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Nanofluidic device for continuous multiparameter quality assurance of biologics


Process analytical technology (PAT) is critical for the manufacture of high-quality biologics as it enables continuous, real-time and on-line/at-line monitoring during biomanufacturing processes. The conventional analytical tools currently used have many restrictions to realizing the PAT of current and future biomanufacturing. Here we describe a nanofluidic device for the continuous monitoring of biologics’ purity and bioactivity with high sensitivity, resolution and speed. Periodic and angled nanofilter arrays served as the molecular sieve structures to conduct a continuous size-based analysis of biologics. A multiparameter quality monitoring of three separate commercial biologic samples within 50 minutes has been demonstrated, with 20 µl of sample consumption, inclusive of dead volume in the reservoirs. Additionally, a proof-of-concept prototype system, which integrates an on-line sample-preparation system and the nanofluidic device, was demonstrated for at-line monitoring. Thus, the system is ideal for on-site monitoring, and the real-time quality assurance of biologics throughout the biomanufacturing processes.

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Figure 1: Schematics of the slanted nanofilter array fabricated for both purity and bioactivity monitoring.
Figure 2: Quantification of the limit of detection for three biologic drugs in the slanted nanofilter array system.
Figure 3: Size-based separation of biologic drugs and protein markers in the slanted nanofilter array system.
Figure 4: Demonstration of homogeneous affinity binding assay using peptides and receptors for different drugs.
Figure 5: Purity and bioactivity assessments of the forced degraded drugs hGH, IFN and G-CSF.
Figure 6: Proof-of-concept prototype for the at-line purity assessment of supernatants of a CHO-K1 cell culture (3.4 million cells per millilitre of batch culture) that contains antibody products (IgG1) using an on-line sample preparation system and the nanofluidic device (ds of 20 nm and dd of 100 nm).


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We thank P. Mao for providing advice on the nanofilter fabrication, the MIT Microsystems Technology Laboratories for support in the fabrication, P. W. Barone for discussion and assistance with the sample handling and J.-F. P. Hamel for his support in the cell culture and analysis. This work was mainly supported by the Defense Advanced Research Projects Agency and SPAWAR Systems Center Pacific (N66001-13-C-4025) to S.H.K., D.C., W.O., T.K., P.K. and J.H. a Siebel fellowship to W.O. and a Samsung Scholarship to T.K.

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S.H.K. and J.H. conceived the project and S.H.K. designed and fabricated the device. S.H.K. conceived and performed the experiments for purity and activity monitoring with both non-degraded and degraded drugs using the at-line monitoring system and analysed the data. D.C. screened and provided peptide sequences for hGH and IFN, W.O. provided information on how to prepare the degraded drugs, T.K. cultured CHO-K1 cells in batch mode and provided IgG1. S.H.K. and J.H. wrote the manuscript, and J.H. and P.K. supervised the project.

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Correspondence to Jongyoon Han.

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Competing interests

J.H. and S.H.K. have filed a patent application for the nanofilter device. P.K. and D.C. plan on filing patent applications for the peptide ligands.

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Ko, S., Chandra, D., Ouyang, W. et al. Nanofluidic device for continuous multiparameter quality assurance of biologics. Nature Nanotech 12, 804–812 (2017).

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