Phosphopeptide Mass Spec Standards – 1 kit

Product Name: Phosphopeptide Mass Spec Standards - 1 kit

Purity: 95%

Form: Lyophilized

Storage Conditions: - 20 °C

Research Area: Peptide Series

Source / Species: n/a

Conjugation: Unconjugated

Code Nacres: NA.26

Application: Phosphopeptide Standard Mix (6 Peptides Kit) contains six well-characterized phosphopeptides derived from biologically relevant proteins, including β-casein, protein kinase A (PKA) and protein kinase C (PKC) substrates, DAM1, and the insulin receptor kinase domain. Each phosphopeptide is individually packaged and designed for use as reference standards in LC–MS and LC–MS/MS workflows. The kit supports method development, instrument calibration, and validation of phosphopeptide enrichment strategies, enabling accurate identification and quantification of phosphorylated peptides in proteomics experiments. It is particularly valuable for researchers studying protein phosphorylation, kinase signaling networks, and quantitative phosphoproteomics, providing reliable standards for evaluating sample preparation methods and mass spectrometry performance.

Current Research: Protein phosphorylation is one of the most widespread and important post-translational modifications in cells. It regulates signaling pathways, enzyme activity, protein localization, and interactions within complex cellular networks. Because phosphorylation events often occur at low abundance and can be dynamically regulated, mass spectrometry–based phosphoproteomics has become a critical approach for identifying and quantifying phosphorylated proteins. Reliable reference materials are essential for developing and validating these analytical workflows. The Phosphopeptide Standard Mix (6 Peptides Kit) provides a set of well-characterized phosphopeptides that serve as reference standards for LC–MS and LC–MS/MS experiments. Composition of the Phosphopeptide Standard Mix This kit contains six individually packaged phosphopeptides derived from biologically relevant proteins involved in signaling and regulatory pathways. The peptides originate from well-studied phosphorylation substrates, including: β-casein, a classic model phosphoprotein frequently used in mass spectrometry calibration Protein kinase A (PKA) substrate peptides, commonly used in kinase signaling studies Protein kinase C (PKC) substrate peptides, representing phosphorylation events involved in cellular signaling pathways DAM1 complex–derived peptides, relevant to mitotic regulation and kinetochore function Insulin receptor kinase domain–derived peptides, associated with metabolic signaling pathways Because these phosphopeptides originate from diverse biological contexts, they provide a useful representation of phosphorylation events encountered in proteomic analyses. Role of Phosphopeptide Standards in Mass Spectrometry In phosphoproteomics, the detection and characterization of phosphorylated peptides can be technically challenging. Phosphorylated peptides often display low abundance, altered ionization efficiency, and variable fragmentation behavior during mass spectrometry analysis. Reference standards help researchers optimize experimental conditions and verify instrument performance. The phosphopeptides in this kit serve as known reference analytes, allowing scientists to evaluate how effectively their LC–MS systems detect and identify phosphorylation sites. By analyzing samples containing defined phosphopeptides, researchers can confirm that their instruments produce accurate mass measurements and fragmentation patterns. These standards are particularly useful for confirming that phosphorylated peptides can be reliably detected and identified in complex proteomic datasets. Applications in LC–MS Method Development One of the primary uses of the phosphopeptide standard mix is method development for liquid chromatography–mass spectrometry (LC–MS) workflows. Researchers frequently analyze the standard peptides while optimizing chromatographic conditions, ionization parameters, and MS acquisition settings. Typical uses in method development include: Evaluating retention times and chromatographic separation of phosphopeptides Testing mass spectrometer sensitivity and dynamic range Optimizing collision energies for MS/MS fragmentation Verifying phosphorylation site localization algorithms These experiments help establish robust analytical protocols before analyzing complex biological samples. Calibration and Instrument Performance Monitoring Mass spectrometry instruments require routine calibration and performance verification to ensure accurate measurements. The phosphopeptide mix provides a convenient set of known analytes that can be used to monitor system performance. By analyzing these peptides under standardized conditions, researchers can assess: Mass accuracy and calibration stability Reproducibility of peptide detection Signal intensity and sensitivity of the instrument Consistent detection of the reference peptides helps confirm that the instrument is functioning correctly before performing large-scale phosphoproteomics studies. Validation of Phosphopeptide Enrichment Strategies Because phosphorylated peptides are often present at low levels in biological samples, enrichment techniques are frequently used before mass spectrometry analysis. Common approaches include immobilized metal affinity chromatography (IMAC) and metal oxide affinity chromatography (MOAC). The phosphopeptide standard mix can be used to test and validate these enrichment strategies. Researchers may spike the standards into experimental samples and then evaluate how efficiently their enrichment method recovers phosphorylated peptides. This process helps determine whether sample preparation protocols are effective at isolating phosphopeptides without introducing bias or loss. Applications in Quantitative Phosphoproteomics Quantitative phosphoproteomics aims to measure changes in protein phosphorylation across biological conditions such as drug treatment, stress responses, or disease states. Accurate quantification requires reliable reference points and well-validated analytical methods. The phosphopeptide standard mix provides known phosphorylation targets that can be used to verify quantitative accuracy and reproducibility in LC–MS/MS workflows. These standards help ensure that observed changes in phosphorylation levels reflect true biological differences rather than technical variability. Supporting Research on Kinase Signaling Networks Protein phosphorylation is central to kinase signaling pathways, which regulate many aspects of cell physiology including growth, metabolism, and stress responses. By enabling accurate phosphopeptide detection and quantification, reference standards support studies aimed at mapping phosphorylation networks and identifying regulatory signaling events. The Phosphopeptide Standard Mix (6 Peptides Kit) provides a convenient and reliable set of reference peptides for these applications. Through its use in method development, instrument calibration, enrichment validation, and quantitative phosphoproteomics, the kit helps researchers ensure the accuracy and reliability of mass spectrometry–based phosphorylation analysis.