High performance liquid chromatography (HPLC) is one of many test devices used in laboratories. The apparatus is based on classical chromatography, using gas chromatography theory, and technically converts the traditional mobile phase to high-pressure delivery. This article will explain the failure causes and treatment methods of high-performance liquid chromatography (HPLC), as well as its properties, working principle, applications.

How Does High Performance Liquid Chromatography Work?

The mobile phase enters the system by a high-pressure pump, the sample solution enters the mobile phase via a syringe, and the mobile phase is loaded into the chromatographic column (stationary phase) in HPLC chromatography. However, the moving speed of each component after repeated adsorption-desorption distribution in the two-phase sample solution is significantly varied due to the variable distribution coefficients of each component in the two-phase sample solution. It is broken down into a single component that exits the column. As the sample concentration passes through the detector, it is turned into an electrical signal that is supplied to the recorder, and the data is recorded as a graph.

Applications of High Performance Liquid Chromatography

High-performance liquid chromatography (HPLC) is an instrument that uses the principle of high-performance liquid chromatography to examine organic molecules that have high boiling temperatures, are non-volatile, are thermally unstable, and have large molecular weights. It is made up of the liquid storage tank, the pump, the injector, the chromatographic column, the detector, the recorder, and other components. Life sciences, food sciences, pharmaceutical research, and environmental research all make extensive use of HPLC.

1.It can be used to analyze cyclic aromatic hydrocarbons (PAHs), pesticide residues, and other environmental contaminants.

2.It may be used for food nutrition analysis, food additive analysis, food contaminant analysis, and so on.

3.Purification, separation, and determination of molecular weight compounds can be examined at the molecular level in life science, genetic engineering, clinical chemistry, molecular biology, and biochemistry.

4.Application in the medical examination: metabolite analysis and determination in body fluids, pharmacokinetics, clinical medication monitoring, and so forth.

5.Inorganic analysis: examination of anions and cations, for example.

Common Faults and Treatment Methods of High Performance Liquid Chromatography

Fault 1: There are bubbles in the mobile phase; turn off the pump, open the exhaust valve, press the cleaning button, and open the vent; the bubbles continue to emerge from the filter and enter the mobile phase, regardless of how many times the cleaning button is turned on; it cannot be cleared continuously. produced air bubbles.

The cause and how to deal with it: The filter has been drenched in water for an extended period of time, and as a result of mold growth and spread in the filter head, the filter has become clogged by the production of bacteria.The buffer has a tough time passing smoothly through the filter head, and the air flows through the filter under pump pressure and enters the mobile phase.

The filter head was immersed in 5% nitric acid solution for 15 minutes before being ultrasonically cleaned. The filter head can also be soaked in 5% nitric acid solution for 12 hours, shaken gently for 36 hours, rinsed several times with pure water, open the exhaust valve, open the purification key, and remove the gas from the filter tank; if there is still gas in the filter bubbles, soak the filter in 5% nitric acid solution for another 12 hours.

If no bubbles continue to occur in the filter, it implies that the mold in the filter can be killed by nitric acid, and the mobile phase may pass smoothly through the filter. Open the exhaust valve, adjust the pump flow to 1.0 30 mL/min, and rinse 1 The filtrate can be cleaned after about an hour. Close the pressure-reducing valve and flush for 30 minutes with pure methanol.

Fault 2: excessive column pressure

The reason behind this and how to deal with it:

(1) In the column, buffer salts such as ammonium acetate, etc. are deposited;

(2) Deposition of sample contamination

Fault 3: There is no indication of pressure or liquid flow.

The reason behind this and how to deal with it:

The pump sealing gasket has worn; a substantial volume of gas has entered the pump body: handle the first situation by replacing the sealing gasket.

In the second situation, utilize a 50 mL glass syringe at the pump output without assisting in air extraction while the pump is turned on.

Fault 4: The pressure varies dramatically and the flow is unsteady.

The reason for the failure and the technique of treatment: There is a foreign body between the gem ball and the air seat or one-way valve, preventing the two from being sealed together.

Pay attention to the amount of mobile phase produced while working, ensure that the stainless steel filter sinks to the bottom of the liquid storage bottle, avoid inhaling air, and deflate completely when moving. If there is foreign matter between the check valve and the valve seat, for example, remove the check valve and replace it. Ultrasonically clean it in an acetone-filled beaker.

The information presented above is a DRAWELL overview of the high-performance liquid chromatography (HPLC) principle, application, characteristics, failure reasons, and treatment procedures. I hope you found this essay useful.

Many issues can arise when using high-performance liquid chromatography. If the operator understands the root reason of the failure, it can be avoided and eradicated, and the instrument can be used to its full potential.

Of course, if you're wondering where to acquire an excellent HPLC, I recommend DRAWELL's HPLC. As China's leading provider of high-performance liquid chromatography, DRAWELL offers superior HPLC detection capabilities as well as a very competitive HPLC price advantage, making DRAWELL's chromatography the first option for many laboratories worldwide.