PIPES is a zwitterionic N-substituted aminosulfonic acid "Good" buffer. Buffers can be made by adding a solution of base to PIPES free acid, titrating to the appropriate pH, or by mixing equimolar solutions of the sesquisodium salt and the disodium salt or dipotassium salt, titrating to the appropriate pH.
PIPES is used to buffer glutaraldehyde fixative solutions when fixing plant and/or animal tissue tissue samples. This will help prevent the loss of lipids. It is used to buffer glutaraldehyde and formaldehyde when fixing fungal zoospores for fluorescence microscopy and electron microscopy.
Key Applications: Buffer
Application Areas: Molecular Biology
Product Type: Biochemicals
Chemical Class: Buffers
Melting Point: > 300°C decomposes (Lit.)
UV/Visible Absorbance: <0.05 OD260 (0.1 M in 0.2 M NaOH),<0.05 OD280 (0.1 M in 0.2 M NaOH)
Presentation: White Powder
Format: Free Acid
pH: Effective Buffering pH Range 6.1 to 7.5
pKa: 6.8 at 25°C; 6.66 at 37°C
NOTES: Zwitterionic Buffer, Effective buffering range: 6.1 - 7.5 (Merck Index reports 6.0 to 8.5 ), ΔpK/ΔT: 0.0085
Solubility: Pipes free acid is not very water soluble (approximately 1 g/L at 100°C) but will solubilize in 0.5 M NaOH
Storage & Handling: Store at Room Temperature (15-30°C). Store dessicated.