This is a personalized conjugation kit (PerKit™) to work with any protein with a MW over 20 KDa and for protein labeling of a small molecule containing carboxylic acid (-COOH) functional groups. Using the kit components, the customer converts the carboxylic acid to an activated N-hydroxysuccinimide (NHS) ester, followed by reaction with the surface amino groups of the protein to form a stable amide bond. The final product is desalted to remove any unreacted small molecule acid.
This kit provides materials to label 15-50 nmole of one protein sample (≥20 KDa)
Requirement for Small Molecule
- Preferably > 90% pure
- Absence of primary or secondary amine (-NH2) groups
- Preferably contains only one non-hindered aliphatic carboxylic acid (-COOH)
- For molecule containing aromatic carboxylic acid, hindered aliphatic carboxylic acid, or hydroxyl (-OH) groups, please consult CellMosaic first before placing the order.
Key Features of this PerKit™
- Offers a simple and easy way to label protein with any small molecule containing carboxylic acid
- Fast and easy preparation: 4 h preparation and <30 minutes hands-on time
- All reagents and supplies included for preparation and purification
- Over 90% pure conjugated products by SEC
- Options to choose tailored services at CellMosaic after conjugation
After conjugation: you can choose to send your sample to CellMosaic for HPLC analysis and calculation of the loading.
Schematic diagram of the workflow for preparing protein-small molecule conjugates starting with 50 nmole of protein (volume of reagents varies if the amount of protein is < 50 nmole)
Typical Kit Performance Data
SM acid information: 6-carboxyfluorescein (20 µmol)
Protein information: Bovine Serum Albumin (BSA) (50 nmol)
Kit Lot number: 5506.S51207
Figure 1: Size-exclusion HPLC analysis of the purified fluorescein labeled BSA from Step D6 using various amounts of Fluorescein NHS ester.
Figure 2: UV/Vis spectrum of the purified fluorescein labeled BSA from Step D6 using various amounts of Fluorescein NHS ester.
Table 1: Summary results of the purity and the average DOL of the fluorescein labeled BSA from Step D6 (Note: Fluorescein is a very hydrophobic compound. A lower DOL was obtained.)
|Sample||NHS ester solution from Step B7 (µl)||SEC HPLC Rt (min) 220 nm||ΔRt||% of small molecule after purification||Calc. DOL based on UV/Vis|