FSTest Difenoconazole Rapid Test Kit (10 Tests)

Product Overview

The FSTest Difenoconazole Rapid Test Kit (Colloidal Gold) is a professional-grade, rapid screening tool engineered for the qualitative detection of difenoconazole residues in fresh fruits and vegetables. Difenoconazole is a widely monitored broad-spectrum triazole fungicide critical to global agricultural pest management and modern crop protection. Ensuring strict residue tracking is vital for agricultural growers, fresh food supply chain operators, and export compliance auditors striving to conform with international food safety standards and Maximum Residue Limits (MRLs).

By eliminating the immediate necessity for complex and costly laboratory infrastructure (such as HPLC or GC-MS), this field-ready assay compresses agricultural chemical extraction into a simplified, room-temperature workflow. It serves as an indispensable first-line defense in fresh produce logistics, crop harvesting hubs, and corporate quality compliance screening programs.

Product Highlights & Key Benefits

· High-Speed Field Turnaround: Complete the entire screening assay workflow and achieve highly reliable visual result readouts within just 5 to 8 minutes post-sample-preparation.

· Dynamic Matrix-Specific Detection Limits: Calibrated to adapt flexibly across diverse food matrices. By adjusting the sample supernatant dilution ratios, the kit precisely targets regulatory cut-off thresholds ranging from an ultra-sensitive 0.02 mg/kg up to 15 mg/kg.

· Massive Fruit & Vegetable Matrix Adaptability: Officially validated for cross-commodity verification, covering over 50 specific agricultural crops including potato, asparagus, sweet potato, pomegranate, watermelon, garlic, cabbage, cauliflower, cucumber, mandarin, orange, plum, mango, papaya, pineapple, zucchini, ginger, broccoli, onion, tomato, loofah, green bean, apple, pear, peach, grape, lychee, eggplant, bell pepper, okra, lemon, pomelo, avocado, snow pea, Hami melon, Chinese cabbage, banana, green onion, leaf lettuce, celery, strawberry, kiwifruit, loquat, blueberry, spinach, watercress, and more.

· Definite Visual Interpretation: Utilizes a competitive lateral flow immunochromatographic assay format where the color intensity of the Test (T) line shares an opposite correspondence with the difenoconazole concentration, eliminating analytical ambiguity.

· High Specificity & Zero Cross-Reactivity: Proven to stay entirely unaffected by non-target agrochemicals. Samples containing up to 10 mg/L of common alternative treatments—including Chlorpyrifos, Chlorothalonil, Carbendazim, and Procymidone—consistently return clear negative results.

· Reliable Ambient Storage & Preservation: Unopened test kits can be safely kept tightly sealed in a cool, dry location between 4–30°C for a full guaranteed shelf-life of up to 12 months. Do not freeze.

Technical Principle: Lateral Flow Immunochromatography

The test strip is based on a competitive inhibition immunochromatography mechanism. The test cassette houses an integrated testing window containing an invisible Test (T) zone and a Control (C) zone before fluidics activation.

Extracted Fungicide Residues + Antibody Reagents -> Lateral Flow -> Competition with Pre-coated Recombinant Antigens -> Faded or Absent T-Line (Inhibitory Response)

When a treated sample solution is dispensed into the sample well of the device, the liquid migrates laterally across the surface of the test strip via capillary action and reacts with pre-coated recombinant antigens. The intensity of color on the T test line has an opposite correspondence with the difenoconazole concentration in the sample. If the pesticide residue meets or exceeds the targeted detection threshold, it alters the binding kinetics, causing the T line to fade visibly or disappear entirely. For a clean, negative sample, a strong, distinct red band forms at the T zone. The Control (C) line must always develop after a sample is applied to confirm the test fluidics are functional and valid.

Specifications & General Parameters

Step-by-Step Procedure

1. Simple Sample Extraction & Preparation

·  Comminution: Cut the fresh fruit or vegetable sample into small pieces (approx. 0.5 cm x 0.5 cm).

·  Primary Extraction: Weigh exactly 2.0g (±0.1g) of representative sample into a sampling bottle and mix with 3 mL of the provided extracting solution.

·  Mixing & Settling: Vortex or shake the bottle thoroughly for 1 minute, then let it stand undisturbed for 1 minute to allow layers to separate. (Note: If the resulting supernatant liquid layer is cloudy or not completely clear, transfer 1 mL of fluid into a centrifuge tube and centrifuge at 4000 rpm for 3 minutes).

·  Matrix Dilution: Execute the specific X & Y dilution protocol as defined in the matrix guide section above based on the commodity being verified.

2. Running the Assay

· Prior to testing, ensure the test cassette and solution have equilibrated to a proper operating temperature environment (20–40 degrees C) and place the device on a flat surface.

· Pipette exactly 100 uL of the prepared final sample solution into a reagent microwell, mix for 3 to 5 times using the pipette fluidics, and let it stand undisturbed for 3 minutes.

· Transfer all of the mixed solution from the microwell directly into the sample well of the test cassette.

· Interpret the visual results between 5 to 8 minutes. (Do not read after 8 minutes, as late chemical shifts render the test invalid).

Results Determination & Action Guide

· Negative (-): Both the Control (C) line and Test (T) line develop a strong, distinct red band. This confirms that difenoconazole fungicide residues are safely below the targeted regulatory cutoff threshold limit.

· Positive (+): The Control (C) line develops normally, but the Test (T) line is visibly lighter or fails to appear completely. This indicates that fungicide residues meet or exceed the designated threshold cutoff limit.

· Invalid: The Control (C) line fails to show any visible color band, regardless of the appearance of the T line. This signals an operational error, an uncalibrated pipette, or a compromised strip. The sample must be re-tested using a brand new cassette.

Storage & Packing Specifications

· Kit Capacity:10 tests per box (Test cassettes x 10, Microwells x 10, Centrifuge tubes (2mL) x 10, Extracting Solution (70mL) x 1, 30mL sampling bottles x 2, User manual).

· Storage Environment:Store tightly sealed in a cool, dry location between 4–30 degrees C. Do not freeze.

· Shelf Life:12 months under proper sealed storage parameters.