What Manufacturers Really Mean by Cefoperazone Molecular Weight

In plant meetings and QC chat threads, I keep hearing the same question: what’s the “real” number for Cefoperazone Molecular Weight? Here’s the practical answer teams use on the floor. The free acid form of cefoperazone clocks in at ≈645.6 g/mol (commonly cited), while the sodium form used in finished drug substance is ≈667.7 g/mol. Context matters—spec sheets often list both, which, to be honest, avoids a lot of confusion when converting dosages or setting up HPLC methods.

Product at a Glance: Cefoperazone Acid (CAS 58739-66-5)

Origin: 80 Hainan Road, Shijiazhuang Economic and Technological Development Area. This Cefoperazone Acid is a core intermediate for third‑generation cephalosporins with strong anti‑pseudomonal relevance. It’s primarily converted to Cefoperazone Sodium for severe infection treatments. In my notebook, I’ve circled one thing repeatedly: consistent pharmacopoeia compliance (USP/EP/ChP) is what keeps batch release drama-free.

Key Specifications and Typical Data

Item	Spec / Result (≈; real-world use may vary)
Identity	IR/NMR conforms; LC-MS m/z consistent with free acid
Cefoperazone Molecular Weight	Free acid ≈645.6 g/mol; Sodium form ≈667.7 g/mol
Assay (HPLC)	≥98.0% (dry basis)
Related substances	Any single ≤0.5%; total ≤1.0% (USP/EP aligned)
Water (KF)	≤1.0%
Residual solvents	Meets ICH Q3C limits (GC)
Heavy metals	ICP-MS: meets pharmacopeial limits
Shelf life	24–36 months sealed, 2–8°C, desiccated, light-protected

Process Flow (What QC actually checks)

Materials: protected cephem nucleus, acylating reagents, controlled base, pharma-grade solvents. Methods: stepwise acylation → deprotection → crystallization → washing → vacuum dry. Testing standards: USP/EP/ChP monographs; in-process HPLC for impurity drift; endpoint confirmation by LC-MS; compendial water and solvent tests. Service life: validated stability under ICH Q1A; re-test possible with trending data (I’ve seen it extended when lots behave well).

Applications and Industries

Vendor Comparison (field-notes style)

Vendor	Compliance	Batch Size	Lead Time	Notes
Hejia Chemical Tech (Hainan Rd, Shijiazhuang)	USP/EP/ChP, ISO 9001; DMF-ready dossier	Up to 50–100 kg	2–4 weeks	Strong impurity control; responsive QC
Supplier B	USP/EP	10–30 kg	4–6 weeks	Good price; limited stability data
Supplier C	ChP	≤20 kg	6–8 weeks	Customization on request

Customization and Documentation

Options: particle size tuning for filtration, impurity profile tightening (e.g., ≤0.3% total), tailored residual solvent targets. Docs: CoA, MOA, MSDS, stability summary, validation package (HPLC/GC KF), and, if needed, CEP support. Customers say the fastest wins happen when method parameters (column, gradient, λ) are shared early.

Case Snapshots

- EU CDMO: cut rejections from 3% to 0.5% after aligning on Cefoperazone Molecular Weight reference, ion pairing, and column lot.
- India sterile site: moved to 100 kg/quarter after solvent switch reduced unknown impurity at RRT 1.12 from 0.45% to 0.18%.

Certifications and Standards

Plant quality: ISO 9001, GMP-aligned operations; testing against USP/EP/ChP. ICH Q7/Q3A/Q3C frameworks applied. Antimicrobial relevance usually cross-checked with CLSI M100 breakpoints during downstream API work (not for the intermediate, but teams like the line-of-sight).