ALAT / ALT / GPT Reagents — Clinical Chemistry / Semi-Automated Systems

🔬 1. IFCC Kinetic Method (Standard ALT Method)

Primary Reaction

ALT catalyzes:

L-Alanine + α-Ketoglutarate
→ Pyruvate + L-Glutamate

Indicator (Coupled) Reaction

Pyruvate + NADH + H⁺
→ Lactate + NAD⁺
(catalyzed by LDH)

As ALT activity increases, NADH decreases, and absorbance at 340 nm falls.

Measurement

• Wavelength: 340 nm

• Method: Kinetic, ΔA/min

• Rate proportional to ALT activity (U/L)