Photochemical Derivatives

PHRE-15   Photochemical derivative unit

Applicable to: Chinese medicine aflatoxin detection

Scope of application:

The photochemical derivatizer is widely used in the HPLC detection of aflatoxins and sulfonamides. It can enhance the fluorescence intensity of aflatoxin B1 and G1, and the detection limit of aflatoxin B1 and G1 can reach 0.1 μg/L; Fluorescence intensity of sulfonamides: Sulfadiazine, Sulfapyridine, Sulfamerazine, Sulfamethazine, Sulfamethoxydiazine, Sulfaquinoxaline ), the detection limit reached about 10 μg/L.

When used, the photochemical derivatizer is placed between the chromatographic column and the detector, and the post-column continuous photochemical derivatization reaction is performed to improve the sensitivity and/or response selectivity of the fluorescence, ultraviolet, electrochemical detection and chemiluminescence detectors.

Equipment composition

The photochemical post-column derivatizer includes the following components:

Lamp holder with switch

UV lamp, 254nm (U.V. lamp, 254nm)

knitted reactor coils specially designed for the Reactor holder

PEEK fittings

installation and use

Connect one end of the polytetrafluoroethylene tube on the derivatizer to the outlet end of the chromatographic column and the other end to the inlet end of the fluorescence detector. There is no connection direction requirement.

Chromatographic conditions

Chromatograph;

Fluorescence detector;

    C18 column: 250mm (length) × 4.6mm (diameter), the particle size of the filler is 5μm;

    Mobile phase: 55% methanol;

Flow rate: 1mL/min;

Column temperature: 40℃;

    Excitation wavelength: 360nm;

    Emission wavelength: 450nm;

Note: If the column is different (length, manufacturer or model), the mobile phase can be fine-tuned between 40% and 60%.

Experimental drawings

    Chromatograms of total aflatoxin before and after derivatization

    The contents of various toxins are: B1=10μg/L, B2=3μg/L, G1=10μg/L, G2=3μg/L

Features

— No need to use chemicals (reduces testing costs while avoiding operator exposure to toxic chemicals);

— Adopt imported derived pipelines and UV lamps, with stable quality and long service life;

— The minimum detection limits of aflatoxins B1, B2, G1, and G2 are all less than 0.5ppb;

— Compliant with AOAC 2005.08, AOAC2008.02, AOAC Aa 11-05, China Taiwan Standard (Shi Zi 0981800370 Announcement) and the European Pharmacopoeia 2.8.18 standard analytical method;

— Comply with Chinese national standards and import and export inspection standards

technical parameter

Dimensions (L*W*H): 330*42.5*85mm

Power supply: 220V/50Hz

UV lamp life: about 2000 hours

Power: 8W

Derivative tube material: PTFE (polytetrafluoroethylene) length 15m

Maximum pressure: 500psi (35 kg/cm2)

Weight: about 4kg

Derivative Line ID: 0.0075"

Comparison of applied and non-applied photochemical derivatizers

Figure 1 Chromatograms of aflatoxins B1, B2, G1 and G2 without photochemical derivatization of 26ug/L

Figure 2 Chromatograms of aflatoxins B1, B2, G1 and G2 using photochemical derivatization of 26ug/L