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Ink as an important part of documents is a key material evidence in the field of forensic science. Its in-depth study and accurate identification are of great significance for the detection and trial of cases. Different inks may have different volatile components, so these volatile components play an important role in the identification of ink and the judgment of the writing age. According to the different application fields and components, the types and components of ink are sorted out, and various instrument methods for the identification of volatile components are introduced, mainly including UV-Vis spectroscopy, Raman spectroscopy, infrared spectroscopy, fluorescence spectroscopy, gas chromatography，gas-liquid combination method, mass spectrometry，etc. These methods have their own advantages and disadvantages, and are suitable for different inks. In addition, the development of ink volatile component testing methods is prospected, and the existing defects in the current methods are pointed out, in order to provide reference for forensic science document testing workers. [ABSTRACT FROM AUTHOR]

Two novel stigmasterol derivatives as gelators are synthesized，and named as compounds 1 and 2， respectively. The structure and properties of gels are studied by scanning electron microscopy（SEM），Fourier transform infrared spectroscopy（FT-IR）and UV-Vis spectrophotometer. The results of the gelation properties of compounds 1 and 2 show that they could gelate in DMSO and methanol. Compound 1 also forms a stable gel in DMSO/water mixed solvents at a volume ratio of 9∶1，8∶2，and 7∶3，respectively. In addition，when compounds 1 and 2 are gelated at a mass concentration of 12 mg/mL in DMSO，the gel-sol phase transition temperatures（Tgel）of the two compounds are 51 and 46 ℃，respectively，indicating that the thermal stability of their gelation decreases significantly with the increase of steroidal structural units in the gelator. With the increase of steroid structural units in the gelators，the thermal stability of the gel formation decreases significantly. On this basis，the gel prepared by compound 1 is used as the carrier，and its encapsulation and release in rhodamine B and methylene blue，as well as the anticancer drug doxorubicin are studied by UV-Vis spectroscopy. The results show that the prepared gels could be used as a drug carrier，and the maximum release value reaches 84% in water at 240 min. Furthermore，this study may provide a useful idea for the preparation of stigmasterol derivative gels and its application as a drug carrier in drug delivery. [ABSTRACT FROM AUTHOR]