Name: China Manufacturer Supply High Quality Colistin Sulfate CAS 1264-72-8 with good price
Brand: Wuhan Fortuna Chemical Co., Ltd.

Specifications of Colistin Sulfate CAS 1264-72-8

Item	Specifications	Results
Appearance	White or almost, hygroscopic powder	Conforms
Sulphate ash	≤1.0%	0.39%
Loss on drying	≤3.5%	2.3%
Assay(Dried substance)	≥19000 IU/mg	23132 IU/mg

Parameters of Colistin Sulfate CAS 1264-72-8

Product parameters
Cas number:	1264-72-8
Appearance:	White or almost, hygroscopic powder
Purity:	19000 IU/mg min
Package details:	450Bou/Box
Brand:	Fortunachem

Colistin sulfate is the salt form of colistin, an old antibiotic that belongs to the polymyxin class. It is a last-resort treatment for severe, multidrug-resistant Gram-negative bacterial infections.

A critical distinction must be made right away: Colistin sulfate is primarily used for intestinal decontamination (oral or topical use), whereas its sibling compound, colistimethate sodium, is used for systemic infections (injection into the bloodstream or muscles).

1. Chemical Structure and Classification

Chemical Class: It is a cationic polypeptide antibiotic. Its molecule is a decapeptide (10 amino acids) with a fatty acid tail.
Charge: It is positively charged (polycationic).
Form: Colistin sulfate is the stable, acidic salt form of colistin.

2. Mechanism of Action (How it Kills Bacteria)

Colistin sulfate has a unique and potent mechanism that disrupts the very integrity of the bacterial cell:

Targets the Outer Membrane: It primarily targets the outer membrane of Gram-negative bacteria (e.g., E. coli, Klebsiella, Pseudomonas aeruginosa, Acinetobacter baumannii).
Displaces Magnesium and Calcium: The positively charged colistin molecules displace the divalent cations (Mg²⁺ and Ca²⁺) that stabilize the negatively charged lipopolysaccharide (LPS) molecules in the outer membrane.
Disrupts Membrane Integrity: This disruption causes the outer membrane to become permeable and leaky.
Causes Cell Lysis: The bacterium loses control over its internal contents, essential molecules leak out, and it ultimately dies (a bactericidal effect).

In simple terms, it punches holes in the bacterium's protective outer shell, causing it to fall apart.

3. Common Uses and Applications

Because colistin sulfate is not well absorbed from the gut, its use is targeted:

Oral Administration (for Gut Decontamination):

Treatment of Enteric Infections: Used to treat gastrointestinal infections caused by susceptible Gram-negative bacteria.
Selective Digestive Decontamination (SDD): In critically ill patients in intensive care units, it is used orally to eliminate potentially harmful Gram-negative bacteria from the gut, reducing the risk of systemic infections like ventilator-associated pneumonia.

Topical Application:

Used in powders, ointments, or solutions to treat bacterial skin, ear, and eye infections caused by susceptible organisms.

Veterinary Medicine:

Colistin sulfate has been widely used in agriculture for the treatment and prevention of enteric infections in livestock (pigs, poultry, cattle). This use is highly controversial as it contributes to the development and spread of antibiotic resistance.

4. The Critical Distinction: Colistin Sulfate vs. Colistimethate Sodium

This is the most important practical point to understand.

Feature	Colistin Sulfate	Colistimethate Sodium
Also Known As	...	Colistin methanesulfonate, CMS
Chemical Form	Active form of the antibiotic	A prodrug (inactive form)
Absorption	Not absorbed from the gut or skin.	Can be given by injection (IV/IM) for systemic effect.
Primary Use	Local/Topical: Gut decontamination, skin/ear infections.	Systemic: Serious bloodstream, lung, or urinary tract infections.
Activation	Already active.	It must be converted in the body to active colistin.

In summary: You would take colistin sulfate by mouth to treat a gut infection, but a doctor would administer colistimethate sodium intravenously to treat sepsis or pneumonia.

5. Important Considerations and Side Effects

Nephrotoxicity (Kidney Damage): This is the most significant and well-known side effect of colistin, particularly with the systemic (IV) form. Kidney function must be closely monitored during treatment.
Neurotoxicity (Nerve Damage): Can cause dizziness, confusion, tingling sensations (paresthesia), and even respiratory paralysis at high doses.
Antibiotic Resistance: Colistin is a drug of last resort. The emergence and spread of the mcr-1 gene and other resistance mechanisms, which make bacteria resistant to colistin, is a major global public health threat. Its use in agriculture has significantly contributed to this problem.
Dosing: Dosing is complex and is often calculated based on ideal body weight and kidney function.

Summary

Colistin sulfate is a last-resort polypeptide antibiotic used to combat dangerous Gram-negative bacteria. Its primary role is for local treatment of the gastrointestinal tract or skin, where it is not absorbed into the bloodstream. Its power is tempered by significant toxicity (especially to the kidneys) and the grave threat of increasing bacterial resistance, making its use a carefully considered decision in human medicine.