Papers by nithya murugesan
2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC), 2015
Motile bacteria respond to changing chemical environment by moving towards or away from a particu... more Motile bacteria respond to changing chemical environment by moving towards or away from a particular location. Bacterial migration under chemical gradient is one of the most studied areas in biomedical field. In this work we looked into how bacterial cells respond to sudden change in the microfluidic chemical environment. E.coli DH5α cells were subjected to an attractant gradient (0.1 mM sorbitol - attractant to E.coli cells) and after 120 min the same cells were exposed to an inhibitor (0.1 mM NiSO4) gradient in the same microfluidic device. Our studies revealed that when the E.coli DH5α cells were exposed to 0.1 mM sorbitol, they showed faster chemotaxis towards the attractant (0.1 mM sorbitol) and achieved steady state by 60 min. When we replaced 0.1 mM sorbitol with 0.1 mM NiSO4 in the device we found that that the E.coli DH5α cells started responding to change in chemical environment within 10 min and achieved steady state at the end of 60 min. This shows that the bacterial cells respond to change in local chemical environment is within few minutes.
Biomicrofluidics, 2017
Living systems are constantly under different combinations of competing gradients of chemical, th... more Living systems are constantly under different combinations of competing gradients of chemical, thermal, pH, and mechanical stresses allied. The present work is about competing chemical and thermal gradients imposed on E. coli in a diffusive stagnant microfluidic environment. The bacterial cells were exposed to opposing and aligned gradients of an attractant (1 mM sorbitol) or a repellant (1 mM NiSO4) and temperature. The effects of the repellant/attractant and temperature on migration behavior, migration rate, and initiation time for migration have been reported. It has been observed that under competing gradients of an attractant and temperature, the nutrient gradient (gradient generated by cells itself) initiates directed migration, which, in turn, is influenced by temperature through the metabolic rate. Exposure to competing gradients of an inhibitor and temperature leads to the imposed chemical gradient governing the directed cell migration. The cells under opposing gradients of...
Waste-to-Energy Approaches Towards Zero Waste
Journal of Micromechanics and Microengineering
Uploads
Papers by nithya murugesan