Merck Millipore was the brand used for Merck's global life science business until 2015 when the company re-branded. It was originally formed when Merck acquired the Millipore Corporation in 2010. Merck is a supplier to the life science industry. The Millipore Corporation was founded in 1954, and listed among the S&P 500 since the early 1990s, as an international biosciences company, known widely for its micrometer pore-size filters and tests. In 2015, Merck acquired Sigma-Aldrich and merged it with Merck Millipore. In the United States and Canada, the life science business is now known as MilliporeSigma.
Recently, a mixture of hemoglobin (Hb) and bovine serum albumin (BSA) was separated into two highly purified fractions with high recovery via internally staged ultrafiltration (ISUF) having a stack of three identical flat 100 kDa ultrafiltration (UF) membranes in a stirred cell. Selectivities as high as 1000-4000+, and high recoveries of individual species were achieved. Successful separation and purification of IgG from a BSA-IgG mixture was also achieved in a stirred cell using a modified ISUF technique with two 100 kDa membranes on a 70 kDa membrane; here BSA was a model for host cell proteins (HCPs) in post-protein A eluate. We explored here separation and purification of the Hb-BSA system in a developmental cassette of 88 cm(2) membrane surface area, having a stack of three 100 kDa membranes on each side of the channel. The channel gap was smaller than that in regular cassettes resulting in higher flow pressure drops. The Hb-BSA separation was studied over a diavolume (DV) range of similar to 0-6. The Hb-BSA selectivity was as high as 1600 and remained above 300 till 6 DV. Lower feed pressure and a particular permeate collection mode leading to reduced transmembrane pressure drop were crucial for higher performance. Species recoveries were lower for the DV range used especially compared to those in a stirred cell. Successful separation and purification of BSA-IgG system was also demonstrated with similar limitations. Increased flow pressure drop due to flow channel height reduction in existing cassette frames and lower flow rates leading to higher concentration polarization suggest modification of the cassette frame for high performance ISUF for difficult-to-separate protein mixtures in biopharmaceutical separation processes.
Ensuring strong adhesion between porous polymeric membranes and supporting substrates is critical for the reliability and functionality of membrane devices. However, due to the innate low surface energy of polymers, achieving strong chemical bonding between such materials remains challenging. In addition, the small-pore size of membranes often limits effective pore intrusion (necessary for achieving effective mechanical interlocking) by polymer adhesives during high-throughput manufacturing. Plasma treatment is commonly used to modify the surface energy of polymers to improve adhesion and mechanical properties of composite systems. However, it remains unexplored whether the method is effective in improving the adhesion of surfaces containing nanoscale pores as found in membranes. Herein, we demonstrate that adhesion between poly(ethersulfone) (PES) membranes with 20 and 200 nm pore sizes and polypropylene (PP) substrates is enhanced by low-pressure plasma treatment (power: 30 W, duration: 60 s, gas flow rate: 30 cm3/min) of the two surfaces. Thermomechanical bonding between the treated surfaces is performed, and the adhesion behavior is quantified by a T-peel test and imaging analysis. For the 200 nm PES membranes and PP substrate, the adhesion after plasma treatment (152-405 N/m), measured by the interfacial fracture toughness, exhibits an improvement by 0.12 to 2 times in comparison to untreated control samples (114-156 N/m). For the 20 nm PES membranes and PP substrate, the adhesion after plasma treatment (14-242 N/m) exhibits an improvement by 0.13 to 20 times in comparison to that of untreated control samples (12-96 N/m). Among the different types of plasma treatment tested, the oxygen-containing plasmas produce the largest enhancement in adhesion. When benchmarked against the adhesion of densified, nonporous PES film and PP substrates after plasma treatments (0-20 N/m), the adhesion is improved by 13 to 37 times for the 200 nm PES/PP specimens and by 1.5 to 17 times for the 20 nm PES/PP specimens, showcasing the importance of mechanical interlocking due to membrane pore structure for adhesion. This study shows that there is a synergistic effect of chemical bonding and mechanical interlocking on the interfacial fracture toughness between porous membranes and thermoplastic substrates, which can be useful in guiding the membrane bonding process in a variety of applications.
Abstract Automated multiplex bead-based immunoassays were performed using an AAW™ Automated Assay Workstation for high-throughput profiling of immune factors and cancer autoantibodies. Human serum cytokine analysis was conducted with MILLIPLEX Human Cytokine Panel A and Panel B kits (48-plex, overnight protocol), and across cytokines spanning a broad dynamic range, automated-to-manual correlation coefficients (R2) were greater than 0.95 with regression slopes between 0.80 and 1.20. Cancer autoantibody profiling used a 15-plex antigen-coated bead multiplex panel on sera from various cancer types and healthy donors (n=96 total samples). The AAW™ workstation automates all critical liquid handling, standard curve preparation, sample transfer, reagent dispensing (matrix solution, Assay Buffer, Standards, QCs, samples, and Beads), and plate setup with robotic lidding. Assay plates were washed off-deck on an automatic plate washer and analyzed with a Luminex instrument. The automated protocol enabled processing of 2-3 plates daily, with streamlined setup which significantly reduce hands-on time. Minimizing manual interventions reduced opportunities for human errors, resulting in greater reliability and efficiency for high-throughput applications. The AAW™ performance confirms robust, reproducible, and scalable multiplex analysis for cancer and immunology research. Citation Format: Wen-Rong Lie, Brooke Gilliam, Laura Marquardt, Mark Pawlicki, Ernest Mueller, Xiuyuan Zhang, Nathanael Ellis, Todd Hendrich, Linda Meeh, Scott Keefer, Qiang Xiao, . Automated multiplex profiling of human cytokines and autoantibodies using an Automated Assay Workstation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7669.
