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Myristic acid-palmitic acid-tetradecanol/expanded graphite (MA-PA-TD/EG) and myristic acid-stearic acid-lauric acid/ expanded graphite (MA-SA-LA/EG) were obtained. MA-PA-TD/EG and MA-SA-LA/EG for the optimum mass ratio of 8:1 were investigated by DSC, FT-IR, TG, and SEM, and it was shown that MA-PA-TD and MA-SA-LA phase change materials were evenly distributed in expanded graphite through capillary force. Phase transition temperatures of MA-PA-TD/EG and MA-SA-LA/EG before and after cooling and heating cycles were 34.14, 34.39 °C and 30.21, 30.33 °C, respectively, and MA-PA-TD/EG and MA-SA-LA/EG had good stability. On the other hand, MA-PA-TD/EG was 67% faster than that of MA-PA-TD during solid-liquid phase change, and MA-SA-LA/EG was 63% faster than that of MA-SA-LA. Meanwhile, MA-PA-TD/EG and MA-SA-LA/EG had good thermal stability and heat storage according to thermogravimetric experiments. Therefore, MA-PA-TD/EG and MA-SA-LA/EG are suitable for practical application in buildings.

Photodynamic therapy (PDT) is strongly O2 dependent. Therefore, its therapeutic effects are seriously hindered in hypoxic tumors. Red blood cells are responsible for delivering O2 in the blood. In this manuscript, biomimetic red blood cells (BRBCs) were exploited using a layer-by-layer assembly method, using Fe3O4@CuO, oxyhemoglobin (OxyHb), a photosensitizer and a photo-cross linked acrylate modified hyaluronic acid (HA) gel shell. The Fe3O4@CuO core has very high OxyHb loading efficiency (the adsorption capacity of Fe3O4@CuO for OxyHb is derived to be 0.99 mg mg-1) to ensure a sufficient O2 supply. OxyHb was protected well by the HA shell in order to avoid O2 release during the delivery process in blood before arrival at the tumor tissue. The HA shell protection can be eliminated in position at the tumor to trigger O2 release through hyaluronidase (HAase) triggered HA degradation. Furthermore, Fe3O4 in the nanosystem can provide magnetic field assisted tumor targeting and magnetic resonance imaging of the tumor. Therefore, this work presents a highly efficient all-in-one biomimetic nanomedicine approach to overcome hypoxia and achieve tumor targeting theranostics.

Multimode sensing has attracted extensive attention because they provide more than one transduction channel, thus improving accuracy and sensitivity. Due to the structural diversity, MnO2 nanosheets and nanoneedles were successively obtained via one-step redox reaction and different self-assembly methods. MnO2 nanosheets possess outstanding optical properties including extremely strong resonance Rayleigh scattering (RRS) and absorbance signal, and were selected as a dual-mode sensing material. Inspired by the selectivity of alkaline phosphatase (ALP) towards dephosphorylate ascorbic acid 2-phosphate (AAP) to generate ascorbic acid (AA), which has the ability to decompose MnO2 nanosheets along with optical signals and colour change, a dual-mode optical ALP sensing platform has been designed. Therefore, MnO2 nanosheets can serve as colorimetric probes by directly visualizing the colour variation with bare eyes. Moreover, the detection limit obtained by the RRS sensing mode can be as low as 0.17 mU L−1, which is far superior to that obtained by previously reported methods. The strategy not only has good feasibility and sensitivity, but also shows good prospects for a series of ALP-extended sensing applications.

The common existence of hypoxia within the tumor microenvironment severely restricts the efficacy of photodynamic therapy (PDT), which is attributed to the fact that the PDT process is strongly oxygen (O2) dependent. Here, a multifunctional composite (named CPCG), which combines polyethylene glycol (PEG) functionalized cerium oxide nanoparticles (CeO2) with photosensitizer chlorin e6 (Ce6) and glucose oxidase (GOx), is reported for generating O2 within the tumor microenvironment by the dual-path hydrogen peroxide (H2O2)-modulated ways to ameliorate hypoxia, thereby enhancing the PDT efficiency. This process is realized based on the dual enzyme-like activity of CeO2. The first modulated way is to transform the superoxide anion (O2˙-) into H2O2 by the superoxide dismutase-like activity of CeO2. The second modulated way is to decompose glucose into H2O2 through the catalysis of GOx. Subsequently, H2O2 generated from the above dual modulated ways can further produce O2via the catalase-like activity of CeO2. Additionally, the depletion of glucose could impede the nutrient supply to obtain starvation therapy. Both in vitro and in vivo experiments indicate that the CPCG composite could enhance the efficacy of photodynamic/starvation synergistic therapy. Therefore, this strategy offers great potential to modulate the O2 level in the tumor microenvironment for better therapeutic outcomes, and can act as a promising candidate in photodynamic/starvation synergistic therapy.

