Research Library

Peptide science, explained with rigor

Editorial articles for qualified laboratories—chemistry, handling, analytics, and quality systems. For research and education only.

76 published articles · 4 categories

Featured

Start here

All articles

Browse the library

  • Peptide Chemistry · 24–28 min · Aug 1, 2026

    PEGylation of Peptides

    A technical guide to PEG conjugation chemistry, site-selective attachment, polymer architecture, analytical characterization, and quality control for PEG-modified peptides.

  • Analytical Testing · 12 min · Jul 31, 2026

    A Strategy for Peptide Sequence Confirmation

    How intact mass, MS/MS, peptide mapping, composition, and orthogonal methods combine to support peptide sequence identity.

  • Analytical Testing · 10 min · Jul 31, 2026

    Accuracy vs. Precision in Peptide Testing

    Why closeness to the true value differs from repeatability and how both are evaluated in analytical validation.

  • Analytical Testing · 11 min · Jul 31, 2026

    Adduct Formation in Peptide Mass Spectrometry

    How sodium, potassium, solvents, acids, and matrix components create additional peptide mass-spectral signals.

  • Peptide Chemistry · 13 min · Jul 31, 2026

    Advanced Solid-Phase Peptide Synthesis

    How difficult sequences, resin aggregation, pseudoproline building blocks, double coupling, and process monitoring improve SPPS outcomes.

  • Analytical Testing · 11 min · Jul 31, 2026

    Amino Acid Analysis for Peptide Characterization

    How hydrolysis, derivatization, separation, and detection are used to assess amino-acid composition and support peptide content.

  • Quality Assurance · 12 min · Jul 31, 2026

    Analytical Method Transfer Between Laboratories

    How laboratories demonstrate that a peptide analytical procedure performs comparably after transfer.

  • Quality Assurance · 13 min · Jul 31, 2026

    Analytical Method Validation for Peptide Testing

    An introduction to specificity, accuracy, precision, range, robustness, system suitability, and lifecycle control for peptide analytical methods.

  • Analytical Testing · 11 min · Jul 31, 2026

    Analytical Specificity for Peptide Methods

    How a method distinguishes the target peptide from impurities, degradants, excipients, and matrix components.

  • Quality Assurance · 12 min · Jul 31, 2026

    Batch-to-Batch Consistency in Peptide Manufacturing

    How specifications, process controls, trend analysis, sampling, and analytical comparability support consistent peptide batches.

  • Quality Assurance · 10 min · Jul 31, 2026

    Chain of Custody for Peptide Samples

    How receipt, labeling, transfer, storage, and disposition records protect sample identity and test credibility.

  • Analytical Testing · 11 min · Jul 31, 2026

    Chromatographic Resolution Explained

    How resolution describes separation between peptide peaks and how selectivity, efficiency, and retention influence it.

  • Analytical Testing · 12 min · Jul 31, 2026

    Chromatography Fundamentals for Peptide Analysis

    A foundational guide to retention, selectivity, efficiency, resolution, mobile phase, and stationary phase behavior in peptide chromatography.

  • Storage & Handling · 12 min · Jul 31, 2026

    Cold-Chain Logistics for Research Peptides

    How packaging qualification, temperature logging, lane risk, and excursion assessment protect temperature-sensitive peptide shipments.

  • Storage & Handling · 12 min · Jul 31, 2026

    Container-Closure Systems for Peptide Materials

    How vials, stoppers, seals, permeability, extractables, and surface interactions affect peptide stability.

  • Quality Assurance · 13 min · Jul 31, 2026

    Data Integrity in Peptide Testing Laboratories

    How audit trails, controlled access, raw-data review, and documented processing protect analytical reliability.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Deamidation and Isomerization in Peptides

    How asparagine and glutamine can undergo deamidation and how aspartate residues can form isoaspartate.

  • Analytical Testing · 11 min · Jul 31, 2026

    Detector Linearity in Peptide Analysis

    How analytical response should relate to concentration and why residuals, weighting, and range matter more than correlation alone.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Disulfide Bonds in Peptide Chemistry

    How cysteine pairing, oxidation, reduction, scrambling, and analytical mapping affect disulfide-containing peptides.

