Syringe Filters, 4mm, CA, 0.45um Pore Size. Orange Polypropylene, AQ Brand. 1000/CS.
Additional Info:
The 58045-CA04-K AQ™ Syringe Filters are pharmaceutical-grade, high-throughput micro-volume membrane filters designed for HPLC sample preparation and dissolution testing in regulated laboratory environments. Featuring a 0.45 µm Cellulose Acetate (CA) membrane, these filters provide consistent performance, low extractables, and reliable chromatographic results, even with very small sample volumes.
Cellulose Acetate membranes are naturally hydrophilic and surfactant-free, eliminating extractable contaminants common in many hydrophilic filters. With very low protein binding, they are ideal for biological and aqueous samples where maximum recovery is critical.
✅ Critical Compliance Advantage (No Flush Required)
Validated to meet key regulatory standards:
US FDA CFR Title 21, Part 211.92 – minimum fiber release
USP <788> – particulate matter in injectables
USP “Sterile Water for Injection”
Benefits:
✅ No initial flushing required
✅ No 20 µL discard required
✅ Maximizes recovery of micro-volume samples
✅ Reduces risk of failed methods
Performance & Design
The 0.45 µm pore size is optimized for sample clarification and prefiltration, delivering fast flow and minimal clogging.
The 4 mm format minimizes hold-up volume, making it ideal for micro-volume and high-value samples, while the 1000/case packaging supports high-throughput laboratories and production workflows.
CA membranes perform best in aqueous and biological applications, where low protein binding and clean baselines are critical.
The orange housing allows quick identification, and each case includes a Certificate of Analysis.
Key Features
0.45 µm Cellulose Acetate Membrane (Pharma Grade)
Ideal for aqueous and biological samples
Surfactant-free, low extractables
✅ No Initial Flush Required (Validated)
No 20 µL discard required
Low Protein Binding
Maximizes analyte recovery
Hydrophilic Membrane
No pre-wetting required
Ultra-Low Volume Format (4 mm)
Minimizes hold-up volume
Maximizes recovery
Bulk Packaging (1000/Case)
Reduces cost per analysis
Ideal for high-throughput labs
Regulatory Compliance
FDA CFR 21 (211.92), USP <788>
Color-Coded (Orange)
Identifies CA filters
Typical Applications
HPLC & UHPLC Sample Preparation – micro-volume aqueous filtration
LC‑MS Workflows – high-value sample recovery
Biological Samples – protein / biomolecule filtration
Dissolution Testing – pharmaceutical QC
High-Throughput Laboratories – consistent performance
Specifications
Membrane Material: Cellulose Acetate (CA)
Pore Size: 0.45 µm
Diameter: 4 mm
Housing: Polypropylene (PP)
Color Code: Orange
Protein Binding: Low
Hydrophilicity: Hydrophilic
Extractables: None detectable (no flush required)
Initial Discard Volume: None (20 µL not required)
Sterilization: Autoclave or EO
Compliance: FDA CFR 21, USP <788>
Pack Size: 1000/Case
Brand: AQ™
Resources & Ordering Options
Purchase Cellulose Acetate syringe filters, 0.45 µm, 4 mm – 50/pack quantity
Order Cellulose Acetate syringe filters, 0.45 µm, 4 mm – 100/pack quantity