Synonym(s): 3-(Cyclohexylamino)-2-hydroxy-1-propanesulfonic acid sodium salt

Description

CAPSO, sodium salt: Molecular Formula: C9H18NO4SNa Molecular Weight: 259.30 The most common buffer for the blotting of proteins to nitrocellulose is the Tris-Glycine buffer (pH 8.3). The transfer of strongly basic proteins is very poor (~20 %). The use of more alkaline transfer buffers (e.g. 25 mM CAPSO, pH 10.0 with 20 % Ethanol or 25 mM AMPSO, pH 9.5) allows for the almost complete transfer of strongly basic proteins from gels to nitrocellulose without lowering the transfer efficiency for other proteins. CAPSO (N-cyclohexyl-2-hydroxyl-3-aminopropanesulfonic acid) sodium salt is used to formulate CAPSO buffer, a zwitterionic buffer that is useful in the range of pH 8.9 - 10.3. CAPSO buffer is used in western and immunoblotting experiments as well as protein sequencing and identification. Used in the electrotransfer of proteins to PVDF or nitrocellulose membranes .The high pH of this buffer makes it useful for the transfer of proteins with a pI > 8.5. CAPSO is not one of the original “Good” buffers, although it has a similar structure to the other propanesulfonic acids and was selected as a highly water soluble buffering reagent with an optimum buffering pH of 10.4 and minimal reactivity with enzymes or proteins, minimal salt effects.

Specifications

Item	Value
Chemical Name	CAPSO Sodium Salt
Appearance	White Powder
CAS No.	102601-34-3
Molecular Formula	C9H18NO4SNa
Molecular Weight	259.3
Grade	Biochemical Grade
Purity	≥99.0%
Moisture	≤3.0%
Infrared	Complies with Specifications
pH of 1% Aqueous Solution(25℃)	10.9-11.6
10% Water Solubility	Colorless, Clear
A280 (in 0.1M Water)	≤0.050
A260 (in 0.1M Water)	≤0.050
Storage / Handling	Store at Room Temperature.

Features

High purity & biochemical grade — ≥ 99.0% purity ensures consistent, reliable performance for sensitive protein work.
Optimal high‑pH buffering (pH 8.9–10.3) — maintains stable alkaline conditions ideal for transferring basic or high‑pI proteins that often fail under standard buffers.
Improved protein transfer efficiency — enables nearly complete electrotransfer to PVDF or nitrocellulose membranes, even for strongly basic proteins.
Zwitterionic buffer with low reactivity — minimal interaction with proteins or metal ions, preserving enzyme activity and protein integrity.
Highly water-soluble & easy to handle — dissolves readily in aqueous solution; stable at room temperature for convenient lab storage and use.

Applications

Electrotransfer of proteins from SDS‑PAGE gels to PVDF or nitrocellulose membranes in western blotting or immunoblotting.
Transfer of proteins with high isoelectric points (pI > 8.5), including basic or strongly charged proteins.
Protein sequencing or identification workflows that require high‑pH transfer buffers and minimal buffer interference.
Immunodetection assays where standard Tris–Glycine buffers produce poor transfer of basic proteins.
Biochemical research requiring stable alkaline buffering, minimal metal-binding, and high reproducibility.

Safety Disclaimer

This product is intended for laboratory research use only. Not for drug, human, or veterinary use. Review the Safety Data Sheet (SDS) provided by BioFargo for detailed handling, storage, hazard, and disposal information. Use appropriate personal protective equipment (PPE) including gloves, lab coat, and eye protection when handling. Dispose of waste and residual buffer in accordance with local, state, and federal regulations. Ensure proper ventilation if preparing large volumes or heating solutions.

Documents

INFO

COA

SDS

CAPSO Sodium Salt 99.0% Biochemical Grade