Endogenous interfering proteins can be found in any biological matrix, plasma, serum, whole blood, urine, cerebrospinal fluid, oral fluid, sputum, synovial fluid, etc. Many bioanalytical methods to detect analytes in these fluids are based on the interaction of a binding pair, such as an antibody and its antigen or a receptor and its ligand. An interfering protein is any protein that blocks the specific interaction of the binding pair, causing false negative or false positive reactions.
The simplest approach is to irreversibly extract or scavenge the interfering endogenous proteins prior to running the IM or PK assay. The NIDS® NPX4000 Interfering Protein Extraction and Removal Kits enable the irreversible removal of these interfering endogenous proteins without affecting the detection of ADAs in an IM assay or drug molecules in a PK assay. By attaching your specific blocking antibody or binder to activated nanoparticles and pretreating the sample with these functionalized nanoparticles which will bind the interfering proteins, this simple and easy-to-use protein extraction and removal kit can cleanly sequester such interfering proteins via a centrifugation step. As a result, more than 99% of the interfering proteins or drug target can be removed, while using significantly less blocking antibody or binder than any other conventional blocking methods.
Our NIDS® nanoparticle based universal protein extraction kits exhibit the following advantages:
1. Smaller diameter, greater surface area compared to micron-size magnetic particles which are the current particles of choice. Extraction efficiency and capacity are significantly enhanced. Up to 1 µg/mL of endogenous interfering protein can be removed.
2. Binding agents are optimally oriented. The binding agents are attached using our NIDS® chemistry which employs proprietary linkers that orient the binding sites outwardly to capture their targets most efficiently. Other particle-coating chemistries will not work as well.
3. Less binding agent used. As much as 100-fold less of scavenging agents such as antibodies is required.
4. Easy to use procedure. Optimal loading and particle usage are easily calculated.
5. Flexible universal platform. Any protein or nucleic acid can be coated onto our nanoparticles. The customer can choose from a list of binding agents for 140 different endogenous proteins currently available or provide their own binding agents for attachment to the extraction nanoparticles.
Bioanalytical methods such as diagnostic, pharmacokinetic, pharmacodynamic, and immunogenicity assays have shown improved accuracy and sensitivity after sample pretreatment using these innovative extraction nanoparticles linked to target-specific off-the-shelf binding reagents such as antibodies. Our NIDS®nanoparticle based protein extraction kits are currently being used by leading biopharmaceutical companies in various stages of drug development.