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EP-4178354-B1 - TWO-PART DISINFECTANT SYSTEM COMPRISING A COLOUR INDICATOR

EP4178354B1EP 4178354 B1EP4178354 B1EP 4178354B1EP-4178354-B1

Inventors

  • BRAND, THOMAS

Dates

Publication Date
20260506
Application Date
20210713

Claims (9)

  1. A disinfectant system comprising: (a) a first part comprising a first reagent in a carrier medium; and (b) a second part which is miscible with the first part and which comprises a second reagent in a carrier medium; wherein the first reagent and the second reagent will react when the first and second parts are mixed to provide a chlorine dioxide disinfecting composition; characterised in that the first part or the second part further comprises a dyestuff that oxidises in the presence of chlorine dioxide to produce a visible colour change upon mixing of the first part with the second part; wherein said colour change does not occur upon exposure of the dyestuff-containing part to a hydrogen peroxide disinfectant and/or a peracetic acid disinfectant; wherein the dyestuff is an anthocyanin dyestuff selected from the group consisting of purple carrot extract, haskapa berry extract, blackcurrant extract, and black carrot extract, or an anthocyanidin dyestuff selected from the group consisting of bilberry extract and blue pea extract, or a betanin dyestuff selected from the group consisting of red beetroot powder and beetroot juice concentrate.
  2. A disinfectant system according to Claim 1, wherein the dyestuff changes from coloured to colourless in the presence of chlorine dioxide.
  3. A disinfectant system according to Claim 1 or Claim 2, wherein the first reagent comprises a metal chlorite and the second reagent comprises an acid.
  4. A disinfectant system according to any of the preceding claims, wherein the first part is contained in a dispenser whereby it may be dispensed as a fluid.
  5. A disinfectant system according to any of the preceding claims, wherein the second part is absorbed or impregnated in at least one wipe (16).
  6. A disinfectant system according to any of Claims 1 to 4, wherein the first part and the second part each comprise liquids.
  7. A disinfectant system according to any of Claim 1 to 4, wherein the first part and the second part each comprise foams.
  8. A disinfectant system according to any of the preceding claims, wherein the second part comprises the dyestuff.
  9. A disinfectant system according to any of the preceding claims, wherein the first part or the second part comprises between about 0.1 wt% and about 2 wt% of the dyestuff.

Description

BACKGROUND a. Field of the Invention The present invention relates to a disinfectant system, notably to a system for preparing chlorine dioxide using a two-part chemistry. The invention is particularly for use in disinfecting medical devices and surfaces, notably surfaces in clinical environments, but it is not limited to these uses. b. Related Art Two-part disinfectant systems which produce chlorine dioxide when mixed are known. Such systems typically include a chlorite and an acid, or a chlorate, a reducing agent and an acid. WO 2005/011756 discloses a two-part disinfecting system (shown in Figure 1). The disinfecting system 6 comprises a first part having a first reagent in a carrier medium and a second part which is miscible with the first part and which comprises a second reagent in a carrier medium. The first reagent and the second reagent react when mixed to provide a disinfecting composition. The first part is contained in a pump dispenser 2 whereby it may be dispensed as a fluid, preferably as a foam, and the second part is absorbed or impregnated in at least one fabric member in a sealed container 4. To prepare a disinfecting wipe, a user removes an impregnated wipe from the container, and applies a portion of foam from the sprayer to the wipe. To facilitate mixing of the reagents in the foam and the wipe, the user may fold the wipe in half and crush or rub the folded wipe before opening it out. WO 2005/107823 describes a system (shown in Figure 2) suitable for the reprocessing of non-lumened medical devices using a manual three-wipe disinfection process. An example system includes a box 10 containing sachets 8 of pre-clean wipes, a disinfecting system 6 as discussed above, and a box 14 containing sachets 12 of sterile rinse wipes. The pre clean wipe is used to wipe an item such as an endoscope which is to be decontaminated. The two-part disinfecting system 6 (combination of a wipe and activator foam) is used for sterilising or disinfecting the item and the sterile rinse wipe is used to remove any chemical residue. All disinfection details can be recorded in an accompanying audit trail book to allow full procedural traceability. WO 2006/079822 A1 describes another disinfecting system. In this case the first and second reagents are each carried in aqueous media to which foam promoters are added, so that both the first and second parts of the system are dispensed as first and second foams respectively. The first and second foams are mixed to generate the disinfecting composition, which may then be applied to an item or surface to be disinfected directly or with a wipe. WO 02/091832 A1 describes another two-part disinfecting system, where the two parts are adapted to be mixed to yield an aqueous disinfecting composition. The first part comprises a chlorite and the second part comprises an acid. The composition further comprises an alpha olefin sulfonate to suppression chlorine dioxide formation. GB 2 413 765A discloses a two-part disinfectant system, which corresponds to the system described in present figure 1. The dye used is a pH-sensitive dye, different from the dyes used in the present invention. JP 2016 113354 A discloses a two-part disinfectant system, in which the indicator, different from the dyes of the present system, is oxidized by chlorine dioxide. To ensure full effectiveness of a disinfectant wipe or other chlorine dioxide disinfecting system, it is desirable to ensure that chlorine dioxide has been generated and that the action of generating chlorine dioxide can be verified by the end user. It has been proposed to include in one of the components a pH-sensitive indicator which changes colour or becomes coloured when adequate mixing has occurred. A problem with this approach is that pH may not change much, or a change in pH may not reliably correlate with generation of sufficient chlorine dioxide. As the medical industry develops there are pressures to move towards automated disinfection systems that are perceived to provide additional assurances that the disinfection process has been successfully completed. The primary arguments in favour of these systems are that they eliminate or reduce the probability of user error and can provide a digital ticket at the end of a machine cycle. Currently available technologies include test strips, odour detection, titrations and spectrophotometry. Although all able to determine chlorine dioxide concentration they are limited by accuracy of measurement (with some methods semiquantitative), the requirement for a laboratory facility and the impingement on the natural process flow of device reprocessing. SUMMARY OF THE INVENTION Aspects of the invention are specified in the independent claims. Preferred features are specified in the dependent claims. By incorporating a suitable dyestuff in one of the parts of the system, it is possible to verify, either by eye or by opto-electronic means, that chlorine dioxide has been produced at an efficacious level