Research

The main research focus of our lab is quantitative force measurements in the range of pN to nN to study various aspects of molecular mobility, dynamics and mechanical response at single molecular scale. Our goal is to develop new methods with spatial resolution at molecular scale and time resolution of few tens of microseconds.

Nano-mechanics of lipid bi-layers and cell membrane

The mechanics at nano-scale is not only important for materials science involving single crystals and high strength alloys, but it is also relevant for biomaterials. Currently we are measuring mechanical response of tethers pulled from supported lipid bi-layers and cell membranes to measure molecular level responses to external mechanical disturbance. The goal is to identify common features on both cells and supported bi-layers which can be attributed to membrane-water interaction rather than the complicated physiology of the cell. We use Atomic Force Microscope, a technique having unprecedented spatial (< nm) as well as force resolution (< pN) in these investigations.

Confined liquids

Confined liquids are relevant in variety of areas such as lubrication of nano-scale devices, interfacial water in cell biology and nano-fluidics. A liquid that is restricted to move in nanoscale confinement is an interesting class of materials. The direct consequence of such confinement is reduced mobility of liquid molecules, enhanced viscosity and confinement induced ordering of liquid. We are building an instrument to study molecular mobility under confinement. (Project funded by DST nanomission)

Biosensors

AFM cantilevers can weigh masses less than picograms. Further, the adsorption of these masses such as bio-molecules, gas molecules generate a differential stress on the lever which can be measured for biosensors application. We are working on using similar methods employing micro-machined tuning forks which can provide better sensitivity with an electrical read-out. This can become an important tool in de-centralized diagnostics as well as a target validation. (Project funded by Wellcome DBT India alliance)

Single protein molecules under stress

We are building new techniques to measure response of single molecules under controlled stress. We propose to combine spatial resolution of probe microscopic techniques with temporal resolution of correlation spectroscopy. (Project funded by Wellocme-DBT India alliance )