# Evidence: drug-silanol hydrogen bonding

Parent: hydrogen bonding · class: molecular interaction · names merged here: drug-silanol hydrogen bonding

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.

## 2019 Dening — Application of an adsorption isotherm to explain incomplete drug release from ordered mesoporous silica materials under supersaturating conditions · Mesoporous silica / Mesoporous silica

[2019-dening-adsorption-isotherm-incomplete-release-sba15](../../../cards/2019-dening-adsorption-isotherm-incomplete-release-sba15/paper.html) · Mesoporous silica / Mesoporous silica · measured · as: drug-silanol hydrogen bonding

| id | kind | content | locator |
|---|---|---|---|
| R8 | record, measured | Qa without and with 5 M urea — Ci 27.5 μg/mL; 50 mM phosphate buffer pH 6.8; 37 °C; P4; mean ± SD, n = 3 — control 259 ± 31 mg/g; 5 M urea 169 ± 37 mg/g; p < 0.05 | Fig. 2 and Section 4.4, p. 190 |
| R12 | record, measured | ATR-FTIR, Si–OH region 3800–3700 cm⁻¹ — samples of R10 (38% w/w) and 22% w/w loaded SBA-15 and PM (Fig. S4) — blank SBA-15: band at 3749 cm⁻¹ (assigned isolated silanols); crystalline and amorphous ritonavir: no band at 3749 cm⁻¹; PM (38% and 22% w/w): band at 3749 cm⁻¹ present; loaded 38% and 22% w/w: band absent; broad low-intensity 3300–3600 cm⁻¹ band of hydrogen-bonded silanols: data not shown | Fig. 4C, p. 191; Section 4.6, p. 192; Fig. S4, SI p. 5 |
| R13 | record, measured | XPS O 1s binding energy — blank SBA-15; amorphous ritonavir; loaded SBA-15 22% w/w; P8 — blank SBA-15: 533.2 eV (silanol); amorphous ritonavir components 531.3 eV (carbonyl), 532.4 eV (ether), 533.6 eV (OH) as assigned; loaded: one broad peak at 532.5 eV; largest changes of all peaks in O 1s | Fig. 6 and Section 4.7, p. 192 |
| C21 | claim, mechanism, authors: suggests; provided indirect evidence | The urea-induced reduction of adsorption suggests that hydrogen bonding is an important ritonavir–SBA-15 interaction, including from supersaturated solution (indirect evidence). [rests on: R8] | Section 4.4, p. 190; Section 5.2, p. 196 |
| C26 | claim, mechanism, authors: provides evidence; supports the supposition | Loss of the 3749 cm⁻¹ isolated-silanol band at two drug loads is taken as evidence that isolated silanols form hydrogen bonds with ritonavir, shifting into the 3300–3600 cm⁻¹ hydrogen-bonded range. [rests on: R12] | Section 4.6, p. 192; Section 5.2, p. 196 |
| C28 | claim, mechanism, authors: suggests; suggesting; further advocates; in support | The O 1s peak of loaded SBA-15 at an energy between the silanol and ritonavir carbonyl energies suggests hydrogen bonds between the two, with silanol as donor and ritonavir carbonyls as acceptors; the ≈0.5 eV lower Si 2p supports this. [rests on: R13, R14] | Section 4.7, p. 192; Section 5.2, pp. 196–197 |
| C52 | claim, mechanism, authors: abstract: asserted; discussion: strongly indicated; appears to drive; collectively indicates; conclusions: asserted ("established") | The data are read as indicating hydrogen bonding with surface silanols as the predominant ritonavir–SBA-15 interaction at all concentrations studied, above and below the crystalline solubility; below and slightly above the crystalline solubility it appears to drive adsorption. [rests on: R8, R9, R12, R13, R15, R16] | Abstract, p. 186; Section 5.2, p. 196; Section 6, p. 198 |

## 2020 Hate — Interplay of Adsorption, Supersaturation and the Presence of an Absorptive Sink on Drug Release from Mesoporous Silica-Based Formulations · Mesoporous silica / Mesoporous silica

[2020-hate-atazanavir-mesoporous-silica-adsorption-absorptive-sink-release](../../../cards/2020-hate-atazanavir-mesoporous-silica-adsorption-absorptive-sink-release/paper.html) · Mesoporous silica / Mesoporous silica · measured · as: drug-silanol hydrogen bonding

| id | kind | content | locator |
|---|---|---|---|
| R12 | record, measured | ATR-FTIR band positions, carbonyl and isolated-silanol regions — crystalline ATZ, melt-quenched amorphous ATZ, SBA-15, ATZ-MPS (P6) — sub-table below | Fig. 7, p.9; text p.8-9 |
| C3 | claim, mechanism, authors: abstract: "indicated"; results: "could indicate"; discussion: "support" | ATZ carbonyl groups and SBA-15 silanol groups interact by hydrogen bonding in the formulations (carbonyl band shifts; loss of the isolated-silanol band from 20% DL) [rests on: R12] | p.1, p.9, p.13 |