## 3 Results
### Analytical Method Validation of Tricyclazole Detection  
The analytical performance of the method for detecting tricyclazole was critically evaluated, focusing on the LOQ, linearity, recovery, and matrix effect (Table 3). The LOQ was determined to be 0.01 mg/kg, which is significantly lower than the maximum residue limit (MRL) of 0.7 mg/kg in Korea (Pesticide MRLs in Food, Ministry of Food and Drug Safety). This indicates that the method possesses adequate sensitivity for detecting tricyclazole levels well below the regulatory limit, ensuring compliance with food safety standards. The method demonstrated excellent linearity, as evidenced by a correlation coefficient (\(r^{2}\)) of 0.9996, which indicates a near-perfect linear relationship between concentration and signal response (Figure S3). This strong linearity is essential for ensuring that quantitative results are accurate and reliable across the scope of concentrations tested.  
Recovery experiments were conducted at three fortification levels: 0.01, 0.1, and 2 mg/kg (Table 3). The recovery rates at these concentrations were consistently excellent, recorded at 95.2%, 95.6%, and 94.7%, respectively. The RSDs were notably low, at 7.9%, 2.8%, and 2.6%, demonstrating the method's precision and reproducibility. Such recovery results provide confidence in the method's robustness and its ability to yield reliable data. Interestingly, the matrix effect (ME) was calculated to be \(-3.1\%\), indicating a slight suppression in signal due to matrix components. This suppression is minor and within acceptable limits [19; 29], suggesting that the method is relatively free from matrix-induced interferences that could potentially bias the results. It was confirmed that no signal was detected in the chromatogram of control sample at the retention time (Figure 2a), and both the solvent standard and the matrix-matched standard at the same LOQ level showed the same intensity (Figure 2b,c), indicating no influence from the rice matrices.  
In previous studies, the matrix effects observed for multiresidue pesticide analysis in rice were significantly higher. For example, using LC-MS/MS, the matrix effects ranged from \(-74\%\) to \(-32\%\) (medium-strong suppression), and in the case of GC-MS/MS, the matrix effects were reported to exceed 500% (strong enhancement) [14; 16; 18]. Such substantial matrix effects can complicate the quantification and detection of pesticide residues, leading to potential inaccuracies in the results. For the precise monitoring of a single active ingredient in agricultural fields, single-residue analysis can offer greater specificity and reduced matrix interference, thus providing more accurate and reliable results.  
\begin{table}
\begin{tabular}{c c c c c} \hline \multirow{2}{*}{\
\begin{tabular}{c} **LOQ** \\ **(mg/kg)** \\ \end{tabular} } & \multirow{2}{*}{**Linearity (\(r^{2}\))**} & \multicolumn{2}{c}{**Recovery (RSD) (\%)**} & \multirow{2}{*}{
\begin{tabular}{c} **ME** \\ **(\%)** \\ \end{tabular} } \\ \cline{3-3}  & & **0.01 mg/kg** & & **0.1 mg/kg** & **2 mg/kg** \\ \hline
0.01 & 0.9996 & 95.2 (7.9) & 95.6 (2.8) & 94.7 (2.6) & \(-3.1\) \\ \hline \end{tabular}
\end{table}
Table 3: Analytical method validation parameters for tricyclazole detection: limit of quantitation (LOQ), linearity, recovery, and matrix effect (ME).