Renewable Nanomedicines Require Rigorous Performance Metrics Beyond Natural Origin Alone

Nanomedicine is redefining pharmaceutical delivery and diagnostic bioimaging by engineering nanoscale materials with size-dependent physicochemical properties that alter biodistribution and therapeutic indices. According to definitions established by the European Medicines Agency, nanomedicines encompass medicinal products containing at least one nanoscale component that imparts definable clinical advantages, such as preferential tissue distribution, whereas the United States Food and Drug Administration encompasses fabricated medical systems with structural dimensions up to 1000 nanometers. Over three decades since the 1995 approval of liposomal doxorubicin, clinical translation has advanced to modern nanotechnology-enabled interventions, including the 2023 approval of the respiratory syncytial virus vaccine Arexvy and the 2024 debut of the lipid nanoparticle platform mRESVIA. Amid broader industrial shifts away from fossil-based resources, renewable biomass that replenishes faster than its depletion under ISO 14021 standards has gained substantial attention as feedstocks for nanocarriers. However, renewable origin alone does not ensure clinical readiness or environmental sustainability, as sustainable materials must strictly minimize ecological burdens across their entire life cycle without disrupting ecological equilibria.

Synthetic aliphatic polyesters derived from renewable monomers, particularly lactide and lactones, establish benchmark control over nanocarrier architecture, degradation rates, and payload interactions. Amorphous poly(D, L-lactic acid) degrades significantly faster than stereoregular crystalline poly(lactic acid), providing adaptable platforms for controlled release. Compared to naturally isolated macromolecules that suffer from batch variations, lactide and lactone polymers allow precise synthetic tuning of block lengths, molecular weights, and end-group functionalities via controlled ring-opening polymerization. In therapeutic applications, poly(jasmine lactone) conjugated to doxorubicin and docetaxel through reactive oxygen species-cleavable thioketal linkers, combined with chlorin e6, produced potent near-infrared light-triggered cell killing in Vero H10 cultures.

Naturally occurring polysaccharides harvested from marine organisms, microbial cultures, plants, and animal tissues present distinct biochemical advantages through intrinsic cell-surface recognition and mucosal adhesion. Abundant pendant hydroxyl, amino, and carboxyl groups facilitate chemical derivatization and functional crosslinking without requiring complete de novo polymer backbone assembly. Dual-targeting chitosan nanoparticles modified with cetuximab and sialic acid achieved superior cellular uptake and tumor suppression in A549 lung cancer cells and benzo[a]pyrene-induced murine lung tumors when delivering gemcitabine. Nevertheless, polysaccharides exhibit marked structural heterogeneity, where fluctuating branching patterns, degrees of substitution, and source purities alter formulation viscosity, charge density, and particle diameter. Furthermore, the inherently hydrophilic polysaccharide backbone impedes high loading efficiencies for hydrophobic drugs, necessitating chemical grafting or lipid combinations that complicate downstream characterization and potentially alter the polymer biodegradation profile.

Protein and polypeptide nanocarriers leverage specific genetically encoded amino acid sequences and defined three-dimensional folds to achieve exceptional target avidity and programmed metabolic clearance into endogenous amino acids. The maturation of recombinant DNA technology has bypassed historic dependencies on tissue-extracted biological materials, enabling sequence-tailored human recombinant soluble proteins, such as angiotensin-converting enzyme 2 manufactured during the COVID-19 pandemic. In nanocarrier formulations, bovine serum albumin nanoparticles co-loaded with all-trans retinoic acid and curcumin enhanced glioblastoma cell apoptosis to 37.6 percent in U87-MG lines, markedly surpassing single-agent controls.

Lipid-based systems represent the most clinically mature nanomedicine platform, offering superior biological barrier traversal, membrane compatibility, and payload protection. Preclinical studies illustrate that doxorubicin-loaded phosphatidylcholine and cholesterol nanoparticles enhanced in vitro cytotoxicity 1.8-fold and cellular internalization 2.3-fold in MCF-7 breast cancer lines while producing a 1.3-fold increase in tumor inhibition in vivo alongside attenuated cardiotoxicity and nephrotoxicity. However, widespread clinical use of lipid nanoparticles for nucleic acid delivery cannot be conflated with the validation of entirely renewable nanomedicines. True lifecycle sustainability claims therefore require accounting for the synthetic fossil-derived proportions of functional formulation excipients rather than focusing solely on the natural origin of primary lipid matrix components.

