Cataluminescence-based sensors: principle, instrument and application

Real-time pharmacokinetics via online analysis of exhaled breath

The advantages that on-line breath analysis has shown in different fields have already made it stand as an interesting tool for pharmacokinetic studies. This review summarizes recent progress in the field, diving into the different analytical methods and the different advantages and hurdles encountered. We conclude that there is a wealth of limitations in the application of this technique, and key aspects like standardization are still outstanding. Nevertheless, this is an experimental field that has not yet been fully explored; and the advantages it offers for animal welfare, decrease in the amount of drug needed in experimental studies, and complementary insights to current pharmacological studies, warrant further exploration. Further studies are needed to overcome current limitations and incorporate this technique into the toolbox of pharmacological studies, both at an industrial and academic level.

Cataluminescence Coupled with Photoassisted Technology: A Highly Efficient Metal-Free Gas Sensor for Carbon Monoxide

With the development of green chemistry, metal-free nanocatalysts have gradually substituted metal-based materials, causing widespread concern among researchers in many fields, especially in cataluminescence sensing, because of their long-term stability and environmental friendliness as well as low costs. Besides the catalysts, innovations of assistant technologies for cataluminescence are needed to enhance the oxidation reactivity of the gas molecules or catalytic efficiency of sensing materials. Although, there are some groups enhancing the cataluminescence reaction via various assistant technologies, the development of assistant technologies in cataluminescence sensors is still in its infancy; the design, effect mechanism, and application are still stimulating challenges. Herein, with photodynamic assistant, fluorinated nanoscale hexagonal boron nitride is first employed as a metal-free catalyst to establish a novel cataluminescence method for detecting CO gases, and the cataluminescence reaction mechanism of CO is also investigated in detail. Under the best conditions, the detection limit (3σ) of the CO concentration is 0.005 μg mL^-1, which has been largely improved in cataluminescence methods. The realization of detection of CO from theory to practice through the method of cataluminescence is beneficial for the practical application of metal-free catalysts to detect CO rather than staying at the possibility to detect CO by means of theoretical calculation only.

UV-Assisted Cataluminescent Sensor for Carbon Monoxide Based on Oxygen-Functionalized g-C3N4 Nanomaterials

Cataluminescence (CTL) is one of the most important sensing-transduction principles for the real-time monitoring of atmospheric pollutants. Highly sensitive CTL-based CO detection still remains a challenge because of the relatively poor reactivity of CO and the low catalytic efficiency of the catalysts. Herein, combining ultraviolet (UV)-light activation and chemical modification of the sensing element, we have successfully established a UV-assisted CTL sensor for gaseous CO based on g-C₃N₄ with high sensitivity, selectivity, and stability. UV irradiation can efficiently activate CO molecules and induce the generation of reactive oxygen species (ROS) for CO oxidation. Furthermore, carboxyl groups greatly facilitate the chemisorption of CO on functionalized g-C₃N₄ nanomaterials, thus enhancing the CTL sensitivity. The influences of experimental conditions and the possible catalytic mechanism of CO on functionalized g-C₃N₄ have been investigated in detail. Under the optimal experimental conditions, the proposed CTL sensor presents a detection limit (3σ) toward CO of 0.008 μg mL^-1, which is much lower than the maximum allowable emission concentration of CO in atmospheric conditions (0.030 μg mL^-1). The UV-CTL system is green, sensitive, stable, and low cost, and thus it possesses great potential application in gas sensing.

Artemisinin-Luminol Chemiluminescence for Forensic Bloodstain Detection Using a Smart Phone as a Detector

Forensic luminol chemiluminescence test is one of the most sensitive and popular methods for the determination of latent bloodstains. It mainly uses hydrogen peroxide or sodium perborate as coreactants. The easy decomposition of hydrogen peroxide and sodium perborate in the presence of many ions significantly affects the selectivity. Artemisinin is a natural peroxide that is quite stable in the presence of common ions. In the present study, artemisinin has been exploited for the forensic bloodstain chemiluminescence detection for the first time. Using smart phone as cost-effective portable detector, the visual detection of bloodstains has been achieved with a dilution factor of blood up to 100 000. Moreover, this system shows excellent selectivity against many common species. It can well differentiate bloodstains from other stains, such as coffee, brown sugar, and black tea. Both favorable sensitivity and selectivity makes the present method promising in forensic detection.

Recent advances in cataluminescence-based optical sensing systems

Recent advances in the development of cataluminescence focused on oxygen, temperature, catalyst and instrumentation are summarized.