The functionalities of a paper-PDMS hybrid microchannel, as a potential fluidic transport platform, are presented. The setup consists of a PDMS microchannel with one of its walls covered by paper. In contrast to the available microfluidic platforms, the capillary filling is found to occur at much faster speed in the hybrid channel. Moreover, experimentation using two dye solutions shows mixing enhancement at a significantly faster rate and at a shorter distance in the hybrid channel as compared to the other available counterparts. The paper attachment is found to induce an effective slip during liquid transport, and thereby allows faster transport and capillary filling. The liquid slippage further modifies the shear flow behavior near the wall leading to a slip-enhanced mixing within the hybrid channel. These fundamental understandings correspond to the experimental results quantitatively in terms of corroborating scaling laws. Further mixing enhancement is introduced through spiral, curved and elliptical–spiral geometries of the channel. Apart from the above benefits, the enclosed arrangement protects sensitive reagents from external environment and offers better control over their transport, thus giving a stable mixing and reaction performance inside the channel.

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Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis (MTb) and is one of the majorcauses of death in the world. One third of the population suffers with TB and there is no potential drug introduced in the past 5 decades. The drugs currently used are ineffective due to the emergence of MDR (Multidrug Resistant Strain), XDR (Extreme Drug Resistant strain) and other co-infections. Hence there is a need for a potent molecule that can inhibit the growth of mycobacterium effectively. The plant kingdom provides a large variety of naturally occurring phytochemicals and other secondary metabolites which are known to be antibacterial. Therefore the present study focuses on screening and identification of potent antimycobacterial plants. Various parts of the plant including leaves are traditionally used for treating a wide spectrum of diseases. In the screening studies of dry leaf (methanolic extracts) of plants from the Western Ghats region gave rise to two potent anti-mycobacterial plants. These plants were identified as TithoniadiversifoliaHemsl.A. Gray(TD) and CouroupitaguianensisAubl. (CG). Both TD and CG plants showed significant anti-mycobacterial activity conducted by well diffusion assay having clearance zone of 15.6 mm and 17.3 mm respectively. These plant extracts were further purified with polar solvents and potential antimycobacterial extracts were tested for their minimum inhibitory concentrations (MICs). The MICs for TD ethyl acetate extract and CG chloroform extract were reported as less than 64µg/ml and 64µg/ml respectively. The entire investigation of anti-mycobacterial study was conducted against Mycobacterium smegmatis whichis a model organism for mycobacterial studies. These results show that both plants contain potent anti-mycobacterial compound(s) that can be further investigated for purification and isolation of bioactive compound which can be useful in the production of novel drugs.