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Lipopolysaccharide (LPS), as a stubborn contamination, should be monitored and kept in an acceptable level during the pharmaceutical production process. Recombinant hepatitis B surface antigen (r-HBsAg) is one of the recombinant biological products, which is probable to suffer from extrinsic endotoxin due to its long and complex production process. This research aims to assess the potential interaction between LPS and r-HBsAg by recruiting immunoaffinity chromatography (IAC) as a novel tool to quantify the interaction. Molecular modeling was performed on the HBsAg molecule to theoretically predict its potential binding and interaction sites. Then dynamic light scattering (DLS) analysis was implemented on HBsAg, LPS, and mixtures of them to reveal the interaction. The virus-like particle (VLP) structure of HBsAg and the ribbon-like structure of LPS were visualized by transmission electron microscopy (TEM). Finally, the interaction was quantified by applying various LPS/HBsAg ratios ranging from 1.67 to 120 EU/dose in the IAC. Consequently, the LPS/HBsAg ratios in the eluate were measured from 1.67 to a maximum of 92.5 EU/dose. The results indicated that 77 to 100% of total LPS interacted with HBsAg by an inverse relationship to the incubated LPS concentration. The findings implied that the introduced procedure is remarkably practical in the quantification of LPS interaction with a target recombinant protein. [ABSTRACT FROM AUTHOR]

Various industries ranging from water purification to pharmaceutical production have experienced multi separation steps that impose more process time and contamination possibility by batch operation. We propose a developed microfluidic particle sorter (miniaturized hydrocyclone) that adopts centrifugal force as it has ability to decline the number of separation steps and the risk of extrinsic contamination in continuous process. While biological industries have not relied on mini hydrocyclones considerably because of low efficiency and microfabrication difficulties, current work has been planned to conquer these obstacles. In this research, biomass separation from fermentation broth by 3 mm hydrocyclones was investigated. The effect of apex size, feed flow rate, hydrocyclone geometry were analyzed numerically in four mini-hydrocyclones. The most efficient mini-hydrocyclone was chosen to be made by elegant additive manufacturing technology and studied experimentally. The separation efficiency was achieved up to 90% while the concentration ratio of heavy stream (apex) to dilute stream (vortex finder) was reached more than twofold. The mini hydrocyclone performance in view of energy target was studied by Euler-Reynolds-Efficiency plots. The 4 μm cut size was achieved that is promising high throughput separation for biological particles. [ABSTRACT FROM AUTHOR]

Delay in inpatient discharge processes reduces patient satisfaction and increases hospital congestion and length of stay. Further, flow congestion manifests as patient boarding, where new patients awaiting admission are blocked by bed unavailability. Finally, length of stay is extended if the discharge delay incurs an extra overnight stay. These factors are often in conflict, thus, good hospital performance can only be achieved through careful balancing. We formulate the discharge planning problem as a two-stage stochastic program with uncertain discharge processing and bed request times. The model minimizes a combination of discharge lateness, patient boarding, and deviation from preferred discharge times. Patient boarding is integrated by aligning bed requests with bed releases. The model is solved for different instances generated using data from a large hospital in Texas. Stochastic decomposition is compared with the extensive form and the L-shaped algorithm. A shortest expected processing time heuristic is also investigated. Computational experiments indicate that stochastic decomposition outperforms the L-shaped algorithm and the heuristic, with a significantly shorter computational time and small deviation from optimal. The L-shaped method solves only small problems within the allotted time budget. Simulation experiments demonstrate that our model improves discharge lateness and patient boarding compared to current practice. [ABSTRACT FROM AUTHOR]

The interaction of lipopolysaccharide with a recombinant protein is a serious bottleneck, particularly in the purification step of bioprocessing. Recombinant hepatitis B surface antigen (rHBsAg), the active ingredient of the hepatitis B vaccine, is probably contaminated by extrinsic LPS like other biopharmaceuticals. This research intends to eliminate LPS from its mixture with rHBsAg efficiently. Immobilized polymyxin B on magnetic nanoparticles (PMB-MNPs) was synthesized and implemented as an enhanced LPS affinity adsorbent (LAA). The 20-80 EU/dose binary samples with and without surfactant were applied to PMB-MNPs. Formerly, dynamic light scattering (DLS) and transmission electron microscopy (TEM) were examined on the samples to qualitatively show the dissociation effect of the surfactant. Considering the high potential interaction of LPS with HBsAg, the dissociation effects of 0.5 and 1.5% Tween 20 on the binary samples were assessed using immunoaffinity chromatography (IAC) as a quantification tool. The dissociation effect of Tween 20 substantially diminished the interaction, leading to a proportional increase of free LPS up to 66%. The synergetic effect of Tween 20 and privileged LAA was highly effective in eliminating more than 80% of LPS with a remarkable LPS clearance factor of 5.8 and a substantial protein recovery rate of 97%.

Background: Injectable products, particularly human vaccines, must be free from fever-inducing agents and thoroughly tested for pyrogens as part of a quality control. Consequently, manufacturing facilities are required to conduct appropriate pyrogen tests per pharmacopeial standards. This study aimed to evaluate the reliability of the MAT in quantifying pyrogenic content in the recombinant hepatitis B vaccine., Methods: We assessed pyrogen activity in the API, formulated vaccine, and aluminum hydroxide by comparing the LAL, RPT, and MAT, measuring activity in RPU as per the European Pharmacopeia. Monocytes from healthy donors were isolated and identified via flow cytometry to measure the CD14+ marker frequency., Results: The study found that the pyrogenic concentration of LTA in the MAT was 50,000 ng/mL (5.19 EEU/mL). In contrast, the same concentration in the RPT was deemed non-pyrogenic based on rectal temperature assessments. The MAT showed sensitivity to the API and adjuvant, with a detection limit of 2.5 EU/mL for IL-6, outperforming the RPT, which had a detection limit of 5 EU/mL., Conclusion: A strong IL-6 response to both LPS and LTA stimulation was observed, indicating that IL-6 could serve as a valuable marker for pyrogen testing. The MAT appears to be an effective alternative to the RPT for assessing pyrogenicity, demonstrating commendable consistency and accuracy across various testing systems allowed by the Ph. Eur. General MAT Chapter, especially given the RPT's limitations in controlling pyrogenicity in injectable products.