# Evidence: kinetic trapping

Parent: — · class: phase behaviour · names merged here: kinetic trapping

6 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.

## 2009 Rumondor — Phase Behavior of Poly(vinylpyrrolidone) Containing Amorphous Solid Dispersions in the Presence of Moisture · Solid state stability / Physical stability

[2009-rumondor-pvp-asd-moisture-induced-immiscibility](../../../cards/2009-rumondor-pvp-asd-moisture-induced-immiscibility/paper.html) · Solid state stability / Physical stability · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C36 | claim, mechanism, authors: conditional ("If ... was purely a kinetic phenomenon") | In a purely kinetic route the dry drug-PVP glass is a kinetically trapped one-phase mixture that water plasticizes enough to separate; this implies the dry binaries are not thermodynamically miscible at room temperature [rests on: argument only] | p.1502, p.1503 |

## 2015 Purohit — Miscibility of Itraconazole-Hydroxypropyl Methylcellulose Blends- Insights with High Resolution Analytical Methodologies · Solid state stability / Miscibility and drug-polymer interactions

[2015-purohit-itraconazole-hpmc-miscibility-high-resolution-methods](../../../cards/2015-purohit-itraconazole-hpmc-miscibility-high-resolution-methods/paper.html) · Solid state stability / Miscibility and drug-polymer interactions · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C46 | claim, mechanism, authors: "would be expected to persist"; "would reduce" | After solvent removal the domains are glassy at room temperature (Tg 60 and 140 °C), so the system is kinetically trapped: even with favourable mixing thermodynamics, mixing at room temperature is very slow, and heating above Tg lets the system move to the miscible state [rests on: argument only; M1, M2] | p.17 |
| C47 | claim, mechanism, authors: "An alternative explanation"; "very likely trap" | Alternatively ITZ and HPMC have limited miscibility at room temperature that increases with temperature (UCST behaviour): near the drug melting point mixing is favoured by entropy and mobility, and on cooling the glassy blend is trapped in a miscible state [rests on: argument only; cited: ref 77] | p.17 |

## 2016 Li — Nanoscale Infrared, Thermal, and Mechanical Characterization of Telaprevir-Polymer Miscibility in Amorphous Solid Dispersions Prepared by Solvent Evaporation · Solid state stability / Miscibility and drug-polymer interactions

[2016-li-telaprevir-polymer-miscibility-nanoscale-afm-ir](../../../cards/2016-li-telaprevir-polymer-miscibility-nanoscale-afm-ir/paper.html) · Solid state stability / Miscibility and drug-polymer interactions · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C21 | claim, mechanism, authors: "might suggest"; "One explanation might be"; "A more likely explanation"; "may be a result" | The apparent TPV enrichment of the dispersed phase with DL is more likely an artefact of spectral mixing, which falls as domains grow laterally and in height, than a non-equilibrium, kinetically trapped composition [rests on: R12, R6] | p.17 |

## 2017 Li — Understanding the impact of water on the miscibility and microstructure of amorphous solid dispersions – An AFM/LCR and TEM/EDX study · ASD process / ASD process

[2017-li-water-miscibility-microstructure-asd-afm-tem-edx](../../../cards/2017-li-water-miscibility-microstructure-asd-afm-tem-edx/paper.html) · ASD process / ASD process · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C38 | claim, mechanism, authors: asserted | On the ECP-methanol-water diagram (Fig. 12A, phase boundaries only, kinetics not considered) trace water moves the system from A to B (still miscible); spin coating carries it along B to D, crossing the binodal at C; water spiking moves it along A-B-E with separation at E; at D all water has gone but drug droplets stay kinetically trapped for lack of mobility; less water is needed along BCD than along BE [rests on: R16, R14, R15] | p.34-35 |
| C43 | claim, caveat, authors: "may be"; "we think that this scenario is less likely" | The observed "miscibility" may instead be a kinetically trapped metastable or unstable state formed during rapid evaporation or cooling, with water raising mobility so that thermodynamically favoured separation can occur; the authors judge this less likely [rests on: R27; cited: ref 35] | p.36 |

## 2017 Mugheirbi — Insights into Water-Induced Phase Separation in Itraconazole–Hydroxypropylmethyl Cellulose Spin Coated and Spray Dried Dispersions · ASD process / ASD process

[2017-mugheirbi-water-induced-phase-separation-itz-hpmc-asd](../../../cards/2017-mugheirbi-water-induced-phase-separation-itz-hpmc-asd/paper.html) · ASD process / ASD process · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C39 | claim, mechanism, authors: "Our results therefore suggest" | ITZ–HPMC is thermodynamically miscible as a dry binary ASD but becomes kinetically trapped in a phase-separated state when made from a water-containing solvent; the phase separation has thermodynamic and kinetic components. [rests on: R1, R3, R10, R26] | p.4397−4398 |
| C41 | claim, mechanism, authors: "will"; "may result" | As DCM and then MeOH leave, the solvent becomes enriched in water, ITZ exceeds its miscibility limit and phases separate; further drying may bring the system back into a miscible region, but low molecular mobility traps the phase-separated state. [rests on: argument only] | p.4398 |

## 2022 Duong — Combining enabling formulation strategies to generate supersaturated solutions of delamanid: In situ salt formation during amorphous solid dispersion fabrication for more robust release profiles · Dissolution / B. Supersaturation from ASD dissolution

[2022-duong-delamanid-in-situ-salt-asd-release](../../../cards/2022-duong-delamanid-in-situ-salt-asd-release/paper.html) · Dissolution / B. Supersaturation from ASD dissolution · used · as: kinetic trapping

| id | kind | content | locator |
|---|---|---|---|
| C45 | claim, mechanism, authors: asserted ("Clearly") | The solvent evaporation rate decides whether the material is trapped before nucleation and growth; rotary evaporation was not fast enough, even with polymer, giving ASDs with residual crystallinity [rests on: R8; cited: refs 46, 49] | p.139 |
| C46 | claim, generalisation, authors: "It is likely" | Faster-evaporation processes such as spray drying could likely give crystal-free free-base ASDs at higher DL [rests on: argument only] | p.139 |