Harnessing electrochemical energy in an engineered electrical circuit from biochemical substrates in the human body using biofuel cells is gaining increasing research attention in the current decade due to the wide range of biomedical possibilities it creates for electronic devices. In this report, we describe and characterize the construction of just such an enzymatic biofuel cell (EBFC). It is simple, mediator-free, and glucose-powered, employing only biocompatible materials. A novel feature is the two-dimensional mesoporous thermally reduced graphene oxide (rGO) host electrode. An additionally novelty is that we explored the potential of using biocompatible, low-cost filter paper (FP) instead of carbon paper, a conductive polymer, or gold as support for the host electrode. Using glucose (C 6 H 12 O 6 ) and molecular oxygen (O 2 ) as the power-generating fuel, the cell consists of a pair of bioelectrodes incorporating immobilized enzymes, the bioanode modified by rGO−glucose oxidase (GOx/rGO), and the biocathode modified by rGO−laccase (Lac/rGO). Scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/ EDX), transmission electron microscopy, and Raman spectroscopy techniques have been employed to investigate the surface morphology, defects, and chemical structure of rGO, GOx/rGO, and Lac/rGO. N 2 sorption, SEM/EDX, and powder X-ray diffraction revealed a high Brunauer−Emmett−Teller surface area (179 m 2 g −1 ) mesoporous rGO structure with the high C/O ratio of 80:1 as well. Results from the Fourier transform infrared spectroscopy, UV−visible spectroscopy, and electrochemical impedance spectroscopy studies indicated that GOx remained in its native biochemical functional form upon being embedded onto the rGO matrix. Cyclic voltammetry studies showed that the presence of mesoporous rGO greatly enhanced the direct electrochemistry and electrocatalytic properties of the GOx/rGO and Lac/rGO nanocomposites. The electron transfer rate constant between GOx and rGO was estimated to be 2.14 s −1 . The fabricated EBFC (GOx/rGO/FP-Lac/rGO/FP) using a single GOx/rGO/FP bioanode and a single Lac/rGO/FP biocathode provides a maximum power density (P max ) of 4.0 nW cm −2 with an open-circuit voltage (V OC ) of 0.04 V and remains stable for more than 15 days with a power output of ∼9.0 nW cm −2 at a pH of 7.4 under ambient conditions.

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Background: Pregnancy is a physiological status of a woman. Every organ is adapting in order to accept another human body. Many skin changes during pregnancy are considered to be normal or physiological but few dermatoses occurring in pregnancy may severely affect the mother as well as the fetus. Early diagnosis and treatment may help to reduce morbidity and mortality to the gravid patient and her fetus and minimize fetal exposure to unnecessary treatment. Objective: To determine the pattern of dermatoses during pregnancy. Materials and Methods: One hundred sixteen pregnant women of different trimester were selected out of 1674 according to the exclusion and inclusion criteria for this study. Detailed history, clinical examination and relevant investigations were done in all patients. Results: This clinical study shows about 6.9% pregnant women had specific dermatoses. Maximum 44(37.9%) women were in between the age of 25 to 29 years. According to trimester 69(59.48%) patients were in third trimester. In case of gravid maximum 68(58.62%) patients were primigravida. In this study pruritic urticarial papules and plaques of pregnancy (PUPPP) was the most common dermatoses during pregnancy. Conclusion: A pregnant woman with a pruritic skin eruption requires immediate evaluation and diagnosis because delayed diagnosis or misdiagnosis may pose significant risk to the fetus and the mother. It is necessary to know how to diagnosis and treat this condition to establish a better outcome for the mother and the fetus. Sir Salimullah Med Coll J 2022; 30: 46-50