Immobilized enzyme reactors for detection systems in high-performance liquid chromatography

Application of immobilized enzyme reactor in on-line high performance liquid chromatography: A review

“…In this way sensitivity of the detection system is considerably enhanced and determination of trace components in complex matrices therefore become possible. However, some drawbacks such as band broadening due to non-specific binding to the enzyme [7] and the influence of the flow rate on the substrate conversion efficiency in the case of specific mass transfer regimen can limit the application of IMERs in HPLC. Infact when microparticulate supports are employed, the system operates under diffusionlimiting conditions because the substrate reaches the catalytic sites more slowly than the rate of enzymatic product formation [8].…”

Sample Preparation for Chromatographic Analysis

“…Many suitable reaction techniques have been published for this purpose [641][642][643][644][645][646][647][648][649][650]. The derivative reaction is performed after the separation of the sample by the column and prior to detection in a continuous reactor.…”

“…Some typical reaction detector configurations are shown in Figure 8.38. For reactions using solid-phase reagents, immobilized enzymes, etc., a packed bed tubular reactor is used [646,647,650,654]. With segmented flow systems, that generally operate at low pressures, peristaltic pumps are commonly used.…”

“…The packed bed reactor is particularly useful for reactions involving solid-phase reagents such as catalysts, immobilized enzymes and metallic reducing agents [641,642,646,647,658]. Since no reagent solutions are added in this case, there are no additional pumps or mixing units required and no dilution or mixing problems associated with postcolumn reagent addition.…”

Εφαρμογές Ακινητοποιημένων Ενζύμων Σε Οπτικές Και Ηλεκτροχημικές Μεθόδους Ανάλυσης

“…Ένας τρόπος αντιμετώπισης του παραπάνω προβλήματος είναι η "επισήμανση" της προσδιοριζόμενης ουσίας πριν ή μετά τη διαβίβαση από τη στήλη διαχωρισμού. Οι αντιδραστήρες ακινητοποιημένου ενζύμου επιτρέπουν μία τέτοια "επισήμανση", με μετατροπή της μη ανιχνεύσιμης προσδιοριζόμενης ένωσης, μέσω μίας ενζυμικής αντίδρασης, σε μία ένωση που μπορεί να δώσει χαρακτηριστικό αναλυτικό σήμα [59,60]. Εφαρμογές του συνδυασμού αντιδραστήρα ακινητοποιημένου ενζύμου-HPLC έχουν γίνει για την ανάλυση στεροειδών, αμινοξέων, ή σακχάρων, χαρακτηριστικά παραδείγματα των οποίων δίδονται στον Πίνακα 2.3.…”