Thermo Fisher Proteins & Peptides: Protein Biology Reagents, Purification & Peptide Synthesis

Whether you quantify lysates, purify tagged proteins, visualize blots, or prepare peptides for LC-MS, Thermo Fisher offers end-to-end tools under well-known lines such as Pierce™ and Invitrogen™. On this page you’ll find structured guidance, quick comparisons, and featured product families; Iright, as an authorized distributor, can source a wide range of Thermo Fisher items for your lab.

Shop by Core Categories: Assays, Western, Purification, Crosslinkers, MS Prep & Peptides

Use the overview below to jump straight to what you need. Each category summarizes typical use cases and common choices so you can decide faster. Internal links from this section can map to deeper sub-collections (e.g., BCA vs. Bradford or Ni-NTA vs. Co-NTA) if you want to expand content later.

• Protein Quantification & Stains — BCA and Bradford assay kits, UV-compatible options, Coomassie blue stains, protein standards/markers.

• Electrophoresis & Western Blot — Precast gels (Bis-Tris, Tris-Glycine), running/transfer buffers, PVDF/nitrocellulose membranes, chemiluminescent substrates, protein ladders.

• Affinity Purification — His-tag (Ni-NTA/Co-NTA), Protein A/G for IgG, magnetic beads and column resins, gentle elution buffers.

• Crosslinking & Labeling — NHS-ester and maleimide chemistries, zero-length crosslinkers, biotinylation and fluorescent labeling kits.

• Sample Prep for LC-MS — Reduction/alkylation reagents, trypsin/Lys-C digestion kits, desalting spin columns/plates, LC-MS-grade solvents.

• Peptides — Reference/standard peptides, modified peptides (phospho/acetyl/biotin/fluorescent), and custom peptide synthesis with QC documentation.

Popular Workflows: Western Blot, Co-IP/Pull-Down, and LC-MS Sample Prep

Selecting products by workflow reduces guesswork and avoids incompatibilities. The quick paths below pair typical steps with representative product families, so you can assemble a validated stack for your protocol and budget without retracing fundamentals every time.

Western Blot (WB) workflow

1. Lysis & protection: mild or strong lysis buffers with protease/phosphatase inhibitors.

2. Quantification: BCA or Bradford to normalize loading.

3. Electrophoresis: choose Bis-Tris or Tris-Glycine gels matched to your target size range.

4. Transfer: PVDF or nitrocellulose membranes; consider pore size vs. protein MW.

5. Detection: ECL chemiluminescent substrates aligned to your signal needs (standard vs. high sensitivity).

Co-IP / Pull-Down workflow

1. Pre-clear & capture: magnetic or agarose beads coupled to Protein A/G or your ligand.

2. Wash & elute: salt/Detergent-tuned buffers; gentle elution for complex stability.

3. Downstream analysis: SDS-PAGE + WB or LC-MS.

LC-MS proteomics workflow

1. Denature/Reduce/Alkylate: consistent disulfide handling to improve peptide coverage.

2. Digest: sequencing-grade trypsin or Lys-C at defined ratios/timepoints.

3. Desalt & concentrate: spin columns or plates compatible with your solvent system.

4. Analyze: LC-MS-grade solvents to minimize background and ion suppression.

Compare Key Options: BCA vs Bradford, Ni-NTA vs Co-NTA, Protein A vs G, Gel Systems

When multiple “good” choices exist, a crisp comparison helps you pick the best one for your sample and readout. Use the tables as a reference, then link to deeper pages if you want exhaustive detail or application notes.

Protein quantification at a glance

His-tag purification resins

Protein A vs Protein G for IgG

Precast gel systems

Peptides Essentials: Standards, Custom Peptide Synthesis & Common Modifications

Peptides support method development, assay calibration, and mechanism studies. You can buy ready-to-ship standards or request custom sequences with defined purity and documentation. Plan purity and modifications up front to avoid project drift and repeat orders later.

• Reference/standard peptides: use for LC-MS calibration, retention-time alignment, or method verification.

• Custom peptide synthesis: specify sequence, length, scale (mg to g), and target purity (desalted/HPLC-purified).

