PBS Blocking Buffer with Casein (1%)
FluxMPS™ PBS Blocking Buffer with Casein (1%)
An MPS-grade phosphate buffered saline blocking reagent formulated with 1% purified casein at a precise, stable pH of 7.4. Quadruple-stage filtered — 0.1-micron membrane filtered twice and 0.04-micron membrane filtered twice — for ultra-clean, microchannel-safe performance in Western blotting, ELISA, immunohistochemistry, and chip-based immunoassay workflows.
- World’s cleanest buffer for all cell and molecular biology experiments
- Quadruple-stage filtration: 0.1-micron membrane filtered twice and 0.04-micron membrane filtered twice
- Precise, stable pH of 7.4 supports antibody and protein integrity throughout immunoassay protocols
- 1% purified casein blocking agent minimizes non-specific binding with lower background than milk-based blockers in biotin-avidin systems
- DNase- and RNase-tested: no activity detected after 18-hour incubation at room temperature
- Manufactured under ISO 13485-certified, CE-approved facilities with final QC at the Diagnocine R&D and Quality Testing Center
- Sterile, opaque liquid supplied ready for use from long-term -20°C storage
- Customizable concentration, pH, and additive package available on request
- pH7.4
- AppearanceOpaque Liquid
- Casein Content1%
- Buffer BasePhosphate Buffered Saline (PBS)
- FiltrationQuadruple-stage (0.1 µm x2, 0.04 µm x2)
- DNase ActivityNone Detected
- RNase ActivityNone Detected
- Storage-20°C, Long Term
- Shelf Life1 Year
- ManufacturingISO 13485-Certified, CE-Approved
Engineered where standard blocking buffers fail
Conventional 0.22 µm-filtered blocking buffers can carry subvisible particulates, inconsistent pH, and higher assay background — especially in biotin-avidin detection systems where milk-based blockers introduce endogenous biotin interference. FluxMPS™ PBS Blocking Buffer with Casein (1%) is built to remove those variables at the source.
Microchannel-safe purity
A final 0.04 µm filtration pass supports clean performance in narrow microfluidic channels and chip-based immunoassay formats.
Precise, stable pH
Buffered to pH 7.4 with defined PBS salt concentrations, preserving protein and antibody integrity throughout the blocking step.
Ultrapure-grade water
Formulated with Type 1 water (18.2 MΩ·cm), consistent with USP <85> water quality expectations.
Low background for imaging & assays
Single-protein casein blocking reduces cross-reactivity versus serum or milk, giving lower background in biotin-avidin and fluorescence-based detection.
Defined, traceable composition
Every PBS salt and the casein blocking protein is listed with concentration, plus lot-level DNase/RNase testing.
Customization on demand
Concentration, pH, and additive modifications available — contact support@diagnocine.com.
Quadruple-stage filtration system
DCP-CPBS1X is sterile, ultrapure, and filtered through a 0.1-micron membrane twice and a 0.04-micron membrane twice, giving the buffer a level of particulate control suited to sensitive immunoassays and microfluidic immunoassay chips.
-
1
0.1 µm Pre-filtration I
First 0.1 µm pass removes larger particulates and aggregates, protecting downstream filters.
-
2
0.04 µm Pre-filtration II
First 0.04 µm pass retains finer particulates and bioburden ahead of the final sterile passes.
-
3
0.1 µm Sterile-filtration I
Second 0.1 µm pass provides redundant particulate and bioburden reduction.
-
4
0.04 µm Sterile-filtration II — Final Polish
Second 0.04 µm pass is the final polish; the smallest known mycoplasma species are approximately 0.2 microns, well above this filtration threshold, helping prevent mycoplasma contamination.
Performance vs. conventional buffer
Sequential 0.1 µm and 0.04 µm filtration, each applied twice, removes finer particulates than a single 0.22 µm pass used in conventional blocking buffers.
© Diagnocine® — DCP-CPBS1X
Where DCP-CPBS1X is used
A casein-based blocking buffer for immunoassay, chip-based, and imaging workflows where non-specific binding must be minimized without introducing cross-reactivity.
Automated Bioreactors & Robotics
An optional 0.01 µm (10 nm) ultra-filtered variant of this blocking buffer can be produced for fully automated bioreactor and robotic liquid-handling platforms where valve and sensor protection is critical.
- Total Particulate Exclusion
- Valve & Sensor Protection
- Extended Perfusion Stability
Inquiry Required: the 0.01 µm ultra-filtered grade is produced to order — contact support@diagnocine.com to request it.
Micro Physiological System (MPS) & Chip
Compatible with blocking steps in chip-based immunoassay and biosensor formats.
Wash, Dilution & Reconstitution
The PBS base supports washing steps between blocking and antibody incubation.
iPSC-Derived Model Handling
Blocks non-specific antibody binding in immunocytochemistry of iPSC-derived cell models.
Endothelial & Primary Cell Perfusion
Low-background blocking supports immunostaining of endothelial and primary cell cultures.
ELISA, Blotting & Blocking
Blocks non-specific binding sites on membranes and microplates, enhancing specificity and sensitivity; recommended for biotin-avidin complex assays over milk-based blockers.
Microscopy & Optical Sensing
Lower background than milk-based blockers supports cleaner fluorescence-based imaging.
