We have the technology to synthesize PEG molecules with a specific number of ethylene oxide units, providing a highly pure product that has a monodisperse weight and length. The purity of our products comes from purification techniques that we have accumulated from the development of various PEGs.
In addition, we can supply specific length PEGs at various molecular weights and with select architectures (linear or branched type) and functional groups such as maleimide, Boc, azide, as well as amino group and carboxyl group by applying our synthetic techniques developed for standard activated PEGs.
Furthermore, we have reliable test methods to determine the exact purity of the monodisperse PEGs with their terminal activity and the number of EG units.
The monodisperse PEG linkers dramatically improve solubility and yield in the process of ADC preparation. In addition the use of PEG linkers for ADCs can prevent aggregation derived from payloads hydrophobic interaction and improve stability in storage.
Solubility and yield in the process of ADC preparation
| SMCC linker | PEG linker | |
|---|---|---|
| DAR | Solubility / Yield* | |
| 3~5 | Soluble / 47% | Soluble / 95% |
| 11 | Precipitation / 7% | Soluble / 73% |
* Yield of ADC was calculated from total mAb concentration (by BCA assay)
Antibody: Trastuzumab, Drug: DM-1, Linker: SMCC or PEG (n = 24) linker
Figure. Aggregation behavior of ADCs by Size-Exclusion Chromatography (SEC) in Storage.
a) SEC-UPLC charts of the ADCs prepared with SMCC linker. b) Aggregate (%) of the ADCs.
Stock condition;
Buffer: sodium succinate (10 mM) + sucrose (6%w/v) + polysorbate 20 (0.05%w/v), pH5.0,
Concentration: 8 mg/mL, Incubation temp: 40 ºC, Incubation time: 14 days.