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Aminated covalent organic polymer (ACOP) was synthesized through a catalyst-free Schiff base reaction involving terephthalaldehyde and melamine, and the prepared ACOP was used for the adsorption of anionic dyes. The prepared ACOP possessed a high specific surface area (582.07 m2/g) with an average pore size of 88.71 Å. Its point of zero charge was determined as pH 8.26. Anionic dye molecules, methyl orange (MO) and orange G (OG), were used to evaluate the dye adsorption efficiency of the prepared ACOP, and it was found that they were adsorbed rapidly on ACOP within 1 min. The maximum adsorption capacities (qm) of the prepared ACOP for MO and OG were 351.9 and 227.9 mg/g, respectively. Furthermore, the results of dye adsorption as a function of the initial pH and presence/absence of cationic dye (methylene blue; MB) revealed that dye adsorption on ACOP proceeded through charge–charge and π–π interactions. The presence of MB along with MO and OG enhanced the dye adsorption capacity because of the synergistic effect of the positively charged quaternized nitrogen atoms in the prepared ACOP. The dye adsorption mechanism was further investigated using Fourier transform infrared (FT-IR) analysis and X-ray photoelectron spectrometry (XPS). The ACOP adsorbent prepared herein using a facile catalyst-free reaction offers rapid adsorption with a high adsorption efficiency over a wide pH range and in the presence of cationic dye. For these reasons, it can be used for environmental remediation, especially in aqueous systems.

Trastuzumab emtansine (T-DM1, brand name: Kadcyla®) is the first FDA-approved antibody-drug conjugate (ADC) for metastatic human epidermal growth factor receptor 2 positive (HER2+) breast cancer. It consists of three components: trastuzumab, an anti-HER2 monoclonal antibody, maytansinoid (DM1) as a cytotoxic drug, and maleimidomethyl cyclohexane-1-carboxylate (MCC) as a linker. In particular, the MCC linker is known as a non-cleavable linker and has a feature of being conjugated to DM1 by a covalent thioether bond. In this study, we developed an immuno-affinity capture liquid chromatography-mass spectrometric (LC-MS/MS) assay for quantifying the antibody-conjugated drug (acDrug) component of T-DM1. To quantify acDrug, desulfurated DM1 was prepared using a chemical desulfuration pretreatment and quantified as an acDrug. A quadratic regression (weighted 1/concentration), with equation y = ax2 + bx + c, was used to fit the calibration curves over the concentration range of 17.09~1709.44 ng/mL for the acDrug of T-DM1. The quantification run met the in-house acceptance criteria of ±25% accuracy and precision values for the quality control (QC) samples. In conclusion, an immuno-affinity capture LC-MS/MS assay was successfully developed to quantify acDrug of T-DM1 and applied to evaluate in vitro plasma linker stability and preclinical pharmacokinetic (PK) study in rats. This assay could be helpful when applied to other ADCs with the same linker-cytotoxic drug platform.