Description

Levothyroxine EP Impurity B is a high-purity reference standard critical for pharmaceutical quality control and analytical research. This compound is essential for the accurate identification, quantification, and monitoring of related substances in Levothyroxine Sodium active pharmaceutical ingredient (API) and its finished dosage forms. It is primarily utilized by pharmaceutical manufacturers, analytical laboratories, and regulatory bodies to ensure product safety, efficacy, and compliance with stringent pharmacopeial standards like the European Pharmacopoeia (EP).

Application

• Pharmaceutical Impurity Profiling: Serves as a certified reference standard for the identification and quantification of specified impurities in Levothyroxine Sodium API and drug products as per EP, USP, and ICH guidelines.
• Analytical Method Development & Validation: Used as a critical system suitability component for developing and validating stability-indicating HPLC, UPLC, or LC-MS methods.
• Quality Control (QC) Testing: Employed in routine batch release testing within pharmaceutical QC laboratories to ensure impurity levels are within acceptable limits.
• Stability Studies: Acts as a marker to track impurity formation and degradation pathways during forced degradation and long-term stability studies of Levothyroxine formulations.
• Regulatory Submissions: Provides essential data for drug master files (DMFs), investigational new drug (IND) applications, and new drug applications (NDAs) to demonstrate comprehensive impurity control.
• Research & Development: Used in pharmaceutical R&D for studying the synthesis, metabolism, and degradation chemistry of thyroid hormone analogs.

Basic Information

Product Name	Levothyroxine EP Impurity B
CAS No.	1628720-66-0
Molecular Formula	C15H11I4NO4
Molecular Weight	776.87 g/mol
Synonyms	O-(4-Hydroxy-3,5-diiodophenyl)-3,5-diiodo-L-tyrosine Impurity B; Thyroxine Impurity B; T4 Impurity B; L-Thyroxine EP Impurity B; 3,5,3',5'-Tetraiodothyronine Related Compound B; (2S)-2-Amino-3-[4-(4-hydroxy-3,5-diiodophenoxy)-3,5-diiodophenyl]propanoic acid
EINECS	Contact for details

Quality Control

Our Levothyroxine EP Impurity B is manufactured and handled under strict quality systems. Each batch undergoes rigorous analytical testing, including HPLC for purity and identity confirmation (IR, MS), to ensure it meets the exacting standards required for use as a reference material. A comprehensive Certificate of Analysis (COA) is provided with each shipment, detailing batch-specific results for identity, purity, and related substances. Our quality commitment aligns with the requirements of pharmacopeial standards (EP/USP) and ICH Q3B(R2) guidelines for impurities in new drug substances.

Storage

Preserve in a tightly closed container, protected from light. Store in a cool, dry place at a controlled room temperature (15-25°C). This product is hygroscopic (moisture-sensitive) and must be kept in a desiccated environment to maintain stability and purity. For long-term storage, consider storing under an inert atmosphere.

Specification

Item	Specification
Appearance	White to off-white powder
Identification (IR)	Conforms to reference spectrum
Identification (HPLC)	Retention time corresponds to reference standard
Purity (HPLC)	≥ 98.0%
Related Substances (HPLC)	Total impurities ≤ 2.0% Any individual unknown impurity ≤ 0.5%
Water Content (KF)	≤ 1.0%
Residue on Ignition	≤ 0.1%

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