The commonly used detection methods for plant extracts include:

‌High-Performance Liquid Chromatography (HPLC)‌: This method uses a liquid as the mobile phase and a high-pressure delivery system to pump a single solvent or a mixture of solvents of different polarities, buffer solutions, etc., into a column packed with a stationary phase. The components are separated within the column and then detected by a detector, enabling the analysis of the sample. HPLC is widely used in various fields such as chemistry, medicine, industry, agriculture, commodity inspection, and forensic examination‌.

‌Ultraviolet Spectrophotometry (UV)‌: This method utilizes the absorption of radiation in the 10-800 nm spectral region by certain substances for qualitative and quantitative analysis. It is widely used for the determination of organic and inorganic substances and is characterized by high sensitivity, accuracy, selectivity, ease of operation, and fast analysis speed‌.

‌Thin-Layer Chromatography (TLC)‌: This method involves spreading a suitable stationary phase on a glass plate, plastic, or aluminum sheet to form a uniform thin layer. After sample application and development, the Retention factor (Rf) value is compared with that of a suitable reference substance obtained by the same method for drug identification, impurity testing, or content determination. TLC is a rapid and important technique for the separation and qualitative analysis of small amounts of substances‌.

‌Gas Chromatography (GC)‌: This method uses gas as the mobile phase for chromatographic analysis and is suitable for the separation and analysis of volatile substances, such as volatile aroma components in plant extracts‌.

‌Atomic Absorption Spectrometry (AAS)‌: This method is based on the absorption intensity of the outer electrons of ground-state atoms in the gaseous state to ultraviolet and visible light corresponding to the atomic resonance radiation line to quantitatively determine the content of the measured elements. It is mainly used for the analysis of trace elements in samples‌.

These methods have different principles of action and applications. HPLC and UV are commonly used for standard plant extracts, TLC is used for the detection of proportional extracts, GC is used for the detection of volatile liquids or oils, and AAS is used for the detection of heavy metal content in extracts‌.