VITLAB PTFE-Coated Magnetic Stir Bar

Overview

The VITLAB PTFE-Coated Magnetic Stir Bar is a precision-engineered laboratory component designed for reliable, contamination-free agitation in glass, plastic, or stainless-steel vessels under controlled thermal and chemical conditions. Constructed with a high-grade permanent magnet core fully encapsulated in medical-grade, USP Class VI-certified polytetrafluoroethylene (PTFE), these stir bars deliver exceptional chemical inertness across pH 0–14, resistance to organic solvents, strong acids (including aqua regia), and caustic bases—making them suitable for applications ranging from analytical sample preparation to pharmaceutical synthesis and QC testing. The magnetic coupling operates via rotating external fields generated by standard laboratory magnetic stirrers (e.g., IKA, Thermo Fisher, VELP), relying on torque transmission through ferromagnetic interaction without mechanical contact—ensuring zero wear, silent operation, and minimal heat generation during prolonged use.

Key Features

• Full PTFE encapsulation ensures non-leaching, non-stick surface integrity and eliminates metal ion contamination risks in trace analysis (e.g., ICP-MS, AAS) and cell culture media preparation.
• Dense sintered ferrite or neodymium magnet core provides consistent rotational stability at speeds up to 1,200 rpm in volumes from 10 mL to 2 L, depending on bar geometry and vessel shape.
• Smooth, void-free PTFE finish resists biofilm adhesion and enables rapid, residue-free cleaning via autoclaving (up to 121°C, 2 bar) or solvent rinsing.
• Dimensionally precise cylindrical geometry—available in three standardized sizes (Ø14 × 10 mm, Ø17 × 13 mm, Ø22 × 15 mm)—optimizes vortex formation and mixing efficiency while minimizing splashing or “jumping” in low-viscosity media.
• Individually packaged units (1 per pack) prevent cross-contamination and support traceable inventory control in GLP-compliant laboratories.

Sample Compatibility & Compliance

These stir bars are validated for use with aqueous buffers, ethanol, acetone, chloroform, concentrated HNO₃/H₂SO₄, NaOH (up to 50% w/w), and high-purity solvents used in HPLC mobile phase preparation. They exhibit no detectable leachables per USP and meet ISO 10993-5 cytotoxicity requirements. The PTFE coating conforms to FDA 21 CFR §177.1550 for repeated food-contact use, supporting applications in nutraceutical and clinical diagnostic workflows. No silicone or epoxy binders are used in manufacturing—eliminating volatile organic compound (VOC) outgassing during heating.

Software & Data Management

As a passive hardware component, the VITLAB PTFE stir bar requires no embedded firmware, calibration, or software integration. However, it is fully compatible with digital stirrer platforms featuring speed logging, temperature synchronization (e.g., IKA RET control visco), and audit-trail-enabled controllers compliant with FDA 21 CFR Part 11. Laboratory Information Management Systems (LIMS) may track lot-specific usage via supplied VITLAB product codes (e.g., 314097, 314197, 314297) for full traceability in regulated environments.

Applications

• Homogenization of reagent solutions prior to spectrophotometric or titrimetric analysis
• Stirring of enzyme reaction mixtures at 4–37°C without denaturation risk
• Preparation of calibration standards for elemental analysis (ICP-OES, GF-AAS)
• Agitation during solid-phase extraction (SPE) conditioning and elution steps
• Mixing of sterile cell culture media in laminar flow hoods using non-ferrous stir plates
• Long-term stirring of hydrolysis or esterification reactions under reflux conditions

FAQ

Can these stir bars be used in microwave-assisted digestion vessels?
No—microwave exposure induces eddy currents in the internal magnet, causing rapid localized heating and potential PTFE degradation. Use only in conventional hotplates or ambient-temperature stirrers.
Is the PTFE coating resistant to HF (hydrofluoric acid)?
While PTFE exhibits broad chemical resistance, prolonged exposure to anhydrous HF or >48% aqueous HF may cause slow surface etching; verify compatibility via short-term immersion testing for critical applications.
Do these stir bars require recalibration or periodic replacement?
No calibration is needed. Replacement is recommended after visible abrasion, chipping, or failure to rotate consistently at ≥600 rpm—typically after 50–100 autoclave cycles or 12 months of continuous use.
Are custom dimensions or magnetic strengths available?
VITLAB offers OEM customization including elliptical profiles, multi-pole magnetization, and enhanced coercivity grades upon request—subject to minimum order quantities and lead-time confirmation.