 mM) /aqAgB ( AgB 3 C  mM) for about 6 hours, resulting in the generation of AuNPs or AgNPs at the aqueous salt/PDMS interface. The NPs were peeled off using a commercially available transparent tape, which was then cut into small pieces and added to a pool of (50 ml) of Acetone. The solution was then stirred at 600 rpm at 50°C for 4 hours. The solution was sonicated for 60 minutes, followed by drop casting on standard TEM grid (carbon coated copper grid). It was then dried for twenty minutes beneath a lamp and then examined under FEI-Titan G2 60-300 KV TEM to capture the image of NPs. ). Both these values closely match with that estimated from the contact angle method. Furthermore, the deformation of the skin remains unaltered over time, so long as the same liquid remains filled within the channel. In Fig. , with degassed water inside the channel, the deformation of the skin remained unaltered for @1 hour. To examine, if the elastocapillary effect described above, can be used to relate the solute concentration in a liquid to the deformation of channel wall, Ethanol (surface tension,   mN/m) was mixed with water to different extent (aqEth), and was inserted into a typical channel. The surface energy of these liquids was measured using pendant drop method (Fig. ). Fig. ). For Gold salt, metallic NPs appear as per the following surface reaction: