Permeability assessment of hydrogen peroxide through home elastomeric infusion pump devices after gas sterilisation in isolator
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78105 St Germain en Laye – France
Our objective was to check permeation risk through 4 different elastomeric infusion pumps using a previous validated colorimetric method  using spectrophotometric detection of oxidation reaction with peroxyde (peroxykit®, Sigma).The samples were prepared following protocol (i) pre-filling of the device with water for injection-Re-sealing in the original overwrapping-Gas sterilisation then followed by immediate analysis. All devices were exposed to 3 successive gas sterilisation cycles with Perform® select Soproper, Schülke, France which is a blend of peracetic acid 3.5% and hydrogen peroxide 30% during 70 minutes in isolator pass through hatch of 0.2m3 with STELEC steriliser, JCE Biotechnology, France. The results are given in the table1 :
The results are highly dispersed and, within a sterilisation cycle and with a same device, very high variations have been registered explaining the standard deviations observed. As a matter of fact, it seems that the first cycle of sterilisation is low risk for gas permeation, except for Accufuseur® but re-sterilisation of the devices has to be clearly avoided. Taking into consideration that the protocol used could introduce a bias in the permeation process due to the pre-filling of the empty device, we conducted a complementary study assessing the permeation through empty devices, bag and Accufuser® following a new protocol (ii) Gas sterilisation of the empty device, immediate filling with water for injection after sterilisation cycle and analysis at T0 and T24h after exposure. The results are given in the table 2 : Permeation result of H2O2 (µg/l) with regards to protocol (i) and (ii)
With regards to our results, the protocol (i) favoured the detection of gas permeation whereas protocol (ii) enabled to reproduce the real conditions of exposure of the empty devices and showed the permeation of only traces, with results below the quantification limit. Protocol (ii) is much more in accordance with qualification process ensuring a low risk for routine use of the empty devices in isolator. Nevertheless, protocol (i) corresponds to real conditions for pre-filled bags of diluents ; and can explained the permeation previously observed when the bags were not over-wrapped .
 Edet S et al., Permeation of the sterilising agent in bags : a simplified routine evaluation method. GERPAC 2010 Presqu’île de Giens, France