Tag Archives: solution

Intracellular (pipette) solution for whole-cell patch-clamp

This solution will be in dialysis with the cytosol and hence is similar to it in composition (high potassium and low sodium).

Chemical mM MW/concentration for 100 ml
KCl 107 74.55 0.7976 g
CaCl2 1 1 M 100 ul
MgCl2 7 1 M 700 ul
EGTA 11 380.35 0.4183
HEPES 10 238.3 0.2383 g
Na2ATP 5 569.16 0.2846

Adjust to pH to 7.2 using potassium hydroxide (KOH).

Always check the molecular weight on the bottles of the chemicals. It may vary, due to different water contents for example.

Reference

Chimerel et al., Bacterial metabolite indole modulates incretin secretion from intestinal enteroendocrine L cells, Cell Rep., 2014
Link to the article in PubMed

Extracellular (bath) solution for whole-cell patch-clamp in GLUTag cells

This solution is needed to keep cells in a physiological environment during patch-clamp experiments. It also contains glucose as a nutrient.

Chemical mM MW/concentration for 1 L for 500 ml for 500 ml 10X
NaCl 138 58.44 8.065 g 4.0325 g 40.325 g
KCl 4.5 74.55 0.335 g 0.1675 g 1.675 g
NaHCO3 4.2 84.01 0.3528 g 0.1764 g 1.764 g
NaH2PO4 1.2 120 0.144 g 0.072 g 0.72 g
CaCl2 2.6 1 M 2.6 ml 1.3 ml
MgCl2 2.6 1 M 1.2 ml 0.6 ml 6 ml
HEPES 10 238.3 2.382 g 1.1915 g 11.915 g

Glucose: 1 mM (18 MG/100 ml)
pH 7.4 using NaOH
For a 500 ml 1X solution, I added 2.4 ml of NaOH at 1 M concentration.

Add CaCl2 and adjust the pH when the solution concentration is 1X.
Add glucose to the solution needed on the day, usually 50 ml.

Always check the molecular weight on the bottles of the chemicals. It may vary, due to different water contents for example.

Reference

Rogers et al., Electrical activity-triggered glucagon-like peptide-1
secretion from primary murine L-cells, J. Physiol., 2011
Link to the article in PubMed