FSTest Chlorpyrifos Rapid Test Kit (10 Tests)

Product Overview

The FSTest Chlorpyrifos Rapid Test Kit (Colloidal Gold) is a professional-grade, rapid screening tool engineered for the qualitative detection of chlorpyrifos residues in fresh fruits and vegetables. Chlorpyrifos is a widely utilized organophosphorus insecticide. Strict residue tracking is essential for agricultural producers, international food exporters, and laboratory auditors aiming to maintain compliance with strict global food safety regulations and Maximum Residue Limits (MRLs).

By bypassing the need for complex, time-consuming laboratory infrastructure (such as HPLC or GC-MS), this field-ready kit compresses agricultural sample extraction into a simplified, room-temperature workflow. It serves as an indispensable first-line defense in fresh produce supply chains and corporate food safety compliance monitoring programs.

Product Highlights & Key Benefits

· Fast Field Turnaround: Complete the entire assay workflow and achieve highly reliable visual result readouts within just 8 to 10 minutes post-preparation.

· Highly Customizable Limits of Detection: Uniquely calibrated to adapt across different fruit and vegetable matrices. By adjusting the sample supernatant dilution ratios, the kit dynamically targets a wide array of regulatory cut-off thresholds ranging from 0.02 mg/kg up to 2 mg/kg.

· Fully Self-Contained Kit Architecture: Arrives fully packed with all necessary consumables—including 10 test cassettes, 10 microwells, 20 centrifuge tubes (2 mL), 1 bottle of extracting solution (50 mL), and 2 sampling bottles (30 mL).

· Definite Visual Interpretation: Utilizes a lateral flow immunochromatographic format where an increasing insecticide concentration causes the Test (T) line to fade or completely disappear, removing subjective reading errors.

· High Specificity & Zero Cross-Reactivity: Rigorously validated to show zero cross-reactivity with other high-profile agricultural chemicals. Samples containing 1 mg/L of phorate, paclobutrazol, carbendazim, and paraquat consistently return negative results.

· Exceptional Shelf Preservation: Unopened test kits can be safely kept in a sealed, cool, and dry location between 4–30°C for an extended shelf-life of up to 18 months.

Technical Principle: Lateral Flow Immunochromatography

The test is based on a competitive lateral flow immunochromatographic assay format. The test cassette houses a pre-coated reaction membrane containing a Control (C) zone and an invisible Test (T) zone before fluidics activation.

Extracted Insecticide Residues + Antibody-Conjugates → Lateral Flow → Inhibition of Binding at T-Zone → Faded or Absent T-Line

When the treated sample solution is applied into the sample well, the liquid migrates laterally across the strip via capillary action and reacts with pre-coated recombinant antigens. The color intensity of the T line has an opposite correspondence with the chlorpyrifos concentration in the sample. If the pesticide residue meets or exceeds the target detection threshold, it binds to the antibodies and completely inhibits them from anchoring onto the antigens at the T zone, 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 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 g of the cut sample pieces into a 30 mL sampling bottle and mix with 3 mL of extracting solution.

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

·  Final Matrix Dilution: Follow either the Standard Protocol or Two-Step Protocol configurations detailed in the matrix tables above based on the produce type being verified.

2. Running the Assay

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

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

· Transfer all of the mixed liquid from the microwell directly into the round sample well on the test cassette.

· Interpret the visual results between 8 to 10 minutes. Results are invalid after 10 minutes.

Results Determination & Action Guide

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

· Positive (+): The Control (C) line develops normally, but the Test (T) line is visibly lighter or fails to appear completely. This indicates that insecticide residues meet or exceed the designated threshold 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, Extracting solution (50 mL) x 1, 30 mL sampling bottles x 2, 2 mL centrifuge tubes x 20, User manual).

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

· Shelf Life:18 months under proper sealed storage parameters.