Specifications at a glance
Values below reflect DCP-CPBS1X as described in its formulation and quality control records.
| Parameter | Specification |
|---|---|
| Formulation / Composition | Phosphate Buffered Saline with 1% purified casein USP <791> |
| Appearance | Opaque Liquid |
| pH | 7.4 |
| Parameter | Specification |
|---|---|
| Sterility USP <71> | Filtered 0.1-micron membrane twice and 0.04-micron membrane twice |
| DNase Activity | None detected (18 hr, plasmid DNA, room temperature) |
| RNase Activity | None detected (18 hr, ribosomal RNA, room temperature) |
| Water Quality | Ultrapure Type 1 water (18.2 MΩ·cm) |
| Manufacturing Standard ISO 13485 | ISO 13485-certified, CE-approved facility |
| Parameter | Specification |
|---|---|
| Storage Temperature | -20°C, Long Term |
| Shelf Life | 1 Year |
| Pre-Use Equilibration | Bring to room temperature or 37°C before use to minimize temperature-induced variables |
| Parameter | Specification |
|---|---|
| Raw Material Grade | Purified, casein blocking protein |
| Manufacturing QMS | ISO 13485-certified, CE-approved facility (Diagnocine Precision suppliers) |
| Production Method | Final packaging, QA, and testing at the Diagnocine R&D and Quality Testing Center; customization and assembly at Diagnocine Precision, Totowa, New Jersey, USA |
| Intended Use | Research Use Only (RUO) |
Full composition
All components and concentrations below are reproduced exactly from the product formulation record.
| Component | CAS Number | Concentration |
|---|---|---|
| Casein | 9000-71-9 | 1% |
| Sodium Chloride | 7647-14-5 | 137 mM |
| Potassium Chloride | 7447-40-7 | 2.7 mM |
| Sodium Phosphate Dibasic Anhydrous (Na2HPO4) | 7558-79-4 | 10.1 mM |
| Potassium Phosphate Monobasic Anhydrous (KH2PO4) | 7778-77-0 | 1.76 mM |
Manufacturing & compliance
DCP-CPBS1X is manufactured, quality-tested, and packaged under a controlled quality system.
ISO 13485:2016 QMS
Manufactured under ISO 13485-certified and CE-approved facilities.
Ultrapure Type 1 Water
Formulated with Type 1 water (18.2 MΩ·cm).
ISO Class 5 Fill & Finish
Final packaging and QA performed at the Diagnocine R&D and Quality Testing Center.
Micro-Batch Precision
Customization and assembly completed at Diagnocine Precision, Totowa, New Jersey, USA.
DNase Activity Tested
None detected after incubation of plasmid DNA with this product for 18 hours at room temperature.
RNase Activity Tested
No RNase activity detected after incubation of ribosomal RNA with this product for 18 hours at room temperature.
Sterility USP <71>
Filtered 0.1-micron membrane twice and 0.04-micron membrane twice.
Documentation / CoA
Certificate of Analysis available on request.
How DCP-CPBS1X compares
A side-by-side look at DCP-CPBS1X versus conventional casein and milk-based blocking buffers.
| Parameter | DCP-CPBS1X (FluxMPS™) | Conventional Casein Buffer | Milk-Based Blocking Buffer |
|---|---|---|---|
| Blocking Agent | Purified Casein, 1% | Casein, unspecified purity | Non-fat dry milk |
| Final Filtration Pore Size | 0.04 µm | Not specified | 0.22 µm |
| Number of Filtration Stages | 4 | Not specified | 1 |
| DNase / RNase Tested | check_circle | cancel | cancel |
| pH Defined & QC-Verified | check_circle 7.4 | cancel | cancel |
| Ultrapure Type 1 Water | check_circle | cancel | cancel |
| ISO 13485 Manufacturing | check_circle | cancel | cancel |
| Low Background in Biotin-Avidin Assays | check_circle | check_circle | cancel |
| Microfluidic Channel Compatibility | check_circle | cancel | cancel |
| Custom Formulation Available | check_circle | cancel | cancel |
Frequently asked questions
Common questions about DCP-CPBS1X PBS Blocking Buffer with Casein (1%).
Supporting literature
Curated references supporting the use of casein-based blocking buffers, PBS chemistry, and filtration control in immunoassay and microfluidic workflows.
- Engvall E, Perlmann P. Enzyme-linked immunosorbent assay (ELISA): quantitative assay of immunoglobulin G. Immunochemistry. 1971. doi:10.1016/0019-2791(71)90454-X
- Renart J, Reiser J, Stark GR. Transfer of proteins from gels to diazobenzyloxymethyl-paper and detection with antisera. Proc Natl Acad Sci USA. 1979. doi:10.1073/pnas.76.7.3116
- Bordeaux J, Welsh A, Agarwal S, et al. Antibody validation. BioTechniques. 2010. doi:10.2144/000113382
- Steinberg TH, Jones LJ, Haugland RP, Singer VL. Fluorescence-based western blot and blocking chemistry considerations. Anal Biochem. 1996. doi:10.1006/abio.1996.0230
- Wilchek M, Bayer EA. The avidin-biotin complex in bioanalytical applications. Anal Biochem. 1988. doi:10.1016/0003-2697(88)90090-7
- Ramsden JJ. Puzzles and paradoxes in protein adsorption and blocking chemistry. Chem Soc Rev. 1995. doi:10.1039/CS9952400073
- Bhatia SN, Ingber DE. Microfluidic organs-on-chips. Nat Biotechnol. 2014. doi:10.1038/nbt.2989
- Sackmann EK, Fulton AL, Beebe DJ. The present and future role of microfluidics in biomedical research. Nature. 2014. doi:10.1038/nature13118
- Williams KL. Endotoxins: Pyrogens, LAL Testing and Depyrogenation. CRC Press reference chemistry chapter on reagent purity control. 2007. doi:10.1201/9781420020595
