HPLC happens to be the most common approach for analyzing the components of amino acids. However, there are quite a number of methods for analyzing amino acids, which you can always use and they include but are not limited to the following:
The use of UV detection of amino acids entails the absorption of the carboxyl group in the range of 200 and 210 nm. Generally, some amino acids are very difficult to analyze as-is unless you have sufficient selectivity and sensitivity. Eventually, the use of derivatization methods are resorted to, and many of these have been used in the past.
This method involves the derivatization of the amino acids before they are used, and then the reaction products are separated before detection. Some of the advantages of using this method include:
- Enables for increasing sensitivity through the use of expensive reagents, which are known to yield lower background levels.
- The rate of reagent consumption can be minimized
- The unreacted derivatizing reagents, if detected, will not cause any problem in the separation column.
The method also comes with certain disadvantages, which include: the sample matrix usually impacts the efficiency of the reaction and the reaction products are sometimes unstable and this could cause errors in the quantization results.
Post Column reaction detection method
Some steps, such as derivatizing reagent delivery and mix, and amino acid separation methods, are used in this method. The steps are allowed to react with amino acids before the products are sending to the detector. This method can be automated to give excellent quantitative reproducibility and performance. Additionally, since the sample components are separated before the reaction, the efficiency of the reaction is less prone to sample matrix and this makes it possible to be used for a wide range of samples.