In nucleic acid and vaccine delivery, non-viral renewable and hybrid carriers offer alternatives to viral vectors that are constrained by immunogenicity, restricted packaging capacities, and expensive manufacturing. Plant-derived tobacco mosaic virus coat proteins engineered into virus-like particles containing self-amplifying Nodamura replicon mRNA elicited ten-fold higher replication than free Omicron receptor-binding domain constructs and induced a 1.5-fold increase in immunoglobulin G antibody titers in vivo. In pest management, rosin-modified polyethylene glycol and chitosan complexes delivering double-stranded RNA against brown planthoppers suppressed chitin synthetase A expression by 54.3 percent and reduced rat mortality by 65.8 percent. For human therapeutics, hybrid delivery platforms combining mesenchymal stem cells with poly(lactic-co-glycolic acid) achieved 67.3 percent transfection of hypoxia-inducible factor-1α small interfering RNA in carrier cells and reduced target messenger RNA expression by 40 percent in retinal pigment epithelial cells, with transfection efficiencies rising to 72.7 percent upon adding cationic lipids.

Renewable carriers significantly improve antimicrobial and antiviral therapeutics by elevating local drug retention, enhancing bioavailability, and mitigating toxicities associated with conventional treatment regimens. In oral antifungal applications, lipid-polymer hybrid nanoparticles constructed from poly(δ-decalactone) achieved a 19.5 percent posaconazole loading, while GastroPlus physiological modeling predicted a 2.06-fold increase in maximum plasma concentration over unformulated drug suspensions. For viral infections, a niclosamide-magnesium oxide-hydroxypropyl methylcellulose nanohybrid increased niclosamide oral bioavailability four-fold, suppressed SARS-CoV-2 replication in Syrian hamsters, and reduced viral loads by 56.7 percent within sixteen hours in a double-blind clinical trial of 300 COVID-19 patients, demonstrating verified safety without adverse biochemical or histopathological alterations across thirteen weeks of evaluation.

Biomedical imaging modalities increasingly integrate renewable materials as stabilizing coatings, targeting matrices, and biocompatible shells, although the renewable polymers themselves rarely generate the primary imaging contrast. Diagnostic signals instead originate from inorganic crystals, magnetic cores, or synthetic fluorophores, designating these systems as renewable-inorganic hybrid platforms rather than fully renewable imaging agents. Growing silver sulfide quantum dots onto cellulose nanocrystals functionalized with folic acid and polyethylene glycol yielded probes displaying intense near-infrared fluorescence and enhanced intracellular uptake. In magnetic resonance imaging, coating zinc ferrite nanoparticles with bovine serum albumin decreased saturation magnetization from 71 to 54 electromagnetic units per gram while suppressing particle aggregation, yielding transverse relaxivity values of 133 inverse millimolar-seconds and a relaxivity ratio of 16.2 at 1 Tesla.

Translating renewable nanomedicines from academic laboratories to industrial production encounters severe technical bottlenecks spanning raw material variability, process scalability, physiological stability, and regulatory ambiguity. Furthermore, physiological exposure threatens colloidal integrity, exemplified by poly(lactic-co-glycolic acid) carriers undergoing pH-dependent swelling, aggregation, and enzymatic ester cleavage in simulated gastrointestinal fluids. Complicating these physical hurdles, regulatory assessments by the FDA, EMA, and PMDA continue on disparate, case-by-case bases due to a lack of harmonized nanotherapeutic evaluation frameworks.

Bridging these persistent translational gaps requires moving beyond empirical laboratory formulation toward predictive computational workflows and rigorous lifecycle environmental assessments. Concurrently, genuine sustainability assessments must quantify comprehensive lifecycle metrics, including industrial solvent toxicity, operational energy consumption, and process waste generation, rather than presuming environmental safety solely from natural feedstock origin. Ultimately, establishing renewable nanomedicines as viable clinical realities requires integrating reproducible continuous synthesis, verified biological clearance kinetics, harmonized regulatory standards, and predictive formulation modeling from early discovery stages.

Subject of Research: Evaluation of renewable material nanomedicines for therapeutic delivery and biomedical imaging

Article Title: Nanomedicines based on renewable materials for sustainable drug delivery and biomedical imaging applications

Article References: Kumar, V., Zaman, M. M. U., Wilén, C.-E., Rosenholm, J. M., & Bansal, K. K. (2026). Nanomedicines based on renewable materials for sustainable drug delivery and biomedical imaging applications. Discover Nano, 21(1), Article 538. https://doi.org/10.1186/s11671-026-04996-7

Image Credits: AI Generated

DOI: 10.1186/s11671-026-04996-7

Keywords: nanomedicine, renewable materials, drug delivery, biomedical imaging, polysaccharides, polyesters, lipid nanoparticles, protein carriers, biodegradability, formulation scalability, translational medicine, cancer nanomedicine, gene delivery, magnetic resonance imaging, biocompatibility, regulatory science