Black pigment cells called melanophores change colour in response to environmental changes and have lately been studied as promising biosensors. To further elucidate the intracellular processes involved in the colour changes of these cells, and to find optimal biosensing principles, the electric charge of intracellular pigment granules, melanosomes, has been determined in vitro by electrophoresis. Melanosomes from the two extreme states in the cell colour change (aggregated and dispersed melanosomes) were measured. The charge was found to be -1.5 x 10(-16) and -1.7 x 10(-16) C, aggregated and dispersed melanosomes, respectively, without significant difference between the two conditions. This charge is of the same order of magnitude as the one of 1000 electrons. The origin of the melanosome charge, and the use of these findings in new biosensor principles, is discussed.
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http://dx.doi.org/10.1016/s0956-5663(00)00130-5 | DOI Listing |
ISA Trans
January 2025
Tenaga Nasional Berhad - Distribution, Kuala Lumpur, Selangor, Malaysia. Electronic address:
As global interest grows in renewable energy sources, the impact of combined Electric Vehicle (EV) and PhotoVoltaic (PV) penetration on the power grid stability requires renewed attention, to incorporate new technologies to maintain the power quality under operational constraints. Energy-saving techniques such as Conservation Voltage Reduction (CVR) allow the power utilities to transmit voltage at a lower operation limit, increasing the generation margin to absorb the peak load demands. Increased reverse PV penetration results in grid overvoltage while EV charging absorbs the reactive power causing grid instability.
View Article and Find Full Text PDFACS Nano
January 2025
State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
Pulsatile ion transport facilitates the adjusted transfer of substances, meeting the requirements for the gradient and timed separation of multiple components in membrane processes. Responsive nanofiltration membranes are thus currently receiving widespread attention but face limitations due to their narrow performance adjustment range. Herein, hydroxyl functional groups were introduced into electrically responsive nanofiltration membranes to broaden the adjustment range of separation performance through a combination of pore size sieving and functional group interactions, resulting in a greater change in rejection and flux compared to the original membrane.
View Article and Find Full Text PDFSci Total Environ
January 2025
Department of Geosciences & Natural Resource Management, Geology, University of Copenhagen, Denmark.
Due to increasing plastic production, the continuous release of primary and secondary nanoplastic particles (NPs, <1 μm) has become an emerging contaminant in terrestrial environments. The fate and transport of NPs in subsurface environments remain poorly understood, largely due to the complex interplay of mineralogical, chemical, biological, and morphological heterogeneity. This study examines interactions between abundant subsurface minerals and NPs under controlled water chemistry (1 mM KCl, pH 5.
View Article and Find Full Text PDFNanotechnology
January 2025
Qingdao University, Ningxia Road 308, Qingdao, Shandong, 266071, CHINA.
Graphitic carbon nitride (g-C3N4) has gained significant attention as a promising nonmetallic semiconductor photocatalyst due to its photochemical stability, favorable electronic properties, and efficient light absorption. Nevertheless, its practical applications are hindered by limitations such as low specific surface area, rapid recombination of photogenerated charge carriers, poor electrical conductivity, and restricted photo-response ranges. This review explores recent advancements in the synthesis, modification and application of g-C3N4 and its nanocomposites with a focus on addressing these challenges.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Chemical Engineering, University of Florida, Gainesville, FL 32611.
We describe a microfluidic device to extract DNA from a cell lysate, without the need for centrifuges, magnetic beads, or gels. Instead, separation is driven by transverse migration of DNA, which occurs when a polyelectrolyte solution flowing through a microfluidic channel is subjected to an electric field. The coupling of the weak shearing with the axial electric field is highly selective for long, flexible, charged molecules, of which DNA is the sole example in a typical cell lysate.
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