Multi-Stage Liquid Impinger (MSLI)

The Multi-Stage Liquid Impinger (MSLI) is a versatile five-stage liquid impinger which can be used for determining the particle size (aerodynamic size distribution) of DPIs in the case of USP Chapter <601> and for MDIs, DPIs and nebulisers in the case of Ph.Eur. Chapter 2.9.18.

The MSLI is available in a range of materials: aluminium, 316 stainless steel or titanium. This choice allows flexibility in terms of corrosion resistance, weight and cost. It is fitted with PTFE seals as standard.

The design is such that at a flow rate of 60 L/min, the cut-off diameters of Stages 1, 2, 3 and 4 are 13, 6.8, 3.1 and 1.7 microns. Stage 5 comprises an integral paper filter to capture the remaining fraction of particles less than 1.7 microns.

The MSLI has, by definition, no inter-stage losses and is suitable for use throughout the range 30 – 100 L/min. Unlike the ACI, NGI and MMI, the collection stages of the MSLI are kept moist which helps to reduce the problem of re-entrainment sometimes experienced when using more conventional impactors. It employs the same induction port as other impactors.

For comprehensive product details, specifications and part numbers, please request a copy of our brochure “Quality Solutions for Inhaler Testing”.