  • Quality Assurance · 11 min · Jul 31, 2026

    Elemental Impurity Testing for Peptide Materials

    How elemental impurities may enter peptide materials and how ICP-MS or ICP-OES can support risk-based control.

  • Quality Assurance · 10 min · Jul 31, 2026

    Endotoxin Testing vs. Sterility Testing

    Why endotoxin and sterility are different quality attributes, how each is tested, and why one result cannot substitute for the other.

  • Quality Assurance · 12 min · Jul 31, 2026

    Environmental Monitoring in Controlled Laboratories

    How viable, nonviable, surface, and facility data support contamination control in controlled laboratory environments.

  • Quality Assurance · 12 min · Jul 31, 2026

    Forced Degradation Studies for Peptides

    How controlled stress studies reveal degradation pathways and demonstrate stability-indicating analytical methods.

  • Quality Assurance · 11 min · Jul 31, 2026

    Good Laboratory Practice Principles

    An educational overview of GLP roles, study plans, raw data, quality assurance, and archival control.

  • Storage & Handling · 11 min · Jul 31, 2026

    How to Assess Temperature Excursions

    A structured approach to evaluating time-temperature events affecting stored or shipped peptide materials.

  • Analytical Testing · 11 min · Jul 31, 2026

    How to Interpret a Peptide HPLC Chromatogram

    A practical guide to chromatogram axes, retention time, peak area, resolution, integration, system suitability, and common artifacts.

  • Analytical Testing · 12 min · Jul 31, 2026

    How to Investigate an Unknown HPLC Peak

    An evidence-based workflow for characterizing new or unexpected peaks in peptide testing.

  • Analytical Testing · 12 min · Jul 31, 2026

    How to Read a Peptide Certificate of Analysis

    A field-by-field guide to peptide COAs, including identity, purity, assay, method details, specifications, signatures, and common warning signs.

  • Storage & Handling · 10 min · Jul 31, 2026

    How to Store Lyophilized Research Peptides

    A laboratory-focused guide to temperature, moisture, oxygen, light, packaging, and stability documentation for dry peptide materials.

  • Quality Assurance · 10 min · Jul 31, 2026

    How to Verify a Certificate of Analysis

    A practical process for confirming COA authenticity, batch linkage, laboratory identity, and report traceability.

  • Analytical Testing · 14 min · Jul 31, 2026

    HPLC Method Development for Peptide Analysis

    A structured approach to defining method goals, screening columns, optimizing gradients, and resolving critical peptide impurities.

  • Analytical Testing · 13 min · Jul 31, 2026

    HPLC Peptide Purity Testing Explained

    How reversed-phase HPLC separates peptide components, how chromatographic purity is calculated, and why method suitability matters.

  • Peptide Chemistry · 11 min · Jul 31, 2026

    Hydrolysis and Peptide-Bond Cleavage

    How water, pH, sequence, and temperature contribute to peptide-bond and side-chain hydrolysis.

  • Quality Assurance · 12 min · Jul 31, 2026

    Instrument Calibration and Qualification in Peptide Testing

    How installation, operational, performance, and routine calibration controls support reliable analytical data.

  • Quality Assurance · 12 min · Jul 31, 2026

    ISO/IEC 17025 and Laboratory Competence

    How ISO/IEC 17025 addresses impartiality, competence, traceability, validation, and reporting in testing laboratories.

  • Analytical Testing · 11 min · Jul 31, 2026

    Isotopic Distributions in Peptide Mass Spectrometry

    How natural isotopes create peptide isotope envelopes and how monoisotopic and average masses differ.

  • Quality Assurance · 12 min · Jul 31, 2026

    Laboratory Audits for Peptide Testing

    What to evaluate when auditing third-party peptide testing laboratories, including scope, methods, records, and data integrity.

