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Boron neutron capture therapy (BNCT) as a binary targeted particle radiotherapy strategy has shown potent anti‐cancer potential. However, biological barriers and restricted blood supply pose challenges in achieving adequate boron concentration within deep‐seated tumor lesions. BNCT with other anti‐cancer therapies, such as X‐ray radiotherapy and photothermal therapy, is devised to address the limitations of BNCT efficiency. However, the potential risk of organ‐accumulating toxicity and treatment complexity of dual exogenous activation hinders its development. To address this problem, newly redox‐responsive boron nano‐chains (RBNC) are reported that combine BNCT and endogenous chemodynamic therapy (CDT)‐enhanced ferroptosis. RBNC specifically activates nanoparticle size conversion (large‐to‐small) in response to GSH/H2O2 in the tumor microenvironment, releasing boron delivery agents boron quantum dots (BQD) and Fe3+. RBNC exhibits negligible systemic toxicity while demonstrating high boron accumulation at tumor. Meanwhile, the introduction of Fe3+ not only produces ·OH through reaction with H2O2, but also depletes GSH and reduces GPX4 activity in tumors, resulting in amplified intracellular oxidative stress and chemodynamically enhanced ferroptosis. Thus, the work provides a strategy to solve the problem of insufficient boron concentration and poor targeting of boron delivery agents and fill the gaps of BNCT combined with CDT and ferroptosis. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is a binary cancer therapy, which combines the biochemical targeting of a boron‐containing drug with the regional localization of radiation treatment. Although the concept of BNCT has been known for decades, the selective delivery of boron into tumor cells remains challenging. G protein‐coupled receptors that are overexpressed on cancer cells in combination with peptidic ligands can be potentially used as shuttle system for a tumor‐directed boron uptake. In this study, we present the generation of short, boron‐rich peptide conjugates that target the ghrelin receptor. Expression of the ghrelin receptor on various cancer cells makes it a viable target for BNCT. We designed a novel hexapeptide super‐agonist that was modified with different specifically synthesized carborane monoclusters and tested for ghrelin receptor activation. A meta‐carborane building block with a mercaptoacetic acid linker was found to be optimal for peptide modification, owing to its chemical stability and a suitable activation efficacy of the conjugate. The versatility of this carborane for the development of peptidic boron delivery agents was further demonstrated by the generation of highly potent, boron‐loaded conjugates using the backbone of the known ghrelin receptor ligands growth hormone releasing peptide 6 and Ipamorelin. A stable meta‐carborane building block was used to generate potent, boron‐rich peptide agonists that target the ghrelin receptor. Owing to the overexpression of the ghrelin receptor in various tumors, the carborane‐peptide conjugates can be considered as potential boron delivery agents for boron neutron capture therapy. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is a physiologically focused radiation therapy that relies on nuclear capture and fission processes. BNCT is regarded as one of the most promising treatments due to its excellent accuracy, short duration of therapy, and low side effects. The creation of novel boron medicines with high selectivity, ease of delivery, and high boron‐effective load is a current research topic. Herein, boron‐containing carbon dots (BCDs) and their human serum albumin (HSA) complexes (BCDs‐HSA) are designed and synthesized as boron‐containing drugs for BNCT. BCDs (10B: 7.1 wt%) and BCDs‐HSA exhibited excitation‐independent orange fluorescent emission which supported the use of fluorescence imaging for tracking 10B in vivo. The introduction of HSA enabled BCDs‐HSA to exhibit good biocompatibility and increased tumor accumulation. The active and passive targeting abilities of BCDs‐HSA are explored in detail. Subcutaneous RM‐1 tumors and B16‐F10 tumors both significantly decrease with BNCT, which consists of injecting BCDs‐HSA and then irradiating the area with neutrons. In short, this study provides a novel strategy for the delivery of boron and may broaden the perspectives for the design of boron‐containing carbon dots nanomedicine for BNCT. [ABSTRACT FROM AUTHOR]

