What is CAPSO Anhydrous?

CAPSO Anhydrous (CAS 73463-39-5) is a zwitterionic biological buffer also known as 3-(Cyclohexylamino)-2-hydroxy-1-propanesulfonic acid. This specialized chemical compound is part of the Good’s buffer family, which is widely recognized for its excellent buffering capacity in alkaline pH ranges. CAPSO is supplied in anhydrous form, meaning it contains no water molecules, making it highly stable and ideal for precision laboratory applications.

The molecular formula of CAPSO is C9H19NO4S, with a molecular weight of 237.32 g/mol. As a zwitterion, CAPSO contains both positive and negative charges within the same molecule, which contributes to its excellent buffering properties and minimal interference with biological processes. This unique chemical structure allows CAPSO to maintain pH stability in the highly alkaline range where many other buffers fail to perform effectively.

CAPSO is manufactured to high purity standards, typically ≥99% purity as determined by titration, making it suitable for critical research applications where buffer quality is essential for experimental reproducibility.

What Are the Benefits of CAPSO Anhydrous?

Excellent Buffering at Alkaline pH

The primary benefit of CAPSO Anhydrous is its exceptional buffering capacity in the alkaline pH range. With a useful pH range of 8.9 to 10.3 (some sources indicate 9.6-11.4), CAPSO provides stable pH maintenance for experiments requiring high pH environments. This makes it indispensable for biochemical and molecular biology research that operates in the alkaline range, where maintaining precise pH is critical for enzyme activity, protein stability, and nucleic acid manipulations.

Low UV Absorbance

CAPSO exhibits very low UV absorbance, particularly in the UV range used for spectrophotometry and other optical detection methods. This characteristic significantly reduces interference in UV-sensitive analytical techniques, supporting accurate and reliable experimental outcomes in molecular biology and biochemistry laboratories. Researchers can perform absorbance measurements without significant buffer contribution to the signal.

Low Metal-Binding Constants

Unlike some other buffers, CAPSO has very low metal-binding constants. This means it does not chelate or bind metal ions that may be present in the experimental system, ensuring that metal-dependent enzymes and reactions are not affected by the buffer composition. This property is particularly valuable in studies involving metalloenzymes and biochemical reactions requiring free metal ions.

Non-Interfering with Biological Systems

As part of the Good’s buffer family, CAPSO is designed to be biologically inert and non-interfering with most biochemical reactions. It does not significantly affect enzyme activities, protein structures, or cellular processes when used at appropriate concentrations, making it an ideal choice for sensitive biological experiments.

Versatility in Applications

CAPSO finds applications across a wide range of laboratory techniques, from basic biochemistry to advanced molecular biology methods. Its versatility stems from its stable buffering properties and compatibility with various experimental conditions.

What Are the Uses of CAPSO Anhydrous?

Immunoblotting and Western Blotting

CAPSO is widely used in immunoblotting (, particularly in theWestern blotting) procedures electrotransfer of proteins to PVDF or nitrocellulose membranes. The buffer’s alkaline pH helps ensure efficient protein transfer, especially for strongly basic proteins that require higher pH conditions for optimal transfer efficiency.

Gel Electrophoresis

In gel electrophoresis procedures, particularly for RNA and other macromolecules, CAPSO buffer helps maintain an alkaline environment that ensures the integrity and resolution of the samples. The buffer is especially useful for electrophoresis procedures where alkaline conditions are needed for proper separation and analysis.

Protein Purification and Analysis

CAPSO is used in the purification and analysis of enzymes that operate optimally at higher pH levels. The buffer provides stable conditions for maintaining enzyme activity during purification processes and subsequent analytical procedures. Its low interference properties make it suitable for various protein research applications.

Spectrophotometry and UV-Based Assays

Due to its low UV absorbance, CAPSO is commonly used in spectrophotometric applications and other UV-based analytical techniques. Researchers can perform absorbance, fluorescence, or other optical measurements with minimal buffer-derived interference, leading to more accurate quantitative results.

Cell Culture and Biological Research

In cell-based experiments requiring alkaline conditions, CAPSO provides a biologically inert buffering system that supports cell viability while maintaining the necessary pH for specific experimental requirements.

