Ordering information
Name	Cat. No.	Vol.	Scheme
G-N3	PMG012-2	2 ml

1. Overview

Click Chemistry describes rapid, selective "click" reactions between paired functional groups in mild aqueous solutions. This concept has evolved into a convenient, versatile, and reliable two-step coupling procedure for molecules A and B, widely adopted in biosciences, drug discovery, and materials science.

PuriMag™ G-N₃, Azide-Functionalized Magnetic Nanoparticles are uniform, polymer-coated superparamagnetic nanoparticles. Their hydrophilic surface ensures excellent dispersibility, low non-specific adsorption, and easy handling in diverse buffers. The beads feature a high-density surface coating of azide active groups, enabling covalent capture of functionalized proteins via:

• Cu(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAC)

• Cu(I)-free Azide-DBCO Click Chemistry

Workflow Requirements:

• Target proteins must be metabolically, enzymatically, or chemically tagged with:

  • Alkyne groups (for CuAAC)

  • DBCO groups (for Cu(I)-free reactions)

• Post-coupling, rigorous washing eliminates non-specifically bound proteins.

• Unique surface chemistry ensures low background binding without surfactants.

Features & Advantages:
• High binding capacity
• Rapid, efficient coupling
• Hydrophilic long-arm spacers minimize steric hindrance/non-specific binding
• Charge-neutral surface post-coupling
• Stable covalent bonds with minimal ligand leakage
• Low non-specific binding
• Capacity: 1–20 mg protein or 0.1–2 mg peptide per gram beads

Caution: Azide beads are unstable in organic solvents and high urea concentrations.

Schematic Diagram of Bead Coupling Mechanism:

2. product description

Product Specifications
Description	Polymer coated Fe3O4 nanoparticles
Particle Size	200 nm
Number of Beads	~1.7×1010 beads/mg
Matrix	Proprietary polymer
Functional group	Azide group
Group density	~300 µmole / g of Beads
Magnetization	60~70 EMU/g
Formulation	10mg/mL in DI water
Storage	1 year at 2~8 ℃. Do not freeze.

3. Instructions for Use

A. Required Materials
    tert-Butyl alcohol (t-BuOH): 12 mL
    Dimethylsulfoxide (DMSO): 3 mL
    Tris[(1-benzyl-1H-1,2,3-triazol-4-yl)methyl]amine (TBTA), M.W. 530.63: 2.7 mg
    Copper(II) sulfate (CuSO₄), M.W. 159.61: 16 mg
    (＋)-Sodium L-ascorbate, M.W. 198.11: 20 mg
    Methanol (MeOH): 4 mL

B. Coupling Method
    For screening, optimize ligand immobilization density on PuriMag™ beads by testing four concentrations: 0 μM, 5 μM, 25 μM, and 125 μM.

B-1. Solution Preparation

    1.Prepare 15 mL t-BuOH/DMSO (4:1) by mixing 12 mL t-BuOH + 3 mL DMSO.

    2.Dissolve ligand in t-BuOH/DMSO to prepare 200 μL of 500 μM ligand solution.

    3.Prepare 1 mL 5 mM TBTA (2.7 mg in t-BuOH/DMSO). Dilute 10 μL to 200 μL with t-BuOH/DMSO for 250 μM TBTA.

    4.Prepare 1 mL 100 mM CuSO₄ (16 mg in H₂O). Dilute 10 μL to 200 μL with H₂O for 5 mM CuSO₄.

    5.Prepare 1 mL 100 mM sodium L-ascorbate (20 mg in H₂O). Dilute 10 μL to 200 μL with H₂O for 5 mM solution.

    6.Prepare 8 mL t-BuOH/DMSO/H₂O (1:1) by mixing 4 mL t-BuOH/DMSO + 4 mL H₂O.

B-2. Ligand Immobilization

    1.Aliquot 2.5 mg azide beads into four tubes. Separate magnetically (RT), discard supernatant.

    2.Add 500 μL t-BuOH/DMSO, disperse beads. Separate (RT), discard supernatant.

    3.Repeat Step 2 twice (total 3 washes for solvent exchange).

    4.Add reaction solutions in sequence (see table below). After adding 250 μM TBTA, disperse ultrasonically. Then add remaining solutions.

Concentration (um)	0	5	25	125
Azide beads (mg)	2.5	2.5	2.5	2.5
t-BuOH/DMSO (ul)	250	240	200	0
500uM ligands (ul)	0	5	25	125
250uM TBTA (ul)	0	5	25	125
Ultrapure water (ul)	250	240	200	0
5mM CuSO4 (ul)	0	5	25	125
5mM (＋)-Sodium L-ascorbate (ul)	0	5	25	125
Total  (ul)	500	500	500	500

    5.React with tube mixer 16–20 h at RT.

    6.Separate magnetically (RT), discard supernatant.

    7.Add 500 μL t-BuOH/DMSO/H₂O, disperse ultrasonically.

    8.Separate (RT), discard supernatant.

    9.Repeat Steps 7–8 twice (total 3 washes).

    10.Add 500 μL 50% MeOH, disperse ultrasonically.

    11.Separate (RT), discard supernatant.

    12.Repeat Steps 10–11 twice (total 3 washes).

    13.Resuspend in 100 μL 50% MeOH. Store at 4°C.

        (Ligand-immobilized bead concentration: 0.5 mg/20 μL)

        (For research use only!)