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HEPES Holding Solution (Ting)
Ting et al. (2018) HEPES holding aCSF. Evidence & sources →
Powder · weigh Stock · pipette
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HEPES holding solution
The Ting HEPES holding solution is a distinct stage of the protective-recovery workflow. It is not interchangeable with the NMDG cutting solution. Follow the published recovery and holding conditions before transferring slices to the recording chamber.
Ting et al. (2018): recovery and holding protocolExternal solution recipe
HEPES Holding Solution (Ting)
External solution · holding
Final volume1000.0 mL
| Compound | Final (mM) | MW (g/mol) | Source | Stock (mM) | Add |
|---|---|---|---|---|---|
| NaCl | 92 | 58.44 | Powder | — | 5.38 g |
| KCl | 2.5 | 74.55 | Stock solution | 1,000 | 2.50 mL |
| NaH₂PO₄ | 1.25 | 119.98 | Stock solution | 1,000 | 1.25 mL |
| NaHCO₃ | 30 | 84.01 | Powder | — | 2.52 g |
| HEPES | 20 | 238.30 | Powder | — | 4.77 g |
| D-glucose (anhydrous) | 25 | 180.16 | Powder | — | 4.50 g |
| Thiourea | 2 | 76.12 | Powder | — | 0.15 g |
| Sodium ascorbate | 5 | 198.11 | Powder | — | 0.99 g |
| Sodium pyruvate | 3 | 110.04 | Powder | — | 0.33 g |
| CaCl₂ | 2 | 147.02 | Stock solution | 1,000 | 2.00 mL |
| MgSO₄ | 2 | 246.47 | Stock solution | 1,000 | 2.00 mL |
Solids to weigh18.64 g
Stocks to add7.75 mL
Nominal solute total184.8 mM
Preparation notes
- KCl, NaH₂PO₄, MgSO₄ and CaCl₂ are added from 1 M (1000 mM) stocks.
- Dissolve powders in ultrapure water below the final batch volume, then add the calculated stock volumes. For NMDG, add calcium and magnesium stocks after HCl titration. Verify powder forms and stock concentrations on reagent labels.
- Saturate with carbogen (95% O₂ / 5% CO₂) before use.
- Verify pH 7.3–7.4 and measured osmolality 300–310 mOsm/kg; bring to the selected final volume.
Source: Ting et al. (2018) — https://pmc.ncbi.nlm.nih.gov/articles/PMC5931343/