Metastatic spinal tumors are increasingly prevalent due to advancements in cancer treatment, leading to prolonged survival rates. This rising prevalence highlights the need for developing more effective therapeutic approaches to address this malignancy. Boron neutron capture therapy (BNCT) offers a promising solution by delivering targeted doses to tumors while minimizing damage to normal tissue. In this study, we evaluated the efficacy and safety of BNCT as a potential therapeutic option for spine metastases in mouse models induced by A549 human lung adenocarcinoma cells. The animal models were randomly allocated into three groups: untreated (n = 10), neutron irradiation only (n = 9), and BNCT (n = 10). Each mouse was administered 4‐borono‐L‐phenylalanine (250 mg/kg) intravenously, followed by measurement of boron concentrations 2.5 h later. Overall survival, neurological function of the hindlimb, and any adverse events were assessed post irradiation. The tumor‐to‐normal spinal cord and blood boron concentration ratios were 3.6 and 2.9, respectively, with no significant difference observed between the normal and compressed spinal cord tissues. The BNCT group exhibited significantly prolonged survival rates compared with the other groups (vs. untreated, p = 0.0015; vs. neutron‐only, p = 0.0104, log‐rank test). Furthermore, the BNCT group demonstrated preserved neurological function relative to the other groups (vs. untreated, p = 0.0004; vs. neutron‐only, p = 0.0051, multivariate analysis of variance). No adverse events were observed post irradiation. These findings indicate that BNCT holds promise as a novel treatment modality for metastatic spinal tumors. [ABSTRACT FROM AUTHOR]

Frontispiece: Designed Boron-Rich Polymeric Nanoparticles Based on Nano-ion Pairing for Boron Delivery Keywords: boron neutron capture therapy; boron cluster compounds; nano-ions; polymer nanoparticles; self-assembly EN boron neutron capture therapy boron cluster compounds nano-ions polymer nanoparticles self-assembly 1 1 1 11/16/20 20201111 NES 201111 B Boron-rich nanoparticles b (boron content ca. 15-20 wt%) of designed size and shape were prepared and studied as promising boron-delivery agents in nanomedicine. Boron neutron capture therapy, boron cluster compounds, nano-ions, polymer nanoparticles, self-assembly. [Extracted from the article]

Drug delivery systems (DDSs) are designed to deliver therapeutic agents to specific target sites while minimizing systemic toxicity. Recent developments in drug‐loaded DDSs have demonstrated promising characteristics and paved new pathways for cancer treatment. Light, a prevalent external stimulus, is widely utilized to trigger drug release. However, conventional light sources primarily concentrate on the ultraviolet (UV) and visible light regions, which suffer from limited biological tissue penetration. This limitation hinders applications for deep‐tissue tumor drug release. Given their deep tissue penetration and well‐established application technology, X‐rays have recently received attention for the pursuit of controlled drug release. With precise spatiotemporal and dosage controllability, X‐rays stand as an ideal stimulus for achieving controlled drug release in deep‐tissue cancer therapy. This article explores the recent advancements in using X‐rays for stimulus‐triggered drug release in DDSs and delves into their action mechanisms. [ABSTRACT FROM AUTHOR]