Photodynamic therapy (PDT) has been applied in cancer treatment by utilizing reactive oxygen species (ROSs) to kill cancer cells. However, a high concentration of reduced glutathione (GSH) is present in cancer cells and can consume ROSs and sharply reduce the PDT activity. To address this problem, herein, we synthesized a thymine modified Zn phthalocyanine (ZnPc, a monomer and an active form for PDT) and prepared its nanoparticle form (an aggregator and an inactive form) with Hg2+ providing the driving force for the “thymine–Hg2+–thymine” interaction. The nanoparticles could remain in the inactive form during the delivery process in blood. Once endocytosed by cancer cells, the nanoparticles are disintegrated, and deprived of Hg2+ by intracellular GSH, which decreases the level of GSH. Simultaneously, the activity of the released monomer ZnPc is recovered and high PDT activity is observed.

Hypoxia in solid tumors hinders the efficacy of photodynamic therapy (PDT). The route of generation of adenosine triphosphate (ATP) in hypoxic tumor cells comprises ineffective glycolysis processes, but ATP is crucial for rapid and uncontrolled growth and division. ATP depletion would inhibit DNA replication and glutathione (GSH) biosynthesis, which could inhibit the proliferation of cells and make them sensitive to PDT treatment. In this context, a nanoscale metal-organic framework nanoparticle consisting of Cu2+ and carboxyl-modified zinc phthalocyanine (ZnPc-(COOH)8) ({Cu8(ZnPc-(COOH)8)}n, ZPCN) was designed and prepared. In the dark cycle, ATP could remove Cu2+ from ZPCN and form a copper-ATP complex. ATP in the above complex could be destroyed by a copper-mediated Fenton reaction, which could finally induce ATP depletion to inhibit the proliferation of cells and make them sensitive to PDT treatment. In the light cycle, ZPCN could generate abundant cytotoxic reactive oxygen species to suppress tumor growth. These results demonstrated the potential applicability of the new strategy for achieving tumor treatment in hypoxic conditions by PDT.

An arginine substituted zinc phthalocyanine (ArgZnPc) which is capable of disaggregating at high concentrations in polar non aqueous solvents through concentration-driven hydrogen bond type transformation has been prepared. The ArgZnPc was prepared through a "guanidine meditated self-catalytic ester hydrolysis" reaction. The concentration-driven disaggregation of ArgZnPc was confirmed by UV-Vis absorption spectra, fluoresce emission spectra and lifetimes, and singlet oxygen quantum yields data. This result provides a new way for the disaggregation of aromatic compounds at high concentrations.

Many reports indicated that the cellular uptaken and photodynamic anti-cancer activity of amino group modified phthalocyanine (Pc) could be greatly improved in the acid environment around cancer cells because such Pc could transfer to their hydrochloride protonated form and inhibit the intramolecular photoinduced electron transfer (PET) effect. However, no more researches are carried out to indicate whether this law has the extensive applicability in all kinds of amino modified Phthalocyanines (Pcs). So, here, four amino groups modified Pcs and their hydrochloride or quaternized cationic derivatives, with two kinds of amino groups (phenylamine and benzylamine) substituted were synthesized. Their solubility in aqueous system, cancer cell uptaken ability and photodynamic activities were also systematically compared. Our research results indicated that above law had the extensive applicability in benzylamine amino groups modified Pcs. But for phenylamine amino groups modified ones, the cancer cell uptaken ability and anti-cancer activity of hydrochloride derivatives were obviously decreased comparing with the unmodified Pc because its nitrogen atom was closer to the Pc ring, which would induce its nitrogen atom and the ring to form p–π conjugation system, furthermore, the relatively free state of lone pair electrons of surrounding nitrogen atom leaded to PET strengthening.

The carbon monoxide (CO)-carrying palladium nanosheet (PdNS-CO) was exploited as a photothermally triggered donor of CO. Irradiating material containing PdNS-CO with 808 nm-wavelength light caused a rapid heating of the material, triggering a release of CO. The enhanced permeability and retention (EPR) effect was found to be improved by such released CO and resulted in an increase in the accumulation of PdNS-CO at tumors and hence promoted its use in photothermal therapy (PTT) using a low laser power density.

Reactive oxygen species (ROS) generated during photodynamic therapy (PDT) can trigger autophagy. However, little research is focused on whether there is a synergistic anticancer effect with PDT if extra autophagy promoter or inhibitor is added. Here, it is found that autophagy promotion significantly enhances the PDT activity to cancer cells. Based on this preliminary result, a ROS-sensitive self-assembled dendrimer nanoparticle is exploited as a carrier to codeliver an autophagy promoter (rapamycin, Rapa) and photosensitizer (phthalocyanine, Pc) to the tumor. After entrapped by cancer cells and irradiated by light, the ROS generated in PDT process of Pc can trigger nanoparticle destruction to release Rapa, thus initiating the autophagy process and remarkably enhancing the efficacy of PDT, leading to efficient tumor suppression.