  • Quality Assurance · 11 min · Jul 31, 2026

    Laboratory Document Control

    How SOP approval, versioning, training, obsolescence, and record retention prevent uncontrolled laboratory practices.

  • Analytical Testing · 12 min · Jul 31, 2026

    LC-MS vs. MALDI-TOF for Peptide Characterization

    How LC-MS and MALDI-TOF differ in ionization, workflow, quantitation, impurity profiling, throughput, and peptide identity testing.

  • Analytical Testing · 12 min · Jul 31, 2026

    Limit of Detection and Limit of Quantitation

    How LOD and LOQ are established for peptide methods and why visual detection is different from reliable quantitation.

  • Analytical Testing · 10 min · Jul 31, 2026

    Mass Accuracy in Peptide Mass Spectrometry

    How calibration, resolution, charge assignment, and processing affect the difference between observed and theoretical peptide mass.

  • Analytical Testing · 11 min · Jul 31, 2026

    Mass Deconvolution in Peptide Analysis

    How software converts multiply charged peptide spectra into neutral-mass results and where processing errors can occur.

  • Analytical Testing · 12 min · Jul 31, 2026

    Mass Spectrometry for Peptide Identity

    How peptide mass spectrometry works, how charge states are interpreted, and what intact mass can and cannot prove.

  • Quality Assurance · 12 min · Jul 31, 2026

    Measurement Uncertainty in Peptide Testing

    How uncertainty components influence confidence in assay, impurity, and quantitative peptide results.

  • Analytical Testing · 12 min · Jul 31, 2026

    MS/MS Fragmentation of Peptides

    How peptide ions fragment in tandem mass spectrometry and how product-ion series support sequence interpretation.

  • Peptide Chemistry · 11 min · Jul 31, 2026

    N-Terminal and C-Terminal Peptide Modifications

    How acetylation, amidation, pyroglutamate formation, and terminal chemistry affect mass, charge, and stability.

  • Quality Assurance · 13 min · Jul 31, 2026

    Out-of-Specification and Atypical Laboratory Results

    How laboratories investigate failing, atypical, and out-of-trend peptide test results without testing into compliance.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Oxidation Pathways in Peptides

    How oxygen, light, metals, peroxides, and formulation conditions can oxidize susceptible peptide residues.

  • Analytical Testing · 11 min · Jul 31, 2026

    Peak Integration in HPLC

    How chromatographic software defines peak boundaries and why controlled integration is essential for credible peptide purity results.

  • Analytical Testing · 11 min · Jul 31, 2026

    Peak Tailing and Fronting in Peptide HPLC

    Why chromatographic peaks become asymmetric and how overload, secondary interactions, and system effects alter peptide results.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Peptide Aggregation and Self-Association

    Why peptides aggregate, how concentration and interfaces contribute, and which analytical methods can detect self-association.

  • Analytical Testing · 11 min · Jul 31, 2026

    Peptide Charge States in Electrospray Mass Spectrometry

    Why peptides form multiple charged ions and how charge-state assignment supports deconvolution and mass confirmation.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Peptide Counterions and Salt Forms

    Why acetate, trifluoroacetate, chloride, and other counterions matter for mass, solubility, pH, and analytical interpretation.

  • Peptide Chemistry · 13 min · Jul 31, 2026

    Peptide Coupling Chemistry

    How carboxyl activation, coupling reagents, bases, and reaction conditions influence peptide-bond formation and side reactions.

  • Analytical Testing · 12 min · Jul 31, 2026

    Peptide Mapping Explained

    How enzymatic or chemical digestion and chromatographic analysis create a peptide fingerprint for identity and structural comparison.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Peptide Solubility Fundamentals

    How charge, hydrophobicity, pH, ionic strength, concentration, and temperature influence peptide dissolution.

  • Storage & Handling · 11 min · Jul 31, 2026

    Photostability of Peptide Materials

    How ultraviolet and visible light can affect peptide structure, packaging, and stability testing.