Carboranes and BODIPYs are the well known boron containing compounds. Both are relatively easy to functionalize, and small modification in their structures allow turning of their spectroscopic properties readily suggest the importance of carborane‐BODIPY conjugates. The combination of boron rich carborane and photosensitizers activatable BODIPYs have potentials for adequate boron delivery to the cancer tissues for successful cancer therapy. This review covers the most recent development of carborane‐BODIPY conjugates in space electronic energy transfer, photoinduced electron transfer, fluorescence emission and AIE behaviors, and as promising BNCT agents. Given the high potential and flexibility of this carborane‐BODIPY conjugates, we believe that major developments are to be expected in the field of both material and medicinal science. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is one of the most promising treatments among neutron capture therapies due to its long‐term clinical application and unequivocally obtained success during clinical trials. Boron drug and neutron play an equivalent crucial role in BNCT. Nevertheless, current clinically used l‐boronophenylalanine (BPA) and sodium borocaptate (BSH) suffer from large uptake dose and low blood to tumor selectivity, and that initiated overwhelm screening of next generation of BNCT agents. Various boron agents, such as small molecules and macro/nano‐vehicles, have been explored with better success. In this featured article, different types of agents are rationally analyzed and compared, and the feasible targets are shared to present a perspective view for the future of BNCT in cancer treatment. This review aims at summarizing the current knowledge of a variety of boron compounds, reported recently, for the application of BCNT. [ABSTRACT FROM AUTHOR]

Radiation therapy has been widely used in the clinical treatment of tumors. Due to the low radiation absorption of tumors, a high dose of ionizing radiation is often required during radiotherapy, which causes serious damage to normal tissues near tumors. Boron neutron capture therapy (BNCT) is more targeted than conventional radiotherapy. To improve the therapeutic effect of cancer, albumin was selected as the drug carrier to wrap the fluorescent tracer boron drug BS‐CyP and prepare the nanoparticles. Then, we developed a novel tumor‐targeting nano‐boron drug by using hyaluronic acid to modify the nanoparticles. We found that BS‐CyP albumin nanoparticles modified with hyaluronic acid effectively delayed drug release and enhanced the aggregation, in tumors, showing good safety with no obvious toxicity to cells and mice. This study confirmed the advantages of boron drugs modified with hyaluronic acid targeting tumors and may provide a reference for BNCT. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy is based on a nuclear reaction between the nonradioactive isotope boron‐10 and either low‐energy thermal neutrons or high‐energy epithermal neutrons, which generate high linear energy transfer α particles and a recoiled lithium nucleus (7Li) that selectively destroys the DNA helix in tumor cells. Boron neutron capture therapy is an emerging procedure aimed at improving the therapeutic ratio for the traditional treatment of various malignancies, which has been studied clinically in a variety of diseases, including glioblastoma, head and neck cancer, cutaneous melanoma, hepatocellular carcinoma, lung cancer, and extramammary Paget's disease. However, boron neutron capture therapy has not been clinically performed for urological cancers, excluding genital extramammary Paget's disease that appeared at the scrotum to penis area. In this review, we aimed to provide an updated summary of the current clinical literature of patients treated with boron neutron capture therapy and to focus on the future prospects of boron neutron capture therapy for urological cancers. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) is considered to have potential for cancer therapy based on the nuclear reaction between boron (10B) atoms and thermal neutrons, yielding 4He2+ (α) and 7Li3+ ions. These heavy particles induce the destruction of biomolecules within short path length of 5–9 μm, resulting in a limited cytotoxic effect to 10B‐containing cells. Herein, we report on the design and synthesis of DNA‐targeting BNCT agents equipped with homo‐ and hetero‐dimeric macrocyclic polyamine units and their Zn2+ complexes. It was hypothesized that the dizinc(II) complexes of these ligands would recognize two adjacent thymidines (thymidyl(3'–5')thymidine), resulting in an efficient contact with DNA and an efficient breakdown of DNA upon thermal neutron irradiation. To test this hypothesis, we performed a DNA interaction study and a biological evaluation such as cytotoxicity and intracellular uptake activity using cancer and normal cells. BNCT experiments utilizing the corresponding 10B‐enriched compounds were also conducted. [ABSTRACT FROM AUTHOR]

