A5038401693- Analytical Chemistry and Chromatography
- Protein purification and stability
- Monoclonal and Polyclonal Antibodies Research
- Mass Spectrometry Techniques and Applications
- Advanced Proteomics Techniques and Applications
- Biosimilars and Bioanalytical Methods
- Pesticide Residue Analysis and Safety
- Microfluidic and Capillary Electrophoresis Applications
- HER2/EGFR in Cancer Research
- Analytical Methods in Pharmaceuticals
- Hormonal and reproductive studies
- Antibiotics Pharmacokinetics and Efficacy
- Metabolomics and Mass Spectrometry Studies
- Analytical chemistry methods development
- Growth Hormone and Insulin-like Growth Factors
- Microbial Metabolic Engineering and Bioproduction
- Viral Infectious Diseases and Gene Expression in Insects
- Amino Acid Enzymes and Metabolism
- Advanced Chemical Sensor Technologies
- Biosensors and Analytical Detection
- S100 Proteins and Annexins
- Cell death mechanisms and regulation
- Poisoning and overdose treatments
- Membrane-based Ion Separation Techniques
- Electrochemical sensors and biosensors
University of Groningen
2015-2024
University of Amsterdam
1991-1994
An LC-MS/MS-based method is described for quantitatively monitoring the in vivo deamidation of biopharmaceutical monoclonal antibody trastuzumab at a crucial position its complementarity determining region (CDR). The multiplexed LC-MS/MS assay using selected reaction (SRM) allows simultaneous quantitation five molecular species derived from after tryptic digestion: stable signature peptide (FTISADTSK), deamidation-sensitive (IYPTNGYTR), deamidated products (IYPTDGYTR and IYPTisoDGYTR),...
Two important aspects of peptide and protein quantification by LC-MS/MS, the enzymatic digestion step internal standardization approach, were systematically investigated with a small protein, salmon calcitonin, which could be analyzed both without digestion. Quantification undigested after solid-phase extraction from plasma, resulted in lower limit 10 pg/mL, while introduction tryptic step, followed signature peptide, increased this to 50 pg/mL. The sensitivity was reduced interferences...
Over the past 10 years, there has been a remarkable increase in use of LC-MS for quantitative determination proteins, and this technique can now be considered an established bioanalytical platform quantification macromolecular drugs biomarkers, next to traditional ligand-binding assays. Many researchers have contributed field helped improve both technical possibilities LC-MS-based workflows our understanding meaning results that are obtained. As tribute Bioanalysis, which published many...
Two methods have been developed and validated for the determination of free total dopamine in human plasma. They are based on solid-phase extraction analyte from matrix by covalent complexation with phenylboronic acid, followed derivatization ethylchloroformate. The derivative is quantified reversed-phase liquid chromatography a C18 column positive electrospray ionization MS/MS.The high selectivity obtained, combination stable relatively non-polar nature derivatized analyte, enables reliable...
Abstract Context Genetic variation in SHBG structure may affect estimates of sex steroid exposure by altering the affinity protein for its ligand. Consequently, free hormone calculations assuming constant binding may, certain genetic variations, lead to incorrect diagnoses if is not taken into consideration. Objective To investigate effects on calculated and measured serum testosterone (T) men. Design, setting participants Population-based sibling-pair study 999 healthy men aged 25 45 (mean,...
ObjectiveTo evaluate whether immunomodulation at start of enzyme replacement therapy induces immune tolerance to recombinant human acid alpha-glucosidase (rhGAA) in patients with classic infantile Pompe disease.Study designThree (1 cross reactive immunologic material negative, 2 positive) were treated 4 weekly doses rituximab, methotrexate, and monthly intravenous immunoglobulin 40 mg/kg/week. Antibody titers measured using enzyme-linked immunosorbent assay. Neutralizing effects on rhGAA...
The study of proteins is central to unraveling (patho)physiological processes and has contributed greatly our understanding biological systems. Corresponding studies often employ procedures enrich from their matrix using antibodies or other affinity binders coupled beads with a large surface area correspondingly high binding capacity. Striving for maximal capacity may, however, not always be required desirable, example low abundance. Here we describe simplified immunoprecipitation in 96-well...
Background: Cytarabine is an anti-tumor drug that currently under investigation for treatment in combination with other anticancer drugs the chemotherapy of leukemia. The quantitative determination cytarabine plasma challenging due to required sensitivity, its vitro instability and presence isobaric endogenous compound, cytidine. Owing polarity cytarabine, conventional chromatography cannot provide adequate separation analyte interfering compounds. A few analytical methods have been reported...
Hyperphosphorylated tau protein is well-known to be involved in the formation of neurofibrillary tangles and progression age-related neurodegenerative diseases (tauopathies), including Alzheimer's Disease (AD). Tau phosphorylated at serine-396 (pS396-tau) often linked disease progression, we therefore developed an analytical method measure pS396-tau cerebrospinal fluid (CSF) humans animal models AD. In S396-region, multiple phosphorylation sites are present, causing structural complexity...
Sex hormone binding globulin (SHBG) is a protein which plays an important role in regulating the transport and availability of biologically active androgens estradiol to target cells used calculate free testosterone concentrations.
Pertuzumab is a monoclonal antibody used for the treatment of HER2-positive breast cancer in combination with trastuzumab. Charge variants trastuzumab have been extensively described literature; however, little known about charge heterogeneity pertuzumab. Here, changes ion-exchange profile pertuzumab were evaluated by pH gradient cation-exchange chromatography after stressing it up to 3 weeks at physiological and elevated 37 °C. Isolated arising under stress conditions characterized peptide...