  • Quality Assurance · 11 min · Jul 31, 2026

    Proficiency Testing and Interlaboratory Comparisons

    How external comparisons evaluate laboratory performance and reveal method or execution differences.

  • Peptide Chemistry · 12 min · Jul 31, 2026

    Protecting Groups in Peptide Synthesis

    Why temporary and side-chain protecting groups are required and how orthogonal chemistry prevents uncontrolled reactions.

  • Quality Assurance · 13 min · Jul 31, 2026

    Quality Systems in Peptide Manufacturing

    How document control, deviations, CAPA, change control, supplier qualification, and data integrity support peptide quality.

  • Analytical Testing · 11 min · Jul 31, 2026

    Recovery Studies in Peptide Analysis

    How spike-recovery and process-recovery experiments reveal losses from extraction, adsorption, filtration, and matrix effects.

  • Quality Assurance · 12 min · Jul 31, 2026

    Reference Standards in Peptide Analysis

    How peptide reference standards are qualified, assigned, stored, tracked, and used for identity and quantitative testing.

  • Storage & Handling · 12 min · Jul 31, 2026

    Research Peptide Reconstitution: Laboratory Principles and Controls

    A research-only overview of diluent compatibility, concentration calculations, aseptic handling, mixing, labeling, and post-reconstitution stability.

  • Quality Assurance · 11 min · Jul 31, 2026

    Residual Solvent Testing in Peptide Manufacturing

    How synthesis and purification solvents are controlled using risk-based specifications and gas chromatographic analysis.

  • Peptide Chemistry · 11 min · Jul 31, 2026

    Resin Selection in Solid-Phase Peptide Synthesis

    How linker chemistry, loading, swelling, and support properties influence peptide assembly and final C-terminal form.

  • Analytical Testing · 11 min · Jul 31, 2026

    Robustness Testing for Peptide Methods

    How deliberate small method changes identify critical parameters and operating ranges in peptide analysis.

  • Analytical Testing · 10 min · Jul 31, 2026

    Ruggedness and Intermediate Precision

    How analysts, instruments, days, columns, and laboratories contribute to real-world method variability.

  • Analytical Testing · 12 min · Jul 31, 2026

    Sample Preparation for Peptide Analysis

    How dissolution, dilution, filtration, adsorption, stability, and container selection influence analytical results.

  • Analytical Testing · 10 min · Jul 31, 2026

    Signal-to-Noise in Chromatographic Testing

    How baseline noise and analyte signal affect sensitivity, detection limits, and low-level peptide impurity measurements.

  • Peptide Chemistry · 11 min · Jul 31, 2026

    Solid-Phase Peptide Synthesis Explained

    How resin-based peptide assembly works, why protecting groups are required, and where synthesis-related impurities originate.

  • Analytical Testing · 12 min · Jul 31, 2026

    System Suitability Testing for Peptide Methods

    How system-suitability criteria verify that an HPLC or LC-MS system is ready to generate acceptable peptide data.

  • Peptide Chemistry · 14 min · Jul 31, 2026

    The Complete Guide to Peptide Chemistry

    A technical introduction to peptide structure, amino-acid sequence, peptide bonds, synthesis, purification, stability, and analytical characterization.

  • Analytical Testing · 11 min · Jul 31, 2026

    UPLC vs. HPLC for Peptide Analysis

    A practical comparison of HPLC and UPLC for peptide purity, impurity profiling, transfer, speed, pressure, and method performance.

  • Analytical Testing · 10 min · Jul 31, 2026

    UV Detection in Peptide HPLC

    How peptide bonds and aromatic residues absorb ultraviolet light and how wavelength selection affects sensitivity and impurity response.

  • Storage & Handling · 11 min · Jul 31, 2026

    Water Content and Karl Fischer Testing

    Why residual moisture matters in lyophilized peptides and how Karl Fischer titration differs from loss on drying.

  • Quality Assurance · 11 min · Jul 31, 2026

    What Makes an Analytical Method Stability-Indicating?

    How specificity, stress studies, mass balance, impurity resolution, and lifecycle controls establish stability-indicating capability.