Microfluidic paper-based analytical devices (µPADs) have provided a breakthrough in portable and low-cost point-of-care diagnostics. Despite their significant scope, the complexity of fabrication and reliance on expensive and sophisticated tools, have limited their outreach and possibility of commercialization. Herein, we report for the first time, a facile method to fabricate µPADs using a commonly available laser printer which drastically reduces the cost and complexity of fabrication. Toner ink is used to pattern the µPADs by printing, without modifying any factory configuration of the laser printer. Hydrophobic barriers are created by heating the patterned paper which melts the toner ink, facilitating its wicking into the cross-section of the substrate. Further, we demonstrate the utilization of the fabricated device by performing two assays. The proposed technique provides a versatile platform for rapid prototyping of µPADs with significant prospect in both developed and resource constrained region.

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Equilibrium Uptake and Bioaccumulation of Basic Violet 14 Using Submerged Macrophyte Hydrilla verticillataThe percentage removal and uptake capacity of Basic Violet 14 using Hydrilla verticillata with living biomass was studied under batch conditions. The survival of H. verticillata was studied using the chlorophyll content in the living biomass. Bioaccumulation of Basic Violet 14 using H. verticillata was tested by varying the wet sorbent dosage (0.5-2.5 g), initial pH (3-8), and initial dye concentrations (5-25 mg L À1 ). The results show that the plant was effectively accumulating the Basic Violet 14 dye. The uptake capacity of Basic Violet 14 dye was observed as 5.9 and 21.3 mg g À1 at the initial dye concentration of 5 and 25 mg L À1 , respectively, for a biomass of 5 g L À1 (wet weight) at pH 7.0 for 144 h. In general, the plant growth was found to be normal at lower concentrations and showed higher removal efficiency. It was also observed that removal efficiency of H. verticillata was found to decrease with increase in initial dye concentration. The biomass sample surface was analyzed using SEM imaging and functional groups present in the biomass were analyzed using FTIR. The equilibrium uptake capacity was analyzed by Langmuir and Freundlich isotherms. The equilibrium data was found to be fit well to both Langmuir and Freundlich isotherm models with higher coefficient of determination. In the last decades, the use of phyto-technologies has become an effective alternative method for the remediation of contaminated water systems [5]. Phytoremediation is defined as the use of plants, both terrestrial and aquatic; to absorb, concentrate, and precipitate contaminants from polluted aqueous sources with low contaminant concentration in their roots [6]. The U.S. Environmental Protection Agency (EPA) seeks to protect human health, environment associated with hazardous waste sites, and encourages the development of innovative technologies such as phytoremediation to clean up hazardous sites [7].Most of the work has been already established on the accumulation of heavy metal using plant such as Hydrilla verticillata for cadmium accumulation [8], Pistia stratiotes for arsenate uptake [9], Wolffia globosa for an indicator of metal pollution in the water bodies [10], P. stratiotes for lead uptake [11]. Only limited work has been established for the removal of textile dyes using living aquatic plant. In this present study, H. verticillata was used as living biomass for the accumulation of basic dye from synthetic dye solution.Basic dyes are salts of the colored organic bases containing amino and imino groups and also combined with a colorless acid, such as hydrochloric or sulfuric acid. They are brilliant and most fluorescent among all synthetic dyes. Basic Violet 14 was selected as a model compound to estimate the accumulation capacity of H. verticillata. It is a submerged plant, and it has been observed to grow luxuriantly in various contaminated water bodies of India [12]. H. verticillata has attracted the attention ...

Passive release of fungal spores can occur from various natural and anthropogenic sources leading to significant concentrations in ambient air with potential effect on health and climate. The estimation of fungal spore release is a critical parameter necessary for the realistic assessment of health risk using dispersion models and in global climate modeling. This paper presents results from experiments conducted to seek a better understanding of the process of passive fungal spore due to wind. Laboratory studies were conducted to measure emission fluxes of a test fungal species (Penicillium chrysogenum) grown on two test surfaces (aluminum foil and cardboard) in a flux chamber in response to air flow. Spore growth on the aluminum foil correlated with the amount of nutrient, while for cardboard, fungal growth was observed just with the presence of water without any external nutrients. The released spores were collected using a commercially available impinger (Biosampler ® ) and quantified using fluorescence microscopy. Spore flux correlated positively with the number of spores on the surface and with air velocity above a threshold velocity. Fungal spore flux decreased on continuous exposure to air. Microscopic inspection of the surface revealed that the normally upright hyphae bearing the fungal spores collapsed after exposure to air thus suggesting that the decrease in flux was due to a decrease in the aerodynamic drag on the spores. Fungal hyphae also collapsed when there was depletion of nutrients for spore growth leading to reduction in flux. A preliminary mathematical model that estimates spore flux based on the energy transfer between the air and the fungal spores and the energy required to remove the spores is presented. A characteristic energy parameter for aerosolisation was obtained from the model fit. Using this parameter, the model predicted experimental fluxes under various conditions reasonably well.