Accelerating the Pace of Discovery

FIX&PERM® Cell Fixation and Permeabilization Kits and Reagents

Intracellular staining of protein biomarkers using antibodies in flow cytometry has opened diverse new pathways for phenotypic and functional characterization of cells in both research and clinical diagnosis.

Definitive phenotypic identification of certain cell types can require labeling of both cell surface and intracellular markers. Additionally, the cytoplasmic localization of typical membrane molecules can prove to be a most reliable lineage marker, such as cytoplasmic CD3 and CD22 in undifferentiated leukemia.

In such cases, and for many other cell biological and functional investigations, intracellular immunostaining is a necessity. For this purpose, we offer an industry-leading cell fixation and permeabilization kit – FIX&PERM® – which offers several advantages over other methods for intracellular staining of cells in flow cytometry.

FIX&PERM® is a simple flow cytometry cell preparation procedure making use of two reagents. Reagent A gently fixes cells, while Reagent B permeabilizes them. The specific formulations reduce background and allow simultaneous addition of permeabilization medium and fluorochrome-labeled antibodies, allowing staining of extracellular surface markers and intracellular structures such as cytoplasmic enzymes, nuclear proteins, oncoproteins, cytokines and immunoglobulins.

FIX&PERM® Kit Advantages

  • Mildly fixes cells, preserving their flow cytometric scatter characteristics
  • Allows simultaneous characterization of both intracellular and cell surface markers
  • Rapid technique – whole procedure can be carried out in less than one hour, ready for immediate analysis or storage for 24 hours
  • Proven technology – initially characterized in Knapp et al. in 1994, independently validated in studies such as Groeneveld et al. in 1996 and Lanza et al. in 1997, and cited in hundreds of peer-reviewed publications since
  • Stringent QC procedures – the quality of each lot is confirmed using well-defined blood samples and subsequent comparison of scatter characteristics and immunostaining patterns, ensuring consistent and reliable results each time
  • Stable – our formulations do not contain volatile organic solvents, enabling storage at ambient temperature during shipment and in laboratories
  • Flexible – can be used with most monoclonal antibody conjugates, as well as our range of antibodies with optimized protocols for use with FIX&PERM®
  • CE/IVD registered kits available for European customers in a clinical laboratory setting (contact us for further information)

FIX&PERM® Products

Code Name Product Type Clone
GAS-002 FIX&PERM® Cell Fixation and Permeabilization Kit Buffers and Reagents
GAS-002-1 FIX&PERM® Kit 1000 Buffers and Reagents
GAS-002A-1 FIX&PERM® Solution A (Fix) Buffers and Reagents
GAS-002B-1 FIX&PERM® Solution B (Perm) Buffers and Reagents
GAS-002M FIX&PERM® Sample Kit Buffers and Reagents

FIX&PERM® Procedure

For each sample to be analyzed use 50 µl of whole blood, bone marrow or mononuclear cell suspension in a 5 ml tube
  • Add 100 µl of Reagent A (Fixation Medium, stored and used at room temperature)
  • Incubate for 15 minutes at room temperature
  • Add 5 ml phosphate buffered saline and centrifuge cells for 5 minutes at 300 g
  • Remove supernatant and add to cell pellet 100 µl Reagent B (Permeabilization Medium) and 20 µl of the appropriate monoclonal antibody conjugate
  • Vortex at low speed for 1-2 seconds
  • Incubate for 15 minutes at room temperature
  • Wash cells with phosphate buffered saline as described above
  • Remove supernatant and resuspend cells in sheath fluid for immediate analysis or resuspend cells in 0.5 ml 1.0 % formaldehyde and store at 2-8°C in the dark
  • Analyze fixed cells within 24 hours

Products optimized for use with FIX&PERM®

The majority of available monoclonal antibody conjugates can be used with FIX&PERM®. However, in some cases the fixation step may have to be optimized. We offer a number of mouse anti-human conjugated (PE/FITC) monoclonal antibodies optimized for use with FIX&PERM®.
Antigen Clone Isotype Format Quantity Cat. No.
CD3 UCHT1 IgG1 Purified 0.2 mg GM-4011
FITC-labeled 100 tests GM-4012
PE-labeled 100 tests GM-4013
CD22 RFB4 IgG1 Purified 0.2 mg GM-4051
FITC-labeled 100 tests GM-4052
PE-labeled 100 tests GM-4053
Lactoferrin 4C5 IgG1 Purified 0.2 mg GM-4111
PE-labeled 100 tests GM-4113
Myeloperoxidase 8E6 IgG1 Purified 0.2 mg GM-4191
(MPO-C2) FITC-labeled 100 tests GM-4192
PE-labeled 100 tests GM-4193
Lysozyme LZ-2 IgG1 Purified 0.2 mg GM-4131
FITC-labeled 100 tests GM-4132
CD68 Ki-M7 IgG1 FITC-labeled 100 tests GM-4152
Furthermore, a number of Combi panels are offered for dual immunostaining protocols.
Antigen Clone Isotype Format Quantity Cat. No.
Negative control Vl-AP IgG1 FITC-labeled 50 tests GIC-201
Vl-AP IgG1 PE-labeled -
Lysozyme LZ-2 IgG1 FITC-labeled 50 tests GIC-206
Lactoferrin 4C5 IgG1 PE-labeled -
Myeloperoxidase 8E6 IgG1 FITC-labeled 50 tests GIC-212
Lactoferrin 4C5 IgG1 PE-labeled -
Myeloperoxidase 8E6 IgG1 FITC-labeled 50 tests GIC-213
CD3 UCHT1 IgG1 PE-labeled -
Myeloperoxidase 8E6 IgG1 FITC-labeled 50 tests GIC-214
CD22 RFB4 IgG1 PE-labeled