The authors fabricate hydrogel-cored liposomes where a cholesterolβTEGβssDNA / acryditeβssDNA duplex (15 bp, theoretical Tm ~55Β°C) spans the hydrogelβbilayer interface: cholesterol inserts into DOPC, acrydite copolymerizes with PEG-DA/PEG-MA inside the liposome lumen via thermally triggered APS/TEMED polymerization at 40Β°Cβa liposome-core hydrogel method they note had only two prior precedents.
SEC (Sephacryl 200) shows hydrogel-liposomes and surfactant-stripped hydrogels elute identically in the void volume while surfactant-lysed plain liposomes release encapsulated rhodamine; TEM shows ~80 nm hydrogel cores; DNase treatment generates no low-MW H33342 species, implying all dsDNA resides inside the vesicleβconsistent with polar DNA partitioning away from the outer leaflet.
Key stability result: anchored particles released only ~22% of ANTS payload over 184 h in 20% serum (n=3 trials, Β±1 SD shown in paper), while hydrogel-only and plain liposomes achieved 100% release; DLS confirmed anchored particles avoided the serum-induced size growth seen in controlsβan effect attributed to covalent anchoring raising the energy needed for bilayer delamination.
Strengths include internally consistent multi-method characterization (SEC, TEM, DLS, H33342 fluorescence dequenching) and clever controls: above-Tm SEC converts duplexes to ssDNA-nanogels, and DNA-1 titration saturates at ~9 Β΅M with the characteristic H33342 blueshift, confirming ~20 solvent-accessible hybridization sites per nanogelβenabling DNA-programmed assembly.
Limitations: the DLS polydispersity is large (53Β±31 nm stripped nanogels), so the ~20-DNA count carries wide uncertainty; DOPC (fluid-phase) rather than PEGylated/stealth compositions were tested, and serum-stability comparisons to pegylated standards are absent; no in vivo, cytotoxicity, or immunogenicity data exist, so the drug-delivery framing is entirely a prototype claim; encapsulation efficiency for a model peptide was low (8β10%) and unchanged by the hydrogel, leaving cargo-loading advantages unproven. Notably, the paper itself flags these gapsβproposing degradable PEG cores and disulfide crosslinks as future workβso several apparent omissions are acknowledged rather than missed.
Conclusion (moderate confidence): the structural and stability claims are well-supported by convergent in vitro evidence; the biomimetic-cytoskeleton and drug-delivery applications remain extrapolations requiring cell/in vivo testing. Falsification would require showing DNA linkers fail to anchor under physiological shear, or that stability gains vanish in PEGylated formulations or whole serum complement.
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