Cardiovascular diseases (CVDs) like hypertension are a major cause for death worldwide. In the cardiovascular tissue, the endothelin system—consisting of the receptor subtypes A (ETAR) and B (ETBR) and the mixed agonist endothelin 1 (ET‐1)—is a major key player in the regulation of vascular tone and blood pressure. Tight control of this system is required to maintain homeostasis; otherwise, the endothelin system can cause severe CVDs like pulmonary artery hypertension. The high sequence homology between both receptor subtypes limits the development of novel and selective ligands. Identification of small differences in receptor–ligand interactions and determination of selectivity constraints are crucial to fine‐tune ligand properties and subsequent signaling events. Here, we report on novel ET‐1 analogs and their detailed pharmacological characterization. We generated simplified ET‐1‐derived monocyclic peptides to provide an accessible synthesis route. By detailed in vitro characterization, we demonstrated that both G protein signaling and the subsequent arrestin recruitment of activated ETBR remain intact, whereas activation of the ETAR depends on the intramolecular ring size. Increasing of the intramolecular ring structure reduces activity at the ETAR and shifts the peptide toward ETBR selectivity. All ET‐1 analogs displayed efficient ETBR‐mediated signaling by G protein activation and arrestin 3 recruitment. Our study provides in‐depth characterization of the ET‐1/ETAR and ET‐1/ETBR interactions, which has the potential for future development of endothelin‐based drugs for CVD treatment. By identification of Lys9 for selective labeling, novel analogs for peptide‐mediated shuttling by ET‐1 are proposed. [ABSTRACT FROM AUTHOR]

Due to special non‐metallic polar bond between the III group (with certain metallic properties) element boron (B) and the V group element nitrogen (N), boron nitride (BN) has unique physical and chemical properties such as strong high‐temperature resistance, oxidation resistance, heat conduction, electrical insulation and neutron absorption. Its unique lamellar, reticular and tubular morphologies and physicochemical properties make it attractive in the fields of adsorption, catalysis, hydrogen storage, thermal conduction, insulation, dielectric substrate of electronic devices, radiation protection, polymer composites, medicine, etc. Therefore, the synthesis and properties of BN derived materials become the main research hotspots of low‐dimensional nanomaterials. This paper reviews the synthetic methods, overall properties, and applications of BN nanostructures and nanocomposites. In addition, challenges and prospect of this kind of materials are discussed. [ABSTRACT FROM AUTHOR]

Specifically addressing cell surface molecules on cancer cells facilitates targeted cancer therapies that offer the potential to selectively destroy malignant cells, while sparing healthy tissue. Thus, undesired side‐effects in tumor patients are highly reduced. Peptide‐binding receptors are frequently overexpressed on cancer cells and therefore promising targets for selective tumor therapy. In this review, peptide‐binding receptors for anti‐cancer drug delivery are summarized with a focus on peptide ligands as delivery agents. In the first part, some of the most studied peptide‐binding receptors are presented, and the ghrelin receptor and the Y1 receptor are introduced as more recent targets for cancer therapy. Furthermore, nonpeptidic small molecules for receptor targeting on cancer cells are outlined. In the second part, peptide conjugates for the delivery of therapeutic cargos in cancer therapy are described. The essential properties of receptor‐targeting peptides are specified, and recent developments in the fields of classical peptide‐drug conjugates with toxic agents, radiolabeled peptides for radionuclide therapy, and boronated peptides for boron neutron capture therapy are presented. [ABSTRACT FROM AUTHOR]

Dodecaborate anions represent a suitable boron source for boron neutron capture therapy (BNCT). Sugar derivatives of dodecaborate have been prepared through the ring‐opening reaction of cyclic oxonium ions by alkoxide nucleophiles. According to this general approach, a convenient and short synthesis of three derivatives of dodecaborate‐sugar conjugates is herein reported. Glucose, galactose and fructose have been chosen for their expected preferential uptake by tumor cells compared to healthy cells. The free hydroxyl group of isopropylidene protected sugars was exploited as nucleophile to open a dodecaborate cyclic oxonium salt, giving products containing a spacer between the sugar and the boron cluster. Deprotection of the sugar moiety in acidic conditions gave the desired compounds in excellent yield. [ABSTRACT FROM AUTHOR]

