pH Meter

An electrode-based instrument for accurately measuring the pH of tissue culture media before autoclaving. Most MS-based media require pH 5.6–5.8; pH below 5.0 weakens agar gel strength, while pH above 6.0 reduces nutrient availability. Calibrate with two-point buffer standards (pH 4.0 and 7.0) before each session. Rinse the electrode with deionized water between samples and store it in the manufacturer's storage solution — never in deionized water.