Clevertex - Grado Zero Espace Srl

Currently, there is no commercial product available
Recently, the firm Procter & Gamble announced their intention to launch an intelligent slip on the
market. The aim is to notify the female wearer when ovulation is coming or when she will start to
menstruate.
To determine the ovulation, a layer of silicones is used covered with a thin plastic film. The silicones
react to hormonal changes that are characteristic for the ovulation period and expand a little. The
small thickening modifies the refraction of the light, resulting in a violet dot on a golden background.
To determine the menstruation period, two indicators are necessary. In the first place, a resin is used
which turns blue at the presence of the smallest trace of blood. The second product is an acid which
turns red at a pH between 4 and 7. These two indicators together give a purple colour, approximately
four hours before the start of the menstruation.
Benjamin Miller and colleagues of the University of Rochester, New York State, US, have developed a
sensor that generates an easy recognizable array of colours that signify dangerous or antibioticresistant
strains. So far, the device produces only a very small colour change, which is not detectable
with the naked eye.
Most bacteria are either Gram-positive or Gram-negative. A dye called crystal violet stains Grampositive
bacteria blue-violet and Gram-negative bacteria red. This staining procedure was discovered
in 1884 by the Danish biologist Christian Joachim Gram and is still used today to distinguish the two
cell types. Miller’s team hope to replace the cumbersome staining procedure with a simple process
that registers the difference instantly and in situ. Therefore they will use silicon-based light-emitting
devices. When Gram-negative bacteria stick to the surface of porous silicon, the colour of the light
emitted changes slightly. the researchers make the silicon attract Gram-negative, but not Grampositive
bacteria, by coating it with specially designed molecules that hook chemicals groups only
present on Gram-negative microbes.
Eventually this may lead to the development of smart bandages that could soon alert doctors to the
presence of certain bacteria in a wound by glowing different colours.
131