Calix[n]arenes (n = 4, 5, 6, 8) are "chalicelike" phenol-based macrocycles that are among the most fascinating and highly studied scaffolds in supramolecular chemistry. This stems from the functional and tunable diversity at both their upper and lower rims, their preorganized nonpolar cavities and preorganized ionbinding sites, and their well-defined conformations. Conjugation of calixarene scaffolds with various fluorogenic groups has led to the development of smart fluorescent probes that have been utilized as molecular sensors, in bioimaging, for drug and gene delivery, in self-assembly/aggregation, and as smart materials. The fine-tuning and incorporation of different ligating sites in the calix[4]arene scaffold have produced numerous molecular sensors for cations, anions, and biomolecules. Moreover, the aqueous solubility of p-sulfonatocalix[4]arenes has engendered their potential use in drug/gene delivery and enzymatic assays. In addition, because of their strong optical properties, fluorescent calix[4]arenes have been used to develop smart materials, including gels as well as nonlinear optical, organic light-emitting diode, and multiphoton materials. Finally, significant developments in the utility of fluorescent higher calixarenes have been made for bioapplications. This review critically summarizes the recent advances made in all of these different areas.

Hypoxia is a state of low oxygen tension found in numerous solid tumours.

A major challenge in photodynamic cancer therapy (PDT) is avoiding PDT-induced hypoxia, which can lead to cancer recurrence and progression through activation of various angiogenic factors and significantly reduce treatment outcomes. Reported here is an acetazolamide (AZ)-conjugated BODIPY photosensitizer (AZ-BPS) designed to mitigate the effects of PDT-based hypoxia by combining the benefits of anti-angiogenesis therapy with PDT. AZ-BPS showed specific affinity to aggressive cancer cells (MDA-MB-231 cells) that overexpress carbonic anhydrase IX (CAIX). It displayed enhanced photocytotoxicity compared to a reference compound, BPS, which is an analogous PDT agent that lacks an acetazolamide unit. AZ-BPS also displayed an enhanced in vivo efficacy in a xenograft mouse tumor regrowth model relative to BPS, an effect attributed to inhibition of tumor angiogenesis by both PDT-induced ROS generation and CAIX knockdown. AZ-BPS was evaluated successfully in clinical samples collected from breast cancer patients. We thus believe that the combined approach described here represents an attractive therapeutic approach to targeting CAIX-overexpressing tumors.

A naphthalimide appended rhodamine based fluorescent chemosensor '1' is synthesized which undergoes through bond energy transfer in the presence of Hg(2+) ions in mixed aqueous media.

New triphenylene derivatives 3 and 5, synthesized using a Suzuki-Miyaura coupling protocol and by a click reaction respectively, serve as potent chemosensors for various electron deficient nitroaromatic explosives, such as picric acid, trinitrotoluene, dinitrotoluene and dinitrobenzene. Derivative 5 exhibits a more sensitive response towards the nitroaromatics compared to derivative 3 due to its ordered organization. Furthermore, the solution coated strips of derivative 3 and gel coated strips of derivative 5 can detect picric acid in the range of 14 pg cm(-2), thus providing a simple and low cost method for the detection of picric acid in aqueous solution and in a contact mode.

Simultaneous monitoring and treatment of wound infection is of great importance in the biomedical field. The present work describes the development of a theranostic wound dressing (TH-WD) that can monitor and inhibit wound infection simultaneously. The main component of TH-WD is a polyurethane (PU) scaffold loaded with a ciprofloxacin-based prodrug (Pro-Cip) and a chromogenic probe (H-Cy). In vitro studies demonstrated that TH-WD displayed efficient inactivation (100 ± 4% reduction) of Pseudomonas aeruginosa (ATCC 27853) within 4 h of contact while providing a visual detection of wound infection via a simple color change from yellow to green to red. These results are attributed to the activation of H-Cy and Pro-Cip via hydrolysis of their ester linkages catalyzed by lipase, an extracellular enzyme secreted by bacteria. Moreover, TH-WD is highly selective as it only changes color and releases the active drug (ciprofloxacin) in the presence of certain lipase-secreting pathogenic bacteria such as P. aeruginosa ATCC 27853, and no color change and cytotoxicity were observed when TH-WD was incubated with no- or low-lipase-producing bacteria (e.g., E. coli TOP 10) or skin cell fibroblast. This hence can minimize the emergence of bacterial resistance associated with the overuse of antibiotics and avoid unnecessary cytotoxicity to skin cells. The present system not only provides a visible and noninvasive method to monitor the wound status but also allows the timely administration of antibacterial agents to inactivate bacteria in the wound.

Triphenylene-based discotic liquid crystal 3 bearing 1,2,3-triazole groups has been synthesized using "click" chemistry. Discotic mesogen 3 has good thermal stability, and incorporation of triazole groups results in stabilization of columnar mesophases down to room temperature and formation of organogels in cyclohexane and mixed solvents such as hexane and dichloromethane (4:1 v/v). Characterization of the organogel of 3 in cyclohexane revealed a porous network. However, presence of Cd(2+) ions in solution obstructed the self-assembly of this derivative due to preferred interactions between Cd(2+) ions and triphenylene units over π-π interactions among triphenylene groups. Further, strong emission of derivative 3 in its nonaggregated form makes it a promising fluorescence sensory material for nitroaromatic compounds.

All these three modalities showed superiority with less variation among themselves compared with 3D-CRT plans. Clinical investigation is warranted to determine if these treatment approaches will translate into a reduction in radiation therapy-induced toxicities.