# Evidence: local equilibrium

Parent: — · class: thermodynamics · names merged here: local equilibrium

3 papers measured or used it, 0 only mentioned it (of 207 kept papers). Papers in year order; each section heading ends with the paper's category / subcategory. Generated by tools/build_evidence.py from registry/concepts.csv and the cards; do not edit.

## 2023 Deac — Dissolution Mechanisms of Amorphous Solid Dispersions: A Close Look at the Dissolution Interface · Dissolution / A. Release mechanism and LoC

[2023-deac-asd-dissolution-interface](../../../cards/2023-deac-asd-dissolution-interface/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: local equilibrium

| id | kind | content | locator |
|---|---|---|---|
| C39 | claim, conclusion, authors: "suggesting"; "Indeed" | The released hydrophobic phases resemble the equilibrated hydrophobic phases of the previous study (R18), suggesting their Tg is low enough to reach compositional equilibrium within the experiment; both Tgs are below 37 °C [rests on: R12, R18] | p.2226 |
| C70 | claim, assumption, authors: "may be valid"; "may conform" | The framework assumes phase separation fast enough to give near-equilibrium phase compositions along the hydration path, which may hold if the hydrophobic phase is mobile; with hydrophobic-phase Tg below 37 °C the systems here may conform; the behaviour of high-Tg hydrophobic phases needs further work [rests on: R12, C39] | p.2232 |

## 2023 Deac — Dissolution Mechanisms of Amorphous Solid Dispersions: Role of Drug Load and Molecular Interactions · Dissolution / A. Release mechanism and LoC

[2023-deac-asd-drug-load-molecular-interactions-loc](../../../cards/2023-deac-asd-drug-load-molecular-interactions-loc/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: local equilibrium

| id | kind | content | locator |
|---|---|---|---|
| C38 | claim, assumption, authors: "some supporting evidence to suggest"; "may adhere" | The two phases reach equilibrium as fast as or faster than water penetrates, so the phases across the gel layer are in pseudoequilibrium with the local water content; PHPH and MePHPH systems may comply, since nanoparticles equilibrated in less than 5 min and compact surfaces above the LoC reached pseudo-equilibrium in less than 10 min [rests on: R2, R6, R7] | p.731-732 |
| C61 | claim, mechanism, authors: "it is possible" | The gel-layer surface can equilibrate with the solution (water activity near unity) and so resemble the dilute nanoparticle composition, while deeper layers with less water access other regions of the diagram; the surface composition is a pseudo-equilibrium with the dilute aqueous environment [rests on: R6, R7, R3] | p.734 |
| C3 | claim, conclusion, authors: asserted ("It was found") | ASD compacts with drug loads above the LoC formed an insoluble surface barrier that was in pseudo-equilibrium with the aqueous phase and prevented further release of drug and polymer during dissolution [rests on: R6, R7] | p.722 |

## 2024 Deac — Dissolution Mechanisms of Amorphous Solid Dispersions: Application of Ternary Phase Diagrams To Explain Release Behavior · Dissolution / A. Release mechanism and LoC

[2024-deac-asd-ternary-phase-diagrams-release](../../../cards/2024-deac-asd-ternary-phase-diagrams-release/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: local equilibrium

| id | kind | content | locator |
|---|---|---|---|
| C48 | claim, assumption, authors: asserted; "it is assumed" | ASD hydration is represented as a straight path at constant drug:polymer ratio toward the water vertex (polymer kinetically trapped in the gel layer; drug with minimal driving force to enter solution, as in congruent release); fast water ingress carries the composition across the binodal to the spinodal, where phase separation proceeds by spinodal decomposition; phase compositions then follow the binodal in local equilibrium with the local water content [rests on: argument only] | p.1913-1914 |
| C49 | claim, mechanism, authors: asserted | The kinetic lag before phases equilibrate with the local water content depends on molecular mobility; high mobility shortens it [rests on: argument only] | p.1914 |
| C50 | claim, conclusion, authors: "likely"; "also suggests" | MePHPH- and PHPH-PVPVA ASDs likely comply with the rapid (local) equilibration assumption, given the low Tg of the phases and the close match of predicted Wα with film observations [rests on: R29, R30, R35] | p.1914, p.1915 |
| C54 | claim, generalisation, authors: "may" | ASDs with high-Tg drugs may not conform to the local-equilibrium assumption and may show a different effect on release [rests on: cited: refs 21, 53] | p.1915 |