Electronic Effect Driven Specific and Sensitive Recognition toward GHB

Precise detection of a trace substance that intrinsically possesses weak chemical activity and less-distinctive spatial structure is of great significance, but full of challenges, as it could not be effectively recognized via either an active covalent reaction process or multiple noncovalent interactions toward its simple structure. Here, the electronic-effect-driven recognition strategy was proposed to visually sense an illicit drug, γ-hydroxybutyric acid (GHB), which was treated as an analyte model due to its inherent simple structure. In particular, a sensing system composed of two probes substituted by the nitro (-NO2) and the hydrogen (-H), was constructed with the characteristic yellow coloring and blue fluorescence, as well as high sensitivity (0.586 ng/mL), fast response (0.2 s), and specific recognition, even in the presence of 22 interferents. In addition, a portable eyeshadow box-like sensing chip was fabricated and proven to be reliable and feasible in sensing GHB disguised in liquors for self-protection in a covert manner. Hence, this work developed an electronic-effect-driven modulation strategy of the recognition interaction between the probe and the analyte and, thus, would open up a new thought for detecting the analyte with weak activity and a simple structure, as well as propel the relevant application in real scenarios.

In situ, real-time, colorimetric detection of γ-hydroxybutyric acid (GHB) using self-protection products coated with chemical receptor-embedded hydrogel

Due to the increase in drug-facilitated sexual assault (DFSA) enabled by the illegal use of drugs, there have been constant demands for simple methods that can be used to protect oneself against crime in real life. γ-Hydroxybutyric acid (GHB), a central nervous system depressant, is one of the most dangerous drugs for use in DFSA because it is colorless and has slow physiological effects, which pose challenges for developing in situ, real-time GHB monitoring techniques. In this study, we developed a method for in situ colorimetric GHB detection using various self-protection products (SPPs) coated with 2-(3-bromo-4-hydroxystyryl)-3-ethylbenzothiazol-3-ium iodide (BHEI) as a chemical receptor embedded in hydrogels. Additionally, smartphone-based detection offers enhanced colorimetric sensitivity compared to that of the naked eye. The developed SPPs will help address drug-facilitated social problems.

Heteroditopic chemosensor to detect γ-hydroxybutyric acid (GHB) in soft drinks and alcoholic beverages

Drug-Facilitated Sexual Assault (DFSA) is a problem of considerable dimensions on a global scale. Among the different compounds used in DFSA assaults, 4-hydroxybutyric acid (GHB) is one of the most elusive due to its physical and biological characteristics. Therefore, the development of real-time detection methods to detect GHB not only in drinks but also in urine is very important for personal and social security. Here, we report two new heteroditopic chemosensors capable of recognizing and detecting GHB in soft drinks, alcoholic beverages and synthetic urine. The compounds have two moieties: a trifluoroacetyl group and a thiourea, which are able to interact respectively with the hydroxyl and the carboxylic groups present in the GHB structure. In addition, the distance between these two groups has been optimized to allow a double interaction which guarantees the recognition even in very competitive media such as beverages or urine samples.