## 1 Introduction  
As national development demands have grown, the production and usage of explosives have increased annually, finding widespread applications in sectors such as mining [1], demolition of buildings [2], scientific experiments [3], mountain and road construction [4], oil extraction [5], explosive processing [6], controlled blasting [7], satellite launches, and aerospace projects [8, 9]. Over a considerable period, the most commonly used explosives globally have included dinitrotoluene (DNT), trinitrotoluene (TNT), RDX, HMX (cyclotetramethylene tetranitramine), and CL-20 (hexanitrohexaazaisowurtzitane). However, the high sensitivity inherent to these explosives poses significant risks during storage and transport, leading to potentially unpredictable hazards [10, 11, 12, 13, 14]. Consequently, attention has shifted towards insensitive energetic materials like 2,2\({}^{\prime}\),A\({}^{\prime}\),6,6\({}^{\prime}\)-hexanitrostilbene (HNS). In comparison to other high explosives, HNS not only produces high energy but also possesses excellent impact resistance and thermal stability [15], facilitating its extensive application in fields such as oil extraction, aerospace, and space technology [16]. However, during the production and use of HNS, the generation of explosive wastewater is inevitable. This wastewater contains highly toxic and mutagenic nitroaromatic compounds (NACs), and if released untreated, can severely contaminate soil and water systems, posing significant risks to both flora and fauna, as well as human health [17; 18; 19]. Direct contact with nitroaromatic compounds can even lead to the onset of cancer in humans [20]. Moreover, the detonation of explosives releases toxic chemicals and disperses large fragments of unexploded ordnance into the environment, leading to the contamination of local soil, sediment, and both surface and groundwater with explosive residues that can persist for decades [21; 22]. To mitigate these risks, employing high-performance liquid chromatography and mass spectrometry for the qualitative and quantitative analysis of HNS and its degradation products is essential. However, research on the detection of HNS and its degradation products has been limited, focusing primarily on two methodologies: gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-mass spectrometry (LC-MS) [23]. GC-MS is an analytical method that first utilizes gas chromatography to separate compounds in complex samples, followed by mass spectrometry to identify them. The specific process includes sample vaporization, chromatographic separation, electron impact ionization, mass-to-charge ratio separation, ion detection, and data analysis. Previous GC-MS methods for HNS detection often involved cumbersome sample preparation steps. These steps included extraction, drying under nitrogen flow, and dissolving the residue in dichloromethane, as well as long detection times, sometimes requiring up to 80 min [18]. In contrast, LC-MS simplifies sample preparation, requires smaller sample volumes, and avoids the need for high-temperature (280 \({}^{\circ}\)C) vaporization, making it more suitable for HNS detection. LC-MS [24] is an analytical method that employs liquid chromatography to separate compounds in complex liquid samples, followed by mass spectrometry for compound identification. This process includes sample introduction, chromatographic separation, compound ionization, mass spectrometric analysis, ion detection, and data analysis. Recently, [PERSON] et al. [25] utilized high-performance liquid chromatography (HPLC) for the quantitative validation of HNS, detecting HNS concentrations in the range of 2.00-20.00 mg/L. [PERSON] et al. [26] used a Merck-Hitachi L-6200 HPLC (Labscan Ltd., Dublin, Ireland) with standard HNS solutions diluted in acetonitrile, detecting HNS concentrations ranging from 0.04 to 0.64 mg/L.