Charge density alterations in human hair fibers: an investigation using electrostatic force microscopy

V M Longo1, V F Monteiro, A S Pinheiro

  • 1CMDMC/LIEC/DQ/DEMA/UFSCar, Universidade Federal de São Carlos, São Carlos, SP 13565-905, Brazil. valerialongo@liec.ufscar.br

Related Concept Videos

Electric Charges01:11

Electric Charges

From lightning during thunderstorms to electronic devices, the phenomenon of electromagnetism is all around us. The electromagnetic force is one of the four fundamental forces of nature. It has been known to humanity in various forms for thousands of years. For example, the ancient Greek philosopher Thales of Miletus recorded his experiments on static electricity using amber and fur in the sixth century BC.
The English physicist William Gilbert studied the phenomenon of static electricity in...
Accessory Structures of the Skin: Hair and Hair Follicles01:16

Accessory Structures of the Skin: Hair and Hair Follicles

Hair and hair follicles are integral components of the integumentary system. Hair is a filamentous structure composed mainly of a protein called keratin. It is found on the surface of the skin throughout the body, except for areas such as the palms of the hands and soles of the feet.
Hair is a keratinous filament growing out of the epidermis. It is primarily made of dead, keratinized cells. Hair strands originate at the epidermal penetration called the hair follicle. The hair shaft is the part...
Studying the Cytoskeleton01:17

Studying the Cytoskeleton

The cytoskeletal architecture can be studied using different microscopic and biochemical techniques. Electron microscopy was instrumental in discovering the cytoskeletal architecture around the 1960s, which allowed obtaining structural information at a high-resolution level. However, the sample preparation procedure often limits this ability in biological samples. Several protocols have been developed over the years to optimize sample preparation. In one of the protocols known as rotary...
The Electrical Double Layer01:30

The Electrical Double Layer

In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...
Current Density01:21

Current Density

The total amount of current flowing through one unit value of a cross-sectional area is referred to as current density. If the current flow is uniform, the amount of current flowing through a conductor is the same at all points along the conductor, even if the conductor area varies. The current density consists of the local magnitude and direction of the charge flow, which varies from point to point. Current density is measured in amperes per meter square, and direction is defined as the net...
Capillary Electrophoresis: Instrumentation01:20

Capillary Electrophoresis: Instrumentation

Capillary electrophoresis instrumentation typically consists of several key components. A high-voltage power supply generates the electric field necessary for the separation by connecting to an anode (the positively charged electrode) and a cathode (the negatively charged electrode) located in buffer reservoirs at each end of the capillary tube. The system includes a sample vial, a fused silica capillary tube coated with polyimide for mechanical strength through which the sample components...