FPLC Explained

Fast Protein Liquid Chromatography or FPLC (formerly called Fast Performance Liquid Chromatography) is an advanced technique used in biochemistry and molecular biology to separate, and sometimes purify, biomolecules, in particular, proteins. As with other types of liquid chromatography, FPLC employs a liquid mobile phase and a fixed stationary phase. The mobile phase, containing the molecules of interest, runs through the stationary phase which consists of one or more specialized resins or matrices responsible for the chromatographic separation. In addition, the flow rates and elution conditions in FPLC are all controlled automatically through a system of pumps, interconnecting tubes, and columns to achieve the desired result. In fact, FPLC is similar to a better known type of liquid chromatographic technique called High Performance Liquid Chromatography or HPLC. However, FPLC operates at relatively low pressure but with a relatively fast flow rate, which is the reverse of how HPLC works. Significantly, FPLC is pivotal for various downstream applications in medical diagnostics and scientific research. 

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The Mechanics Behind Measuring Electrical Conductivity of Solutions

Electrical conductivity of a solution refers to its ability to conduct electric current. The metric is used in several real-world applications including the monitoring of water supplies for purity, and when measuring the concentration of plant nutrients in a feed solution. It is also a component of some scientific tools like Fast Protein Liquid Chromatography (FPLC) where it is used to monitor the ionic strength of the mobile phase or buffer.  

Electrical conductivity occurs because of the presence of charged ions within a solution. Applying an electric potential across the solution causes the charged ions to migrate towards their respective oppositely-charged electrodes. As a result, the flow of ions mediates the passage of the electric current. Significantly, the conductivity level of the solution depends on a number of factors, the main ones being the concentration of ions in the solution as well as its temperature.

In this post, we investigate the units normally used to quantify this electrical phenomenon, how to actually measure the conductivity of solutions, and finally, its relationship to the TDS metric.

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Thermionic Emission

Thermionic emission is the process whereby charged particles (usually electrons), known as thermions, are emitted from the surface of a heated material, usually a metal. The process is driven by the extra thermal energy that is added to the system. As a result, energised electrons can overcome the surface barrier of the material and escape into the surrounding space. This phenomenon has been used in various applications, including vacuum diodes, cathode ray tubes and, more recently, mass spectrometry. 

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Repairing the AA Car Battery Solar Trickle Charger

The AA Car Battery Solar Charger is a perfectly good solar panel for ensuring that your car battery does not run down if the vehicle is not used often enough. Its one weakness, however, is the cable coming out of the solar panel, which is prone to breaking, in part because the gauge of the internal copper wire is so thin. Worse still, it is all too easy for a wire break to go unnoticed, since the cable's insulation can remain intact, and the blue flashing LED on the solar panel will continue to flash irrespective of whether the car battery is being charged or not. Consequently, if a wire break does occur inside the cable, there is a good chance you will be unaware of the problem and one day when you try to start your car - it won't! I encountered this very problem...and this is how I fixed it.

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Wireless Weather Station Reviews for the UK

​Weather for us Brits is a big part of our daily lives - not surprising since our weather can be often so unpredictable. Many of us too are fascinated by the weather, its unpredictability, ​its variability from year to year, and with global warming entering into the equation and making weather more extreme, it is only going to get all the more​ wild and interesting. That is why more and more of us are getting into monitoring our local weather not only to make better decisions in our own personal lives but also to ​keep track of how ​our weather is changing over time. One of the weather monitoring tools that is within almost everyone's budgetary reach is the wireless home weather station, which ​usually consists of a central display unit with one or more wireless sensors ​sited around and outside the home. Of course, as with all electronic gadgets these days, the humble weather station exists in a ​plethora of different makes and models, each sporting a range of different features, ​making the choosing of the best weather station for the home a difficult and confusing task. That's why here at Approach Labs, we have taken the time to look into the variety of features that different home weather stations ​offer, and to compare the popular ​ones that are available to consumers here in the UK​ to help you decide what's the best wireless weather station to buy for your particular home.

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Taotronics Mobile Phone / GPS Car Holder Permanent Mount

Summary: If you are the owner of a Taotronics car phone holder and, like me, you like the design and functionality it provides, but dislike suction cup attachments in general and the fact that it occassionally falls off the windscreen when the weather is warm, then check out this project where I convert the suction cup mount into a permanent mount for my car's dashboard. Super-steady and no more messing around with the unpredictability of suction cups. Looks good too, although would have preferred it in black!

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A Simple Programming Board for the AVR microprocessor

Summary: A number of the device creation projects detailed on this website use the Atmel AVR microprocessor as the CPU or the 'brains' behind the device. However, before one can build any of these devices, one has to be able to get the firmware code on the AVR itself. There are a number of ways to achieve this and the method described here is probably not the most efficient way, but it does tend to be one of the less expensive ways of firmware loading and can also put to work some old equipment which you might have lying around earmarked for the trash heap.

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