In this article, the UV–vis absorption, steady state/time resolved fluorescence spectroscopy and synchronous fluorescence, circular dichrosim (CD) spectroscopy are used to investigate the interaction of artemisinin (QHS) and 9-hydroxy-artemisinin (9-OH QHS) with BHb, respectively. The UV–vis studies present that QHS and 9-OH QHS can disturb the structure of bovine hemoglobin (BHb). Fluorescence data presents that the binding constant of QHS and 9-OH QHS with BHb complex at 298 K is 4.32×105 and 5.98×105 M−1. CD spectra indicate QHS and 9-OH QHS can change the conformation of BHb. The comparison results suggest that the binding of BHb with 9-OH QHS is more stable and stronger than QHS, which means the structure modification of 9-OH QHS is meaningful.

A series of hypocrellin A (HA) self-assembled nanostructures were prepared by controlling the charge properties of drugs and the ion strength of the environment. Comparative studies with nanostructures and HA have demonstrated that the self-assembled effect on the HA molecule significantly enhances its water dispersion ability, 1O2 generation efficiency and, thereby, the in vitro phototoxicity to human cervical carcinoma (HeLa) cells.

The stable 4 : 1 host–guest complex of phthalocyanine (Pc) and hydroxypropyl-beta-cyclodextrin was designed, computer modeled and prepared. The complex formation can greatly increase water solubility, reactive oxygen generation ability, biocompatibility and, thereby, the in vitro phototoxicity of Pc to cancer cells.

This work reports on the effects of pH (especially base addition) on the properties of two cationic phthalocyanines substituted with amide groups. The absorption spectra, photo-stability, singlet oxygen generation ability and photodegradation of CT DNA of the two cationic phthalocyanines in different pH were studied and compared. Results indicated that the base additive can promote a shift in the amide/imidohydrine balance toward imidohydrine, which resulted in the reduction of aggregate and enhancement of photodynamic activities. This base induced tautomeric transformation could be a novel way to generate low aggregated and high photodynamic efficiency cationic Pcs.

A novel hybrid of graphene oxide (GO) and hypocrellin B (HB) was prepared using a simple noncovalent method. An efficient loading of HB on GO as high as 2 mg/mg was obtained. Mechanism analysis indicated that the π–π stacking interaction is the dominant driving force in the noncovalent interaction between HB and GO. Irradiation of HB and GO hybrid (HB–GO) results in efficient generation of singlet oxygen (1O2). In vitro studies have demonstrated the active uptake of HB–GO into the cytosol of tumor cells. Significant damage to such impregnated tumor cells was observed upon irradiation.

A mechanochemical approach is developed in preparing a series of magnesium–aluminum-layered double hydroxides (Mg–Al-LDHs). This approach includes a mechanochemical process which involved manual grinding of solid salts in an agate mortar and afterwards peptization process. In order to verify the LDHs structure synthesized in the grinding process, X-ray diffraction (XRD) patterns, transmission electron microscopy (TEM) photos and thermogravimetry/differential scanning calorimetry (TG–DSC) property of the product without peptization were characterized and the results show that amorphous particles with low crystallinity and poor thermal stability are obtained, and the effect of peptization is to improve the properties, more accurately, regular particles with high crystallinity and good thermal stability can be gained after peptization. Furthermore, the fundamental experimental parameters including grinding time, the molar ratio of Mg to Al element (defined as R value) and the water content were systematically examined in order to control the size and morphologies of LDHs particles, regular hexagonal particles or the spherical nanostructures can be efficiently obtained and the particle sizes were controlled in the range of 52–130 nm by carefully adjusting these parameters. At last, stunningly uniform Mg–Al-LDHs particles can be synthesized under proper R values, suitable grinding time and high degree of supersaturation.

A facile approach for hemoglobin (Hb) encapsulation in silica nanoparticles (HbSNs) is reported. The results display that the HbSN keeps its structures. The stability of the encapsulated HbSN is significantly increased compared to that of free one at 4 °C in a buffer of pH 7.4. Moreover, the experiments of HbSN catalytic reduction of H 2 O 2 and electrocatalytic reduction of O 2 indicate that the strategy could enhance the activity of Hb, and exhibit promising applications in biosensors, biofuel cell and so on.

Controlled drug release systems can enhance the safety and availability but avoid the side effect of drugs. Herein, the concept of DNA complementary base pairing rules in biology is used to design and prepare a photothermal-triggered drug release system. Adenine (A) modified polydopamine nanoparticles (A-PDA, photothermal reagent) can effectively bind with thymine (T) modified Zinc phthalocyanine (T-ZnPc, photosensitizer) forming A-PDA = T-ZnPc (PATP) complex based on A = T complementary base pairing rules. Similar to DNA, whose base pairing in double strands will break by heating, T-ZnPc can be effectively released from A-PDA after near infrared irradiation-triggered light-thermal conversion to obtain satisfactory photodynamic-photothermal synergistic tumor treatment. In addition, PDA can carry abundant Gd3+ to provide magnetic resonance imaging guided delivery and theranostic function.

The interaction of Zn(II) porphyrin (ZnPP) with colloidal TiO2was studied by absorption and fluorescence spectroscopy. The fluorescence emission of ZