Latex-based liquid components for quantifying free Protein S in human citrated plasma using readers with wavelengths 600-800nm.

MRX FPS consists of sub-micron sized polystyrene particles coupled to two different monoclonal antibodies specific for protein S.

This system is not sensitive to protein S bound to C4b-binding protein, but only reacts with the free active form of protein S. When the reagent is exposed to a plasma sample containing free Protein S, the particles will agglutinate, giving rise to increased light-scattering. MRX FPS is suitable for automatic coagulation and clinical chemistry instruments using turbidimetric detection in the 600 – 800 nm wavelength range.

Latex based assay

High precision

Specific for free protein S

Good correlation to existing Free Protein S assays

Calibrated against WHO 2nd International Standard,
NIBSC 03/228

Sensitivity & specificity

Details & typical data

Product form: Liquid components
Available volumes: • MRX153: 2.5 mL latex + 4 mL reaction buffer
• Other filling volumes upon request
Origin: Monoclonal antibodies
Additional products needed: • Eximius Control Plus (L1/L2/L3) (MRX180-MRX183)
• Scandinavian Controls Multi Plus (GHI164/GHI170)
• FPS Calibrator (MRX1206)
• Sample Diluent (0,9 % NaCl) for calibrator dilutions (MRX184)
• Diluent (GHI154)
Wavelength: 600-800 nm
Linear range: 20-150 (FPS %)
Precision: Intra-device (CV %):
• L1: 4.01
• L2: 2.83
• L3: 3.01
Interfering substances: No interferences with UF and LMW Heparin <100 U/mL, Bilirubin < 0,8 g/L, Triglycerides <30 g/L, Hemoglobin <10 g/L

Stability & storage

Storage: 2-8 °C
Shelf-life: 18 months at 2-8 °C
Open vial stability: 4 weeks at 2-8 °C / 4 weeks at 2-25 °C

Ordering information

Ref. No Product description Size
MRX153 MRX FPS (latex + reaction buffer) 3x2.5 mL + 3x4 mL
MRX180 Eximius Control Plus, L1+L2+L3 4+4+2x1 mL
MRX181/182/183 Eximius Control Plus L1/L2/L3, 10x1 mL pack per level
GHI164/170 Scandinavian Control Multi Plus, L1/L2 10x1 mL pack per level
MRX1206 FPS Calibrator 1x1 mL
MRX184 Sample Diluent (0,9 % NaCl) 10x8 mL
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