HomeBlogSterilizing filtration – Upgrade

Sterilizing filtration – Upgrade


An important injectable producer from Romania expressed the interest to optimise the costs for sterilizing filtration step for one of their main products.

Taking into consideration that technology nowadays evolves, an analyse of the sterile filtration validation can help the process.

Our customer wants to analyse the filtration step of the process in order to establish if the prefilter can be excluded from the process and include in its place a new filter media cartridge with double role, prefilter and sterile filtration, in order to help for cost reduction and process efficiency.


Filtration process for one batch takes around 380 minutes due to product viscosity so the aseptic process line is blocked. So one filter cartridge with larger filtration surface can be suitable to reduce the process time.

The microbial load of the product it is not high, so we considered to perform some trails with only one filter cartridge able to fulfil the prefiltration and sterile filtration too.

The costs may diminish if the results will show that one filter cartridge can filter one batch in the same process time or even less.


We tested the proposed filter media for one full batch of product without active principles.

The first filter housing was empty and in the second one was placed the sterilizing grade filter cartridge with an asymmetric membrane including prefilter role and the filtration step started (1st image).

Process parameters (temperature, pressure drop on the filter media, time) were monitored for the full filtration step using the manometers placed on the housing, on the preparation tank (2nd image) and with the integrated software.

The pressure drop during the filtration step for the whole 420L batch was 400 mbar maximum, meaning the filter media was not fully used.

The product was filtered in 47 minutes and collected in the storage tank (3rd image).


  • Filtration time improvement with around 5 hours and 30 minutes.
  • Proposed filter media was not fully used so it can resist for a larger production batch or for working in campaign.
  • Costs optimisation considering using only one filter cartridge with double role and lower product process time.
  • Aseptic filtration line available for longer period.
  • The results will be analysed by our customer to budget a new validation service for sterile filtration with our partner support, Pall Corporation.