Table 6.
Comparison between the presented method and the reported spectrofluorometric methods for MSG analysis
| Derivatizing reagent | Solvent | Time | Wavelength λex/ λem (nm) | Linearity range (µg/mL) | Sample | Comments | Ref |
|---|---|---|---|---|---|---|---|
| NAD+, GDH | Glycine hydrazine buffer | 30 min | 340/450 | 1.69 × 10–5 ‒50.7 × 10–5 | Biological sample |
• Reagents must be freshly prepared and stored properly to ensure short term stability • Reactions involve more than one step • Expensive enzymes and substrates are needed |
[49] |
| Thionine, NAD+, GDH | Phosphate buffer pH 7 ± 0.1 | 20 min | 590/620 | 0‒135.28 | Food & blood samples | [24] | |
| Fluorescamine | Phosphate buffer pH 9, acetone | – | 393* | 0.1‒1 | Commercial dried soap | • Acetone is used as solvent for reagent | [25] |
| Dansyl hydrazine attached to dextran | 1% Phosphate buffer | …. | 275/475 | 16.9‒4227 | Biological sample |
• Several reagents are used for preparation of DD so time is consuming • Decomposition of DD may be occurred |
[26] |
| Iron (III) salicylate | Water | – | 290/411 | 4.22‒42.27 | Instant noodles |
• Simple, rapid, and instantaneous reaction • Water is used as a solvent |
This method |
GDH l-Glutamate dehydrogenase, NAD+ Nicotinamide adenine dinucleotide
*Synchronous derivative spectrofluorometry