Whole-cell tools

Ephys solution calculator

LIVE CALCULATION

NMDG Cutting Solution (Ting)

Ting et al. (2018) NMDG-HEPES aCSF. Evidence & sources →

Final volume1.000 L finished solutionmL

Powder · weigh Stock · pipette

Compound	Stock mM	Add
NMDG	—	17.96 g
KCl		2.50 mL
NaH₂PO₄		1.25 mL
NaHCO₃	—	2.52 g
HEPES	—	4.77 g
D-glucose (anhydrous)	—	4.50 g
Thiourea	—	0.15 g
Sodium ascorbate	—	0.99 g
Sodium pyruvate	—	0.33 g
CaCl₂		0.50 mL
MgSO₄		10.00 mL

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.
Titrate with HCl to pH 7.3–7.4 before adding calcium and magnesium to reduce precipitation. Add HCl to measured pH, not as a fixed calculated ingredient.
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)

Batch summary

Final volume: 1,000 mL
Nominal solute total: 191.3 mM
Solids to weigh: 31.22 g
Stocks to add: 14.25 mL

Calculation

Powder

g = mM × mL × MW ÷ 1,000,000

Stock

mL = C₁ × Vfinal ÷ Cstock

Verify the exact molecular weight, salt form, hydration state, and assay on the supplier label. Adjust pH experimentally, bring to final volume, and measure osmolality; nominal mM is not an osmolality prediction.

NMDG protective cutting solution

The Ting NMDG protective-recovery method uses reduced sodium during tissue preparation. Its cutting and recovery sequence matters as well as the ingredient list. Follow the published protocol for the transition from protective recovery to holding solution.

Ting et al. (2018): acute brain-slice preparation

External solution recipe

NMDG Cutting Solution (Ting)

External solution · slicing and initial recovery

Final volume1000.0 mL

Compound	Final (mM)	MW (g/mol)	Source	Stock (mM)	Add
NMDG	92	195.21	Powder	—	17.96 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	0.5	147.02	Stock solution	1,000	0.50 mL
MgSO₄	10	246.47	Stock solution	1,000	10.00 mL

Solids to weigh31.22 g

Stocks to add14.25 mL

Nominal solute total191.3 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.
Titrate with HCl to pH 7.3–7.4 before adding calcium and magnesium to reduce precipitation. Add HCl to measured pH, not as a fixed calculated ingredient.
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/

Feedback