Tangential Flow Filtration Of Liposomal Nanoparticles Results In 10X Concentration Within 20 Minutes Under Controlled Pressure Conditions

Tangential flow filtration (TFF) is a widely used method to perform concentration and diafiltration on biological formulations, including liposomal nanoparticles, LNPs and polymeric nanocarriers.

A novel single-pass, TFF process was carried out using the DIANT® PILOT sp2TFF system to concentrate and buffer exchange liposomal nanoparticles. The buffer exchange allows for the reduction of solvent (e.g. ethanol). DIANT has developed this process to accommodate TFF Feed flow rates from 50 mL/min to 3,000 mL/min, and can be scaled linearly to higher flow rates using the same DIANT equipment.

The objective of this study was to achieve a 10-fold increase in concentration. The process parameters included Feed, Retentate and Permeate flow rates, with the system monitoring throughout the operation for pressure, flow stability, and concentration metrics. The data indicated that a constant-state concentration phase was reached within approximately 15 to 20 minutes of initiating the run, with pressure and flow conditions remaining within expected ranges. These findings suggest that the DIANT® PILOT sp2TFF system can support nanoparticle concentration workflows under defined conditions and recipes.

Materials and Methods:

  • System Used: DIANT Pharma PILOT sp2TFF
  • Filtration Mode: Single-pass tangential flow filtration
  • Objective: Concentrate liposome nanoparticles by a factor of 10
  • Feed Flow Rate: 100 mL/min
  • Retentate Flow Rate: 10 mL/min
  • Monitoring Parameters:
    – Transmembrane pressure (PSI)
    – Flow rate (mL/min)
    – Concentration (NIR CU/PPM)

The process was performed under ambient laboratory conditions. The feed material consisted of a liposomal nanoparticle dispersion prepared using the DIANT® PILOT system. The system was operated continuously, and data was logged in real time for both feed, retentate and permeate streams.

Concentration Behavior:

During the initial phase of the run, a gradual increase in concentration was observed, with constant-state conditions being reached within approximately 15 to 20 minutes. This was determined by monitoring changes in concentration units (CU) and parts per million (PPM) over time.

Flow Stability:

The two retentate streams, designated as TFF1 and TFF2, maintained consistent flow throughout the process. No significant fluctuations in flow rate were recorded, and no blockages or interruptions were noted.

Pressure Profile:

Throughout the run, both filtration modules maintained a maximum operating pressure of approximately 6 PSI. This value remained stable throughout the duration of the operation and fell within the expected operating range for the system configuration used.

Graphical Data:

A time-based graph generated during the run demonstrated consistent flow profiles and a clear concentration increase up to the 10X target. The graph also reflected stable pressure readings, with no observable spikes or anomalies.

The DIANT® PILOT sp2TFF system, designed for single-pass filtration, was able to process the liposomal nanoparticles under controlled flow and pressure parameters. The use of a 10:1 feed-to-retentate ratio contributed to the progressive concentration over time, reaching the target level without deviation from set flow conditions.

The approximately 6 PSI maximum pressure observed aligns with safe operating guidelines for TFF of lipid-based nanoparticles, which can be sensitive to shear and pressure-induced structural changes. Maintaining a low-pressure environment is particularly important for preserving nanoparticle integrity, especially for shear sensitive structures such as lipid nanoparticles.

The ability to reach a constant concentration state within 20 minutes suggests that the system can achieve predictable concentration kinetics when operated under these defined conditions.

The single-pass tangential flow filtration process using the DIANT® PILOT sp2TFF system achieved a tenfold concentration of liposome nanoparticles in approximately 20 minutes. Throughout the run, both pressure and flow conditions remained stable and within predefined operating parameters. This outcome reflects the performance of the system under the specific conditions and formulation used in this procedure.

About The Technology:

The DIANT® PILOT sp2TFF system is a modular tangential flow filtration platform developed by DIANT Pharma Inc., specifically designed for continuous and single-pass concentration and diafiltration processes. Featuring integrated pressure and flow monitoring, the system ensures consistent performance with real-time data acquisition to support robust process control.

The single-pass TFF step is a key component of our fully integrated continuous nanoparticle manufacturing process. DIANT’s focused process begins with precise mixing and encapsulation, followed immediately by single-pass TFF-forming a seamless continuous workflow. This platform is particularly well-suited for applications involving lipid nanoparticles, mRNA formulations, and protein therapeutics, and is designed with scalability and in-line process analytics in mind.