Responsive Polymer/Liposome Complexes: Design, Characterization and Application
Bibliographic record
Abstract
The interactions between vesicles and hydrophobically-modified copolymers of N-isopropylacrylamide (NIPAM) and N-glycine acrylamide (Gly) have been examined by fluorescence spectroscopy, dynamic light scattering, and dye-release studies. Four different polymer samples were employed: a copolymer of NIPAM and Gly (PNIPAM-Gly), a copolymer of NIPAM, Gly, and N-(1-pyrenylmethylacrylamide) (PNIPAM-Gly-Py), a copolymer of NIPAM, Gly, and N-(n-octadecylacrylamide) (PNIPAM-Gly-C 18 ), and a copolymer of NIPAM, Gly, and N-[4-(1-pyrenyl)butyl]-N-n-octadecylacrylamide (PNIPAM-Gly-C 18 Py). The polymers form soluble micelles in cold water but their solutions undergo phase separation upon heating above a critical temperature. In the presence of liposomes the polymeric micelles are disrupted and the hydrophobic substituents of the polymer are incorporated within the liposome bilayer to yield polymer/liposome complexes. The binding of PNIPAM-Gly-C 18 Py with liposomes was assessed as a function of the chemical composition of the liposome membrane, the total lipid concentration, and the incubation time. Three factors control the polymer/liposome interactions: (1) hydrophobic interactions driven by the nonpolar side groups of the polymer; (2) hydrogen-bond formation between the amide residues of the NIPAM units and the ethylene glycol head groups of the lipid; and (3) hydrogen-bond formation between the Gly residues of the polymer and those linked to the liposome bilayer via incorporation in the bilayer of the glycine-terminated lipid, 1',3'-dihexadecyl N-[1-(N-glycyl)succinyl]-L-glutamate ((C 16 ) 2 -Glu-C 2 -Gly). The latter interactions are labile and can be disrupted by changes in pH. Thus, efficient release of calcein took place when a pH 7.4 suspension of calcein-loaded liposomes containing (C 16 ) 2 -Glu-C 2 -Gly in their bilayer and coated with PNIPAM-Gly-C 18 Py was acidified to pH 6.0.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".