Description

Benzathine Benzylpenicillin is a long-acting, sparingly soluble salt form of the classic β-lactam antibiotic, benzylpenicillin. This formulation is critical for providing sustained therapeutic levels of penicillin over extended periods, which is essential for effective treatment regimens. It is primarily required by the pharmaceutical industry for the manufacture of injectable depot formulations used in human and veterinary medicine to treat and prevent susceptible bacterial infections.

Application

• Pharmaceutical Active Ingredient (API): Primary use in the manufacture of long-acting injectable antibiotic formulations for human use, particularly for the treatment of streptococcal infections (e.g., rheumatic fever prophylaxis, syphilis).
• Veterinary Pharmaceuticals: Key component in sustained-release injectables for the treatment of bacterial infections in livestock and companion animals.
• Research & Development: Used as a reference standard and in biochemical research studying penicillin mechanisms, resistance, and long-acting drug delivery systems.
• Preventive Medicine Programs: Essential for large-scale public health initiatives requiring prolonged antibiotic coverage from a single administration.

Basic Information

Product Name	Benzathine Benzylpenicillin
CAS No.	1538-09-6
Molecular Formula	C48H56N6O8S2 • 2C16H18N2O4S
Molecular Weight	909.12 g/mol (as free base)
Synonyms	Benzathine Penicillin G; Penicillin G Benzathine; Benzathine Benzylpenicillinum; N,N'-Dibenzylethylenediamine benzylpenicillin; Benzylpenicillin Benzathine; Long-acting Penicillin; DBED Penicillin; Bicillin (trade name); Tardocillin (trade name); Permapen (trade name)
EINECS	216-279-9

Quality Control

Our Benzathine Benzylpenicillin is manufactured and tested to meet stringent pharmacopeial standards, including USP and EP monographs. Every batch undergoes comprehensive analytical testing for identity, potency, and purity. A detailed Certificate of Analysis (COA) confirming compliance with specifications is provided with each shipment, ensuring traceability and quality assurance for our global pharmaceutical partners.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at controlled room temperature (15-25°C). This product is hygroscopic (moisture-sensitive) and must be kept in a low-humidity environment to prevent degradation and clumping.

Specification

Item	Specification
Appearance	White or almost white, crystalline powder
Identification (IR)	Conforms to standard
Identification (HPLC)	Retention time corresponds to reference standard
Assay (HPLC)	96.0% - 102.0% (on anhydrous basis)
Water (Karl Fischer)	≤ 5.0%
pH (Suspension)	5.0 - 7.5
Specific Optical Rotation	+285° to +310° (calculated on anhydrous basis)
Benzathine Content	23.0% - 27.0%
Related Substances (HPLC)	Individual impurity ≤ 2.0%; Total impurities ≤ 5.0%
Sterility (for sterile grade)	Complies with test
Bacterial Endotoxins	< 0.05 EU/mg (for injectable grade)

Note: Specifications can be tailored. Please contact us for the detailed technical data sheet of a specific grade.