A brain tumour is amongst most devastating and challenging condition to overcome with suitable treatment as the drug has to cross the blood–brain barrier (BBB) with several physiological barriers like opsonisation by the reticuloendothelial system. Presently various techniques such as surgical, chemotherapeutic agents, and radiotherapy techniques have performed to extend the lifespan of patients diagnosed with glioblastoma, which did not maximise the overall survival of patients with a tumour. Nanotechnology is relied upon to diminish the requirement for intrusive methods for conveyance of therapeutics to the central nervous system. Colloidal nanocarriers sizing range 1–1000 nm have been utilised to cross BBB delivers the drug at cell levels with enhanced bioavailability and reduced toxicity. However, solid lipid nanoparticles (SLNs) are considered a highly flexible carrier for more successful remedially in brain tumour. The treatment of a brain tumour via SLNs is gaining greater potency due to its inimitable size and lipidic nature. This review focuses and represents the current strategies of SLNs in the brain tumour treatment with appropriate techniques adopted are highlighted. Based on this review, the authors concluded that SLNs embrace exclusive promising lipidic nanocarrier that could be utilised to target a brain tumour effectively. [ABSTRACT FROM AUTHOR]

Boronated molecular systems can be applied to boron neutron capture therapy (BNCT). Among these systems, carborane‐containing phthalocyanines (Pcs) are the most promising BNCT agents. Herein we report the new zinc (II) complex of the hexacationic Pc 6, which has been obtained as iodide salt through quaternization of the neutral precursor with methyl iodide. Compound 6 was synthesized over a sequence of four steps. The complex, and its precursors as well, were characterized by a combination of spectroscopic techniques, and their structures assessed by 1H, 13C, 11B, and two‐dimensional NMR spectroscopy experiments. Together with a marked tendency to aggregate, 6 showed appreciable solubility in water. Singlet oxygen quantum yield (ΦΔ) of 0.38, and fluorescence quantum yield (ΦF) of 0.13 were obtained for 6 in a DMF solution. The complex proved to be very effective in enriching UMR‐106 cells with 10B, showing very good performance even in case of very low concentrations exposure, i. e. 1 ppm, that moreover resulted in a mild cytotoxic effect. Such a feature can be related to the polycationic nature of the complex, and hence to the well‐known propensity of positively charged species to enter the cellular membrane or to adhere to its external surface. [ABSTRACT FROM AUTHOR]

After uptake by U87 MG and A375 cancer cells, cobaltabisdicarbollide [COSAN]− distributes between membrane and nucleus and presents no relevant cytotoxicity against both cell lines even for long incubation times. The cytotoxicity of Na[COSAN] was also tested towards one normal cell line, the V79 fibroblasts, in order to ascertain the noncytotoxic profile of the compound. As the cell's nucleus contains DNA, the interaction between [COSAN]− and double‐stranded calf thymus DNA (CT‐dsDNA) has been investigated. There is a strong interaction between both molecules forming a nanohybrid CT‐dsDNA‐[COSAN] biomaterial, which was fully characterized. Moreover, Na[COSAN] shows characteristic redox peaks ascribed to the oxidation/reduction of Co3+/2+ at a formal potential of −1.444 V and it can be accumulated at a surface‐immobilized DNA layer of glassy carbon electrodes. The equilibrium surface‐binding constants (Kox/Kred), which confirm that [COSAN]− interacts with DNA by an intercalative or electrostatic mode, depending on the ionic strength of the solution, were estimated. In addition, high binding affinity of Na[COSAN] to proteins was observed by 11B{1H} NMR and confirmed in vivo. Finally, biodistribution studies of [COSAN]− in normal mice were run. After administration, Na[COSAN] was distributed into many organs but mainly accumulated in the reticuloendothelial system (RES), including liver and spleen. After 1 h, the formation of aggregates by plasma protein interaction plays a role in the biodistribution profile; the aggregates accumulate mostly in the lungs. Na[COSAN], which displays low toxicity and high uptake by relevant cancer cells accumulating boron within the nucleus, could act as a suitable compound for further developments as boron neutron capture therapy (BNCT) agents. Bioactive metallacarborane: The noncytotoxic profile of Na[3,3′‐M(1,2‐closo‐C2B9H11)2], [COSAN]−, has been demonstrated on V79 fibroblast cells and its biodistribution in normal mice reported. Pristine [COSAN]− molecules enter the cytoplasm of the cell and reach the nucleus. The strong interaction between Na[COSAN] and double‐stranded calf thymus DNA (CT‐dsDNA) has been revealed (see graphic) and the formed nanohybrid biomaterial fully characterized. [ABSTRACT FROM AUTHOR]

