# Evidence: glass-gel interface

Parent: — · class: transport and absorption · names merged here: glass-gel boundary; glass-gel interface

2 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.

## 2022 Yang — Release mechanisms of amorphous solid dispersions: Role of drug-polymer phase separation and morphology · Dissolution / A. Release mechanism and LoC

[2022-yang-release-mechanisms-rtv-pvpva-asd-phase-separation-morphology](../../../cards/2022-yang-release-mechanisms-rtv-pvpva-asd-phase-separation-morphology/paper.html) · Dissolution / A. Release mechanism and LoC · measured · as: glass-gel interface

| id | kind | content | locator |
|---|---|---|---|
| R8 | record, measured | depth penetrated by the gel-glassy interface, % of initial compact thickness (mean ± SD, n = 3) — P10; neat PVPVA and 10-40% DL compacts in P2 — sub-table below; text: same rate for neat PVPVA, 10 and 20% DL, about half the compact penetrated after 10 min and the entire compact after 20 min; slower at 30 and 40% DL with a plateau after 20 min | Fig. 6, pdf p.14; text pdf p.13-14 |
| R9 | record, measured | time-lapse morphology, neat PVPVA compact (scale bars 100 µm) — P7; images at 0, 1, 2, 5, 10, 15 min — before medium: homogeneous orange; black area on the right = slide/air interface; at 1 min the compact longer than before; later the compact decreases in size; an orange-green boundary (dotted line) separates an unchanged orange dry compact (left) from a green gel layer (right); green fades from left to right; no red in the bulk solution; the boundary moves deeper into the matrix from 1 to 15 min; gel layer homogeneous | Fig. 7, pdf p.16; text pdf p.14-15 |
| C28 | claim, assumption, authors: asserted | Movement of the gel-glass interface indicates how fast water penetrates the ASD matrix [rests on: argument only] | pdf p.13 |
| C29 | claim, conclusion, authors: "suggests" | Below the LoC water penetration is not affected by the drug or retarded by drug-rich domains (same rate as neat PVPVA at 10 and 20% DL); above the LoC penetration becomes slower with increasing DL [rests on: R8] | pdf p.13 |

## 2024 Deac — Dissolution mechanisms of amorphous solid dispersions: Role of polymer molecular weight and identification of a new failure mode · Dissolution / A. Release mechanism and LoC

[2024-deac-asd-polymer-molecular-weight-failure-mode-loc](../../../cards/2024-deac-asd-polymer-molecular-weight-failure-mode-loc/paper.html) · Dissolution / A. Release mechanism and LoC · used · as: glass-gel boundary

| id | kind | content | locator |
|---|---|---|---|
| C31 | claim, mechanism, authors: asserted | In the congruent regime release is dictated by the polymer, so clotrimazole release from congruent PVP ASDs resembles neat PVP release; the ASD releases like a neat glassy polymer: water penetration turns the glass into a viscous rubbery gel layer, concentration and viscosity gradients develop across the gel layer and the solution boundary layer (Fig. S7), and at the gel-solution boundary the viscosity is low enough for polymer chains, together with trapped droplets and solutes such as dye, to release [rests on: R1, R3; cited: refs 8, 21, 27, 41] | p.8 |
| C32 | claim, conclusion, authors: asserted | The glass-gel boundary is the sharp colour transition between regions 1 and 2 of Fig. 5, and the gel-solution boundary is where red fluorescence drops to background between regions 2 and 3 [rests on: R10] | p.8 |