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Abstract We report the integration of 3D printing, electrobiofabrication, and protein engineering to create a device that enables near real‐time analysis of monoclonal antibody (mAb) titer and quality. 3D printing was used to create the macroscale architecture that can control fluidic contact of a sample with multiple electrodes for replicate measurements. An analysis “chip” was configured as a “snap‐in” module for connecting to a 3D printed housing containing fluidic and electronic communication systems. Electrobiofabrication was used to functionalize each electrode by the assembly of a hydrogel interface containing biomolecular recognition and capture proteins. Specifically, an electrochemical thiol oxidation is used to assemble a thiolated polyethylene glycol hydrogel, that in turn is covalently coupled to either a cysteine‐tagged protein G that binds the antibody's Fc region or a lectin that binds the glycans of target mAb analytes. We first show the design, assembly, and testing of the hardware device. Then, we show the transition of a step‐by‐step sensing methodology (e.g., mix, incubate, wash, mix, incubate, wash, measure) into the current method where functionalization, antibody capture, and assessment are performed in situ and in parallel channels. Both titer and glycan analyses were found to be linear with antibody concentration (to 0.2 mg/L). We further found the interfaces could be reused with remarkably similar results. Because the interface assembly and use are simple, rapid, and robust, we suggest this assessment methodology will be widely applicable, including for other biomolecular process development and manufacturing environments.
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Simple, rapidly electroassembled thiolated PEG‐based sensor interfaces enable rapid interrogation of antibody titer and glycosylation
Abstract Process conditions established during the development and manufacture of recombinant protein therapeutics dramatically impacts their quality and clinical efficacy. Technologies that enable rapid assessment of product quality are critically important. Here, we describe the development of sensor interfaces that directly connect to electronics and enable near real‐time assessment of antibody titer and N‐linked galactosylation. We make use of a spatially resolved electroassembled thiolated polyethylene glycol hydrogel that enables electroactivated disulfide linkages. For titer assessment, we constructed a cysteinylated protein G that can be linked to the thiolated hydrogel allowing for robust capture and assessment of antibody concentration. For detecting galactosylation, the hydrogel is linked with thiolated sugars and their corresponding lectins, which enables antibody capture based on glycan pattern. Importantly, we demonstrate linear assessment of total antibody concentration over an industrially relevant range and the selective capture and quantification of antibodies with terminal β‐galactose glycans. We also show that the interfaces can be reused after surface regeneration using a low pH buffer. Our functionalized interfaces offer advantages in their simplicity, rapid assembly, connectivity to electronics, and reusability. As they assemble directly onto electrodes that also serve as I/O registers, we envision incorporation into diagnostic platforms including those in manufacturing settings.
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- PAR ID:
- 10226414
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biotechnology and Bioengineering
- Volume:
- 118
- Issue:
- 7
- ISSN:
- 0006-3592
- Format(s):
- Medium: X Size: p. 2744-2758
- Size(s):
- p. 2744-2758
- Sponsoring Org:
- National Science Foundation
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