TABLE 1.

Composition of recording solutions for fluoride-containing (referred to as standard internal) and fluoride-free (referred to as FF internal) experiments.

Constituent	Internal recording solution			External recording solution	ChipFill external solution (divalent-free)
	Standard	Standard-KCa3.1*	FF	Standard (incl. KCa3.1)/FF	Standard (incl. KCa3.1)/FF
K-gluconate		30	120
K-Fluoride	120	80
NaCl	10	10	10	80	140
NMDG-Cl				60
KCl	10	10	10	4	4
CaCl2				2
MgCl2				1
EGTA	5	10	5
Glucose				5	5
HEPES	10	10	10	10	10
pH	7.2	7.2	7.2	7.4	7.4
Osmolarity (mOsm)	∼285	∼285	∼285	∼289	∼289

Concentrations are given in mM. Note that for experiments involving K_Ca3.1, CaCl₂ was added to the internal solution as described in Section “Automated patch clamp electrophysiology.”

*In recordings with free [Ca²⁺ > 1 μM] 10 mM HEDTA was used instead of EGTA.