Cosmetic and Skincare Formulations

Beyond laboratory research, CAPSO finds application in the cosmetic industry, where it is incorporated into skincare formulations for its moisturizing properties, helping improve skin hydration and overall appearance.

Safety and Handling of CAPSO Anhydrous

General Safety Considerations

CAPSO Anhydrous is generally considered safe when handled with appropriate safety precautions standard for laboratory chemicals. However, as with all chemical substances, proper personal protective equipment (PPE) should be worn when handling CAPSO, including lab coat, gloves, and safety goggles. Always consult the Material Safety Data Sheet (MSDS) before working with any chemical.

Storage Conditions

CAPSO should be stored in a cool, dry place away from moisture and incompatible substances. While CAPSO is not typically classified as hygroscopic, protecting it from moisture exposure helps maintain its purity and effectiveness. Appropriate storage temperature is usually room temperature unless otherwise specified by the manufacturer.

Bortskaffelse

Dispose of CAPSO and CAPSO-containing solutions according to local regulations for chemical waste. Do not pour down the drain without checking local guidelines for appropriate disposal methods.

Chemical Specifications

Property	Værdi
CAS-nummer	73463-39-5
Chemical Name	3-(Cyclohexylamino)-2-hydroxy-1-propanesulfonic acid
Molekylær formel	C9H19NO4S
Molekylvægt	237.32 g/mol
Renhed	≥99% (titration, anhydrous basis)
Useful pH Range	8.9 – 10.3
pKa (25°C)	~9.6
Udseende	Hvidt krystallinsk pulver
Opløselighed	Opløselig i vand

Frequently Asked Questions

What is the difference between CAPS and CAPSO?

CAPS (3-Cyclohexylamino-1-propanesulfonic acid) and CAPSO (3-Cyclohexylamino-2-hydroxy-1-propanesulfonic acid) are related but distinct buffers. The key difference is that CAPSO contains an additional hydroxyl (-OH) group, making it a hydroxy-substituted derivative. CAPS has a useful pH range of 9.7-11.1, while CAPSO spans 8.9-10.3. Both are valuable buffers for alkaline applications, with CAPSO offering slightly better solubility.

Can CAPSO be used in place of other buffers?

CAPSO can substitute for other alkaline buffers in many applications, but it should be chosen based on the specific pH requirements of your experiment. Always verify that the buffer’s pKa falls within your desired working pH range and that it does not interfere with your specific experimental system.

Is CAPSO suitable for protein crystallization?

CAPSO’s low interference properties and stable buffering make it suitable for some protein crystallization conditions, particularly those requiring alkaline pH. However, specific crystallization conditions vary widely, and optimization is typically required for each protein system.

How do I prepare a CAPSO buffer solution?

To prepare a CAPSO buffer, dissolve the appropriate amount of CAPSO anhydrous in distilled water. Adjust to the desired pH using sodium hydroxide (NaOH) or hydrochloric acid (HCl) as needed. The final concentration and pH will depend on your specific experimental requirements. Always use calibrated pH meters for accurate pH adjustment.

Why Choose Our CAPSO Anhydrous?

• High Purity Quality: Our CAPSO Anhydrous meets or exceeds ≥99% purity standards, ensuring reliable and reproducible results in your research applications.
• Consistent Batch-to-Batch Quality: We maintain strict quality control measures to deliver consistent product performance across every batch.
• Technical Support: Our team of chemical experts is available to answer your technical questions and provide guidance on buffer preparation and usage.
• Competitive Pricing: We offer quality biochemicals at competitive prices for research institutions and laboratories.
• Reliable Supply: With our established supply chain, you can count on timely delivery of your chemical supplies.

Related Products

If you’re working with CAPSO Anhydrous, you might also be interested in these related chemicals available from Longchang Chemical:

• CAPS Buffer (CAS 1135-40-6) – Another Good’s buffer for alkaline applications
• TRIS Buffer – Common biological buffer for neutral to alkaline pH
• HEPES Buffer – Buffer for physiological pH range
• MES Monohydrate – Buffer for acidic to neutral pH range