Durastab Medtech Co., Ltd. has always adhered to the mission of "making diagnostic reagents more stable and more accurate" since its establishment, and is committed to providing excellent ready-to-use reagent solutions to global advanced medical diagnostic companies.
To date, Durastab has successfully provided products to over 600 companies and research teams at thousands of universities and scientific research institutions worldwide, among which are more than 50 listed IVD companies.
About Us
Search
SearchCaseiNSBlock is a casein‑based formulation specifically developed for immunoassays to eliminate nonspecific binding and reduce background, making it suitable for diagnostic kit production. This product can be applied in chemiluminescence, enzyme‑linked immunosorbent assays (ELISA), western blotting, lateral flow assays, and other detection methods.
CaseiNSBlock
CaseiNSBlock is a casein‑based formulation specifically developed for immunoassays to eliminate nonspecific binding and reduce background, making it suitable for diagnostic kit production. Compared to other forms of casein, CaseiNSBlock exhibits high solubility in biological matrices and is ideal for preparing immunoassay buffers, offering superior blocking performance on both membranes and microplates. This product can be applied in chemiluminescence, enzyme‑linked immunosorbent assays (ELISA), western blotting, lateral flow assays, and other detection methods. It can be used to block surfaces such as microspheres, polystyrene microplates, nitrocellulose membranes, or other solid supports, or formulated into a liquid blocking solution to achieve a higher signal‑to‑noise ratio and enhance the sensitivity of immunoassays.
Art no: CNBK
Package size: 100g, 250g, 500g, 1kg, bulk
pH value: 5.4 ~ 6.4 (50 mg/mL in water)
Protein Content: ≥90%
Shelf life: 1 year (2~8℃)/ 5 years (≤ -20℃)
Storage: 2-8℃/ ≤ -20℃
Application:
Western blot / ELISA/ Chemiluminescence/ Microarray/ etc.
Instruction:
For bulk packaging, it can be subdivided into smaller aliquots under clean conditions to avoid contamination risks from repeated opening of the main container.
Preparation of Blocking/Dilution/Working Solution: Weigh the required amount of CaseiNSBlock, dissolve it in the appropriate solution, adjust to the desired pH, and then use or store at 2–8 °C. Adding Tween‑20 or another surfactant at a final concentration of 0.1%–0.5% may further enhance blocking performance.
For research use only or for further use in the production of detection kits. Not for human or animal use!
Store at 2-8 °C.
For research use only or for further use in the production of detection kits. Not for human or animal use!
Q1: How do I choose a blocking buffer for ELISA?
A: Start from the assay matrix: BSA-based (BSAB) for standard systems, casein-based (CABS, 5%/10% concentrates) for strong background reduction on nitrocellulose and plates, Ultra for demanding low-background assays, and protein-free (PFBS, PFBK) when foreign proteins must be excluded.
Q2: What is the difference between active and passive blockers?
A: Passive blockers occupy free binding sites on the solid phase, while active blockers specifically neutralize interfering antibodies such as HAMA, rheumatoid factor and heterophilic antibodies in patient samples.
Q3: What is the difference between GelatiNSBlock-P and GelatiNSBlock-F?
A: They are gelatin-based blockers from different source materials (P and F), offering different background profiles; screen both if standard BSA/casein blockers leave residual non-specific signal.
Q4: How are the 5× and 10× casein blockers used?
A: Dilute the concentrate with your assay buffer to 1× before use; the concentrated format reduces shipping and storage volume for kit manufacturing.
Q5: Can blockers be used in Western blotting as well as ELISA?
A: Yes - casein and gelatin-based blockers are widely used on nitrocellulose and PVDF membranes, while the ELISA-focused blockers address microplate surfaces.
Committed to providing excellent ready-to-use reagent solutions to global advanced medical diagnostic companies.
Send RequestDurastab Medtech (Durastab IVD) is an IVD raw materials manufacturer based in Shenzhen, China, supplying ELISA and CLIA substrates, enzyme stabilizers, blocking buffers and reagent preservatives to in vitro diagnostic manufacturers worldwide.
By submitting this form,you consent to receive marketing updates from Durastab Medtech (Durastab IVD) .
