Skip to content
HC Technology
Methylparaben
Categories:
Pharmaceutical Excipients

Methylparaben

Alias
Methyl p-hydroxybenzoate / Methyl 4-hydroxybenzoate / 4-Hydroxybenzoic acid methyl ester / Nipagin / Methylparaben (pharmacopoeia)
CAS No.
Molecular Formula
C8H8O3
Structure
Methylparaben Chemical Structure
Product Details

Product Overview

Usage

Used as an antimicrobial preservative in pharmaceutical excipients with strong inhibitory effects against molds and yeasts. Widely applied in oral liquid preparations, topical ointments, creams, injections and various other pharmaceutical dosage forms. Often combined with other parabens (such as propylparaben) at different ratios to enhance the antimicrobial spectrum. Also used for preservation in eye drops, syrups and mixtures.
Specifications

Technical Specifications

Appearance White or off-white crystals or crystalline powder
Content (on dried basis) 98.0%–102.0%
Melting point 125–128℃
Acidity Compliant (0.1 mol/L NaOH consumption ≤0.1 mL)
Solution clarity and color Clear and colorless
Chloride (Cl) ≤0.035%
Sulfate (as SO₄) ≤0.024%
Related substances Individual impurity ≤0.4%, total impurities ≤0.8%; p-hydroxybenzoic acid ≤0.3%
Loss on drying ≤0.5% (silica gel desiccator, vacuum dried to constant weight)
Residue on ignition ≤0.1%
Heavy metals ≤10 ppm
Arsenic ≤0.0001%
Logistics

Packaging, Storage & Transport

Packaging

25 kg fiber drum, double polyethylene liner

Storage

Store tightly closed in a cool, dry, well-ventilated place

Transport

Transport as general chemicals; protect from moisture, sunlight and physical damage; keep packaging intact