1‐Hydroxypyrene (1‐HP), which is a biomarker of polycyclic aromatic hydrocarbons (PAHs) carcinogens and represents the internal dose of PAHs exposure in the human body, is detected by a newly designed luminescent Eu‐functionalized metal‐organic framework (1a) sensor. The luminescence of 1a can be effectively quenched by 1‐HP via a fluorescent resonant energy transfer process, thus achieving its recognition of 1‐HP. This is the first use of lanthanide metal‐organic frameworks (Ln‐MOFs) as chemical sensors for 1‐HP. The probe exhibits outstanding performances for sensing 1‐HP, such as high selectivity, excellent sensitivity, fast response, and good reusability. Importantly, the sensing system enables the detection of 1‐HP in real human urine specimens, and a portable 1‐HP urine test paper is also developed. Hence, the reported 1‐HP sensing platform has promising application potential for clinical diagnosis of the intoxication level of PAHs.

A highly selective and sensitive fluorescent sensor for Cd(2+) in aqueous solution based on a lanthanide post-functionalized metal-organic framework was developed.

Unsafe food is a huge threat to human health and the economy, and detecting food spoilage early is an ongoing and imperative need. Herein, a simple and effective strategy combining a fluorescence sensor and one-to-two logic operation is designed for monitoring biogenic amines, indicators of food spoilage. Sensors (methyl red@lanthanide metal-organic frameworks (MR@EuMOFs)) are created by covalently modifying MR into NH -rich EuMOFs, which have a high quantum yield (48%). A double-stimuli-responsive fluorescence center is produced via energy transfer from the ligands to Eu and MR. Portable sensory hydrogels are obtained by dispersing and solidifying MR@EuMOFs in water-phase sodium salt of carboxy methyl cellulose (CMC-Na). The hydrogels exhibit a color transition upon "smelling" histamine (HI) vapor. This transition and shift in the MR-based emission peak are closely related to the HI concentration. Using the HI concentration as the input signal and the two fluorescence emissions as output signals, an advanced analytical device based on a one-to-two logic gate is constructed. The four output combinations, NOT (0, 1), YES (1, 0), PASS 1 (1, 1), and PASS 0 (0, 0), allow the direct analysis of HI levels, which can be used for real-time food-freshness evaluation. The novel strategy suggested here may be a new application for a molecular logic system in the sensing field.

Four luminescent lanthanide–organic frameworks (Ln = Eu3+, Tb3+, Sm3+ and Dy3+), isostructural to MOF-LIC-1(Gd), are assembled. Multiple colors are obtained for the system and white-light emission is realized by the single component Sm(iii) framework. Most interestingly, Eu-MOF performs highly selective and sensitive luminescence sensing of Al3+.

Metal-organic frameworks (MOFs) are intriguing platforms with multiple functionalities. Additional functionalization of MOFs generates novel materials for various applications. Here, three main topics are examined regarding the functionalization of MOFs for use as photoactive materials. The first is chemical approaches for postsynthetic modification of the metal clusters and organic linkers in MOFs; that is, sites on pore surfaces and chemical trapping of photoactive moieties within the pores, which create materials with chemical functionalities for water splitting and CO reduction by light. The second topic focuses on the functionalization of MOFs for photochemical response and the versatile applications of such materials. State-of-the-art research on functionalizing MOFs through photochemical reactions on the pore surface and within the pores as guests is also summarized. The third topic introduces the functionalization of MOFs for photofunctional materials, including photoluminescent tuning and integration, photoluminescent LED devices and barcodes, and photophysical applications for chemical sensing. Finally, conclusions and perspectives on the fields are given.

A lanthanide-functionalized MOF was developed as a highly selective and sensitive fluorescent probe for hippuric acid (HA) in urine, which is the main metabolite of inhaled toluene in the human body and is considered a biological indicator of toluene exposure.

A Eu(3+) post-functionalized metal-organic framework of nanosized Ga(OH)bpydc(Eu(3+)@Ga(OH)bpydc, 1a) with intense luminescence is synthesized and characterized. Luminescence measurements reveal that 1a can detect ammonia gas selectively and sensitively among various indoor air pollutants. 1a can simultaneously determine a biological ammonia metabolite (urinary urea) in the human body, which is a rare example of a luminescent sensor that can monitor pollutants in the environment and also detect their biological markers. Furthermore, 1a exhibits appealing features including high selectivity and sensitivity, fast response, simple and quick regeneration, and excellent recyclability.

A new class of lanthanide luminescent MOFs was generated by postsynthetic modification encapsulating Eu3+ into the pores of MIL-121 (Eu3+@MIL-121). More significantly, the robust Eu3+@MIL-121 shows fast response and high sensitivity to Ag+ ions in aqueous solution, due to a great enhancement in the Eu-luminescence.