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Catalog # 090-158 | ProteinSimple a Bio-Techne Brand
MauriceFlex – icIEF, CE-SDS, & icIEF Fractionation

Automated cIEF & CE-SDS analysis, and cIEF fractionation

MauriceFlex combines protein charge isoform fractionation with imaged-capillary isoelectric focusing (icIEF) and CE-SDS analysis in one instrument, so that you can go beyond routine size and charge and conduct an in-depth analysis of your molecule at any stage without needing to rely on different instruments, methods, or expertise. Get compliant data with either Compass for iCE or Waters Empower software (fractionation not supported on Empower).

Purity, identity, heterogeneity, and charge variant fractionation

The potency, safety, and efficacy of your biotherapeutic can be impacted by certain charge variants present, therefore in-depth characterization is crucial. Now, instead of spending weeks or months on ion-exchange chromatography (IEX) based fractionation, detect charge variants of your protein, AND collect their fractions on the same instrument in the same day!
Maurice Flex saves time over IEX for protein fractionation

Spotlight on MauriceFlex

Read to see how MauriceFlex fractionation enables intact and peptide mapping analysis by LC-MS using a NIST mAb sample. You'll learn how:

  • High purity fractionation of charge variants can be obtained in a single day
  • A single fractionation run provides sufficient charge variant fractions for intact mass analysis
  • With enrichment from pooling fractions from multiple runs, charge variants can be analyzed with LC-MS peptide mapping

Citations for MauriceFlex

View all citations for the Imaged Capillary Electrophoresis (iCE) platform.
Please visit our Instrument Citation Database to search our collection of scientific articles that feature our instruments.

Testimonials from your Peers for Imaged Capillary Electrophoresis (iCE)

Showing  1 - 2 of 2 testimonials Showing All

"The short run times and easy sample preparation allowed for method development within a day or two. The versatility of the instrument allows the possibility of offering clients rapid alternatives to traditional ID and charge heterogeneity assays."

Joan Garrison, QC Method Transfer Scientist, Cook Pharmica

Showing  1 - 2 of 2 testimonials Showing All

More Information About MauriceFlex

How icIEF Fractionation Works

  • An applied electric field creates a pH gradient across the capillary inside the MauriceFlex cartridge
  • Proteins with different isoelectric points or pI values migrate along the capillary until they reach pH values matching their pI, leading to focusing and charge separation
  • For fractionation, the catholyte end of the capillary is brought in contact with ammonium acetate
    The applied voltage drives the acetate ions into the capillary from the catholyte end and the proton from the anolyte end
  • The displacement of hydroxide ions by acetate ions gradually changes the pH gradient along the capillary, mobilizing the previously focused proteins to move along the new pH gradient towards the cathodic end 
  • Proteins elute out of the capillary one by one while leaving urea and other impurities behind, giving you high-purity fractions you need for further analysis
Charge variant fraction collection process on MauriceFlex is faster than IEX
Feature cIEF CE-SDS PLUS Turbo CE-SDS cIEF Fractionation
Minimum Sample Volume 50 µL 50 µL 100 µL 100 µL
Sample Delivery Vacuum Electrokinetic Electrokinetic Vacuum
Typical Separation Time 6–10 min (molecule-dependent) Reduced IgG: 25 min, Non-reduced IgG: 35 min Reduced IgG: 5.5 min Non-reduced IgG: 8 min 40 – 50 min (molecule-dependent)
Detection Capability UV Absorbance at 280 nm
Fluorescence: Ex 280 nm, Em 320– 450 nm
UV Absorbance at 220 nm UV Absorbance at 220 nm Fluorescence: Ex 280 nm, Em 320-450nm
Typical Voltage Pre-focusing: 1500 V, focusing: 3000 V Separation: 5750 V Separation: 4200 V Pre-focusing: 500 V and 1000 V
Focusing: 1500 V
Sample Injections per Cartridge 100 guaranteed, 200 maximum (max 25 batches) 100 guaranteed, 500 maximum (max 25 batches) 100 guaranteed (max 25 batches) Maximum 15 injections
Maximum Sample Injections per Batch 100 48 96 1 (fractionation)
4 (cIEF)
pI/Size Range 2.85–10.45 10–270 kDa 10–270 kDa 3-10
pI/Sizing CV 1% ≤2% <2% 1%
CV for Peaks >10% Composition ≤5% (Intra-batch), ≤6% (Inter-batch) N/A N/A ≤10% (Inter-batch)
Relative Migration Time CV N/A <1% for reduced IgG <5% N/A
pI/Sizing Resolution 0.05 pI units (for wide range 3–10 ampholytes) ≥1.5 for NGHC/HC IgG Standard ≥1.0 for NGHC/HC IgG Standard N/A
Dynamic Range 2 logs 2 logs 2 logs N/A
Linearity >0.995 >0.995 >0.995 N/A
Sensitivity (LOD) 0.7 µg/mL (Native fluorescence)
3.0 µg / mL(Absorbance)
(Values based on a monoclonal antibody)
0.3 µg/mL (Value based on Internal Standard) 0.6 µg/mL (Value based on Internal Standard) N/A
Sample Tray Options 96-well plates or 48 vials 96-well plates only
Power 100 V–240 V (AC), 50/60 Hz, 500 W
Voltage Range 0–6,500 V
Temperature Control Range 4-25 °C 10-25 °C
Dimensions 44cm H x 42cm W x 61cm D
Weight 46 kg (100 lb)