Capillary electrophoresis coupled to contactless conductivity detection for analysis of amino acids of agricultural interest in composting

Abstract

Composting is a sustainable approach to manage animal and vegetal waste generated in the Fundação Parque Zoológico de São Paulo. The resulting compost is often used in ZOO's premises as an organic fertilizer for the production of vegetables, which is further used to feed the animals. The composting product provides many forms of mineral and also amino acids (AA) that are absorbed by plants as nutrients. Since most amino acids absorb only slightly or not at all in the UV wavelengths, we developed a method for the determination of AA of agricultural interest in the composting samples. Due to the complexity of samples, we used ion exchange chromatography for the purification of AA prior to analysis. The proposed CZE-C D method allowed a separation of the AA in a short analysis time (less than 3.0 min), with great linearity (with R ranging from 0.993 to 0.998). Using a BGE of 10 mmol/L TEA, reduction of high-frequency noise and lower baseline fluctuations were obtained. The LOQ for the five AA were around 35 μmol/L, and were adequate for our purpose. In addition, the method showed good precision (RSD of peak area and migration time less than 1.55 and 1.16%, respectively).

Recent developments in capillary and microchip electroseparations of peptides (2015–mid 2017)

“…CE methods are employed also for peptide/protein characterization by their AA composition and AA sequence. CE and CE‐MS applications for AA analysis, including AA analysis of complete peptide hydrolysate and separations of AA enantiomers are summarized in several reviews . AA sequences of CE separated peptides are usually obtained by their tandem MS detection .…”

Recent advances in amino acid analysis by capillary electromigration methods: June 2015–May 2017

“…According to a sustainable policy, composting animal and/or vegetal waste is of interest. As produced organic fertilizer is recycled to allow plants to feed animals, its AA contents were analysed in Brazil . Due to the complexity of the biological and mineral matrix, anion exchange chromatography was performed before AA analysis.…”

Contactless conductivity detection for analytical techniques: Developments from 2016 to 2018

“…Inorganic anions/cations were determined in mineral fertilizers using dual‐channel CE‐C 4 D system with short capillaries and a semi‐automated set‐up for liquid delivery . CE‐C 4 D was also used for monitoring of amino acids content during composting of animal and vegetal waste .…”