Abstract: The reaction of n‐C8H17B[N(Me)SiMe3]2 (1) with n‐C8H17BCl2 (2 a) yielded, instead of a linear poly(iminoborane), the aminoborane n‐C8H17B(Cl)N(Me)SiMe3 (4) and after cyclotrimerization the borazine cyclo‐(n‐C8H17BNMe)3 (6). Side reactions that result in borazine formation were effectively suppressed if 1,3‐bis(trimethylsilyl)‐1,3,2‐diazaborolidines 7 were employed as co‐monomers in combination with dichloro‐ or dibromoboranes 2 or 8, respectively. Silicon/boron exchange polycondensation led to oligo(iminoborane)s 11 a,b,ac,d. Alternative synthetic routes to such species involve Sn/B exchange of 1,3‐bis(trimethylstannyl)‐2‐n‐octyl‐1,3,2‐diazaborolidine (16) and n‐C8H17BBr2 (8 a), and the initiated polycondensation of the dormant monomer 14 in the presence of a Brønsted acid (HCl, HOTf, or HNTf2; Tf=trifluoromethylsulfonyl). Although an attempt to obtain an oligo‐/poly(iminoborane) with phenyl side groups yielded only insoluble material, the incorporation of aryl groups was proven for a derivative with both phenyl and n‐octyl boron substituents (11 ac), as well as for a derivative with 4‐n‐butylphenyl side groups (11 d). The highest‐molecular‐weight sample obtained was 11 ac. Featuring about 18 catenated BN units, on average, this is the closest approach to a poly(iminoborane) known. [ABSTRACT FROM AUTHOR]

No abstract is available for this article. [ABSTRACT FROM AUTHOR]

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The efficacy of boron neutron capture therapy relies on the selective delivery of boron carriers to malignant cells. p-Boronophenylalanine ( BPA), a boron delivery agent, has been proposed to be localized to cells through transporter-mediated mechanisms. In this study, we screened aromatic amino acid transporters to identify BPA transporters. Human aromatic amino acid transporters were functionally expressed in Xenopus oocytes and examined for BPA uptake and kinetic parameters. The roles of the transporters in BPA uptake were characterized in cancer cell lines. For the quantitative assessment of BPA uptake, HPLC was used throughout the study. Among aromatic amino acid transporters, ATB0,+, LAT1 and LAT2 were found to transport BPA with Km values of 137.4 ± 11.7, 20.3 ± 0.8 and 88.3 ± 5.6 μM, respectively. Uptake experiments in cancer cell lines revealed that the LAT1 protein amount was the major determinant of BPA uptake at 100 μM, whereas the contribution of ATB0,+ became significant at 1000 μM, accounting for 20-25% of the total BPA uptake in MCF-7 breast cancer cells. ATB0,+, LAT1 and LAT2 transport BPA at affinities comparable with their endogenous substrates, suggesting that they could mediate effective BPA uptake in vivo. The high and low affinities of LAT1 and ATB0,+, respectively, differentiate their roles in BPA uptake. ATB0,+, as well as LAT1, could contribute significantly to the tumor accumulation of BPA at clinical dose. [ABSTRACT FROM AUTHOR]

