid) is enveloped by an outer polymer shell.

Redox-responsive: A material property that enables structural change or degradation in response to the oxidising or reducing environment.

RAFT polymerisation: A controlled radical polymerisation technique allowing precise adjustment of polymer chain length and architecture.

Cyclodextrin amphiphile: A cyclic oligosaccharide modified with hydrophobic and hydrophilic segments that self-assemble into vesicular nanostructures.

References

1. PLGA Core-Shell Nano/Microparticle Delivery System for Biomedical Application. Polymers (2021).
2. Controlled Cellular Delivery of Amphiphilic Cargo by Redox‐Responsive Nanocontainers. Advanced Science (2019).
3. Biodegradable and Dual‐Responsive Polypeptide‐Shelled Cyclodextrin‐Containers for Intracellular Delivery of Membrane‐Impermeable Cargo. Advanced Science (2021).
4. Synthesis of polymer-vesicle latex particles through an ATRP-based approach. Colloid and Polymer Science (2022).
5. Destruction of polyelectrolyte microcapsules and release of FITC-dextran from them by the influence of sodium dodecyl sulfonate. Scientific Reports (2022).
6. Just add sugar for carbohydrate induced self-assembly of curcumin. Nature Communications (2019).