• Common modifications: phosphorylation, acetylation, biotinylation, fluorescent labeling (FITC, TAMRA), amidation, and lipidation.

• QC documentation: MS and HPLC chromatograms, COA; optional amino acid analysis on request.

• Dissolution guidance: match solvent to hydrophobicity (water, 0.1% TFA, 10–50% acetonitrile, or DMSO seed), then dilute into assay buffer.

Compatibility & Validation: Buffer/Detergent Tolerance, QC (HPLC/MS/COA) & Data

Method success depends on reagent compatibility and lot-to-lot consistency. Wherever possible, choose kits and consumables validated together and review the IFU/SDS for tolerance to detergents, salts, and reducing agents. Keep a simple “compatibility sheet” in your lab notebook for rapid checks.

• Buffer/detergent tolerance: confirm BCA/Bradford compatibility with your lysis buffer; check crosslinkers for amine- or sulfhydryl-reactivity in the presence of Tris/DTT.

• QC practice: prefer reagents with batch-level certificates and stated performance ranges; for peptides, keep MS/HPLC traces on file with receipt dates.

• Data continuity: record gel system, membrane type, antibody lot, and substrate when optimizing WB so you can reproduce signal levels across runs.

Featured Products: High-Demand Families in Assays, Western, Purification & Peptides

Below are representative product families that consistently map to common purchase intents. To guarantee accuracy, insert model names/SKUs only after you verify them against the Thermo Fisher website; we deliberately omit numbers here to meet your “SKUs must be correct” standard.

• BCA Protein Assay Kits — microplate and tube formats; broad linear range; compatible with many detergents.

• Bradford Assay Kits — rapid dye-binding readout; convenient when speed matters more than detergent tolerance.

• Precast Gels (Bis-Tris / Tris-Glycine) — multiple percentages and gradient formats to match your target size.

• PVDF/Nitrocellulose Membranes — pore-size options for small or large proteins; low background formulations available.

• ECL Chemiluminescent Substrates — select standard, sensitive, or ultra-sensitive depending on target abundance.

• Ni-NTA / Co-NTA Resins & Magnetic Beads — scalable from spin to gravity to FPLC; choose Co for higher specificity.

• Protein A/G Beads — reliable IgG capture for IP/Co-IP; available in magnetic and agarose formats.

• Trypsin & Lys-C Digestion Kits — sequencing-grade enzymes with clear protocols and cleanup options.

• Desalting Spin Columns/Plates — fast buffer exchange prior to MS or labeling steps.

• Reference & Custom Peptides — standards for method QC and fully customized sequences with MS/HPLC documentation.

FAQs

Q1. BCA vs. Bradford—how should I choose?
Pick BCA for broader linear range and better compatibility with many detergents; pick Bradford when you need fast results and your buffer lacks interfering detergents.

Q2. Ni-NTA or Co-NTA for His-tagged proteins?
Start with Ni-NTA for capacity and cost; switch to Co-NTA when you need higher purity or you observe nonspecific binding.

Q3. Which crosslinker chemistry fits my experiment?
Use NHS-ester reagents for amines (e.g., lysine); maleimide for free thiols (cysteine). Zero-length options preserve native distance but require reactive pairs.

Q4. How do I prepare samples for LC-MS?
Reduce/alkylate to control disulfides, digest with sequencing-grade trypsin or Lys-C, then desalt on spin columns or plates before loading with LC-MS-grade solvents.

Q5. What peptide purity should I order?
Method development and screening can start with desalted material; quantitative assays or standards typically require HPLC-purified peptides with MS/HPLC documents.

Q6. How should peptides be stored?
Store lyophilized peptides at −20 °C (or colder), protected from moisture and light; aliquot solutions to minimize freeze–thaw cycles and follow the COA for stability.

Talk to Iright

If you want help finalizing choices or need a formal quote, contact Iright. We can confirm current availability, recommend compatible kits for your workflow, and supply the exact Thermo Fisher catalog numbers you require. Tell us your sample type, target size, and detection method—we’ll match products and provide lead times.