Optimal Design in Roller Pump System Applications for Linear Infusion

Solid-Solid Interfacial Contact of Tubing Walls Drives Therapeutic Protein Aggregation During Peristaltic Pumping

Peristaltic pumping during bioprocessing can cause therapeutic protein loss and aggregation during use. Due to the complexity of this apparatus, root-cause mechanisms behind protein loss have been long sought. We have developed new methodologies isolating various peristaltic pump mechanisms to determine their effect on monomer loss. Closed-loops of peristaltic tubing were used to investigate the effects of peristaltic pump parameters on temperature and monomer loss, whilst two mechanism isolation methodologies are used to isolate occlusion and lateral expansion-relaxation of peristaltic tubing. Heat generated during peristaltic pumping can cause heat-induced monomer loss and the extent of heat gain is dependent on pump speed and tubing type. Peristaltic pump speed was inversely related to the rate of monomer loss whereby reducing speed 2.0-fold increased loss rates by 2.0- to 5.0-fold. Occlusion is a parameter that describes the amount of tubing compression during pumping. Varying this to start the contacting of inner tubing walls is a threshold that caused an immediate 20-30% additional monomer loss and turbidity increase. During occlusion, expansion-relaxation of solid-liquid interfaces and solid-solid interface contact of tubing walls can occur simultaneously. Using two mechanisms isolation methods, the latter mechanism was found to be most destructive and a function of solid-solid contact area, where increasing the contact area 2.0-fold increased monomer loss by 1.6-fold. We establish that a form of solid-solid contact mechanism whereby the contact solid interfaces disrupt adsorbed protein films is the root-cause behind monomer loss and protein aggregation during peristaltic pumping.

Design, Simulation and Multi-Objective Optimization of a Micro-Scale Gearbox for a Novel Rotary Peristaltic Pump

Peristaltic pumps are widely used in biomedical applications to ensure the safe flow of sterile or medical fluids. They are commonly employed for drug injections, IV fluids, and blood separation (apheresis). These pumps operate through a progressive contraction or expansion along a flexible tube, enabling fluid flow. They are also utilized in industrial applications for sanitary fluid transport, corrosive fluid handling, and novel pharmacological delivery systems. This research provides valuable insights into the selection and optimal design of the powertrain stages for peristaltic pumps implemented in drug delivery systems. The focus of this paper lies in the simulation and optimization of the performance of a power transmission gearbox by examining the energy consumption, sound levels, reliability, and volume as output metrics. The components of the powertrain consist of a helical gear pair for the first stage, a bevel gear pair for the second one, and finally a planetary transmission. Through extensive simulations, the model exhibits promising results, achieving an efficiency of up to 90%. Furthermore, alternative configurations were investigated to optimize the overall performance of the powertrain. This process has been simulated by employing the KISSsoft/KISSsys software package. The findings of this investigation contribute to advancements in the field of biomedical engineering and hold significant potential for improving the efficiency, reliability, and performance of drug delivery mechanisms.

Reaching the breaking point: Effect of tubing characteristics on protein particle formation during peristaltic pumping

Peristaltic pumping has been identified as a cause for protein particle formation during manufacturing of biopharmaceuticals. To give advice on tubing selection, we evaluated the physicochemical parameters and the propensity for tubing and protein particle formation using a monoclonal antibody (mAb) for five different tubings. After pumping, particle levels originating from tubing and protein differed substantially between the tubing types. An overall low shedding of tubing particles by wear was linked to low surface roughness and high abrasion resistance. The formation of mAb particles upon pumping was dependent on the tubing hardness and surface chemistry. Defined stretching of tubing filled with mAb solution revealed that aggregation increased with higher strain beyond the breaking point of the protein film adsorbed to the tubing wall. This is in line with the decrease in protein particle concentration with increasing tubing hardness. Furthermore, material composition influenced particle formation propensity. Faster adsorption to materials with higher hydrophobicity is suspected to lead to a higher protein film renewal rate resulting in higher protein particle counts. Overall, silicone tubing with high hardness led to least protein particles during peristaltic pumping. Results from this study emphasize the need of proper tubing selection to minimize protein particle generation upon pumping.