Boron neutron capture therapy (BNCT) of cancer depends on the selective delivery of a sufficient number of boron-10 (10B) atoms to individual tumour cells. Cell killing results from the 10B (n, α)7Li neutron capture and fission reactions that occur if a sufficient number of 10B atoms are localized in the tumour cells. Intranuclear 10B localization enhances the efficiency of cell killing via damage to the DNA. The net cellular content of 10B atoms reflects both bound and free pools of boron in individual tumour cells. The assessment of these pools, delivered by a boron delivery agent, currently cannot be made at subcellular-scale resolution by clinically applicable techniques such as positron emission tomography and magnetic resonance imaging. In this study, a secondary ion mass spectrometry based imaging instrument, aCAMECAIMS3f ion microscope, capable of 500 nm spatial resolution was employed. Cryogenically prepared cultured human T98G glioblastoma cells were evaluated for boron uptake and retention of two delivery agents. The first, L-p-boronophenylalanine (BPA), has been used clinically for BNCT of high-grade gliomas, recurrent tumours of the head and neck region and melanomas. The second, a boron analogue of an unnatural amino acid, 1-amino-3-borono-cyclopentanecarboxylic acid (cis-ABCPC), has been studied in rodent glioma and melanoma models by quantification of boron in the nucleus and cytoplasm of individual tumour cells. The bound and free pools of boron were assessed by exposure of cells to boron-free nutrient medium. Both BPA and cis-ABCPC delivered almost 70% of the pool of boron in the free or loosely bound form to the nucleus and cytoplasm of human glioblastoma cells. This free pool of boron could be easily mobilized out of the cell and was in some sort of equilibrium with extracellular boron. In the case of BPA, the intracellular free pool of boron also was affected by the presence of phenylalanine in the nutrient medium. This suggests that itmight be advantageous if patients were placed on a low phenylalanine diet prior to the initiation of BNCT. Since BPA currently is used clinically for BNCT, our observations may have direct relevance to future clinical studies utilizing this agent and provides support for individualized treatment planning regimens rather than the use of fixed BPA infusion protocols. [ABSTRACT FROM AUTHOR]

In this study, the Huisgen reaction has been used to functionalise a carborane cage with a lipophilic moiety and a 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) ligand to obtain a new Gd boron neutron-capture therapy (BNCT)/magnetic resonance imaging (MRI) agent. The introduction of the triazole units has been accomplished under both heterogeneous conditions, by the use of a Cu-supported ionic-liquid catalyst, and homogeneous conditions. The ability of the Gd complex of the synthesised ligand to form stable adducts with low-density lipoproteins (LDLs) has been evaluated and then MRI has been performed on tumour melanoma cells incubated in the presence of a Gd-complex/LDL imaging probe. It has been concluded that the high amount of intracellular boron necessary to perform BNCT can be reached even in the presence of a relatively low-boron-containing LDL concentration. [ABSTRACT FROM AUTHOR]

The conjugation of peptides to porphyrins and related tetrapyrrole based macrocycles have extended their applications in biological systems, where the photophysical properties of these molecules and their ability to coordinate metals can be exploited for detecting and opposing to the onset of important diseases. This review presents a survey of the published literature over last years on biomedical applications of these hybrid compounds, mostly in the field of photodynamic therapy (PDT), but also in sensing key metabolites and peculiar structures of biomolecules in living systems. Peptides based strategies to improve the efficacy of the photosensitizer (PS) in PDT will be discussed, as well as solutions to overcome some limitations recently emerged in the use of peptides as delivery vehicles. An overview on possible application of porphyrin–peptide conjugates in detection of biomarkers of physiological and pathological states will be also presented. [ABSTRACT FROM AUTHOR]