Cystine Disodium Salt
As a salt of a dibasic amino acid, Cystine Disodium Salt exhibits typical amphoteric characteristics, with its ionization state closely dependent on the pH of the solution.
- In acidic conditions (pH < 3.0): The carboxylate anions (−COO−) accept protons and are converted back to carboxyl groups (−COOH). As the pH decreases, the solubility of the compound drops sharply, and free L-cystine precipitates out of the solution. This reaction is the basis for the industrial preparation of L-cystine from Cystine Disodium Salt—acidification with dilute hydrochloric acid or sulfuric acid triggers crystallization of L-cystine with high purity.
- In neutral to weakly alkaline conditions (pH 7.0–9.0): The compound exists stably as a zwitterion, with carboxylate groups in the anionic form and amino groups protonated to −NH3+. This is the most stable state for Cystine Disodium Salt in aqueous solutions, and it remains fully dissolved, making it suitable for formulating oral or injectable preparations.
- In strongly alkaline conditions (pH > 12.0, with heating): The disulfide bond is prone to cleavage under the action of strong bases (e.g., 40% NaOH solution), producing sodium cysteinate. Prolonged heating accelerates this hydrolysis reaction, which is a common method for preparing L-cysteine from Cystine Disodium Salt in the laboratory.
The isoelectric point (pI) of the corresponding free L-cystine is approximately 5.05, but Cystine Disodium Salt itself does not have a distinct isoelectric point due to its pre-ionized carboxylate groups; its solubility minimum occurs at pH close to the pI of L-cystine.
在线联系供应商
Other supplier products
 |
Cystine Disodium Salt | Cystine Disodium Salt is used as a standard reference material in biochemical analysis due to its high purity and stable chemical properties: ... |
 |
L-Cysteine S-Sulfate Na | Density and Bulk Properties of L-Cysteine S-Sulfate Na Crystal density: The crystal density of the purified product is approximately 1.65–1.7... |
 |
Phospho-L-Tyrosine Disodium Salt | Handling and Storage of Phospho-L-Tyrosine Disodium Salt Storage Conditions: Store at -20℃ in a sealed, light-protected container; avoid repeated ... |
 |
BOC-L-GLU(ME)-OME | During the storage and transportation stages, BOC-L-GLU(ME)-OME is an amino acid derivative that is prone to moisture absorption and hydrolysis. It... |
 |
Cystine Disodium Salt | Cystine Disodium Salt exhibits superior stability compared to free L-cystine and cysteine, reducing degradation risks during production, storage, a... |
Same products
 |
Easy-cleaning Silicone-Modified Waterborne UV Resin | 卖方: Guangzhou Human New Material Science and Technology Co., Ltd | LUV533 is a high-performance, silicone-modified hexafunctional waterborne UV resinengineered to d... |
 |
Water-based Soft-Touch Resin for Consumer Electronics | 卖方: Guangzhou Human New Material Science and Technology Co., Ltd | Water-based Soft-Touch Resinis an advanced coating material formulated to deliver a luxurious, ve... |
 |
Conformal Coatings | 卖方: Guangzhou Human New Material Science and Technology Co., Ltd | The conformal coatingsprovide good adhesion to metal, PCB and other substrates after curing at ro... |
 |
Metalized & Laser Transfer coating | 卖方: Guangzhou Human New Material Science and Technology Co., Ltd | Metallized and laser transfer coatingsare designed with sustainability in mind, ensuring minimal ... |
 |
Hydrophilic coatings for Air Conditioner | 卖方: Guangzhou Human New Material Science and Technology Co., Ltd | A water-based coating combination applied on the surface of aluminum foil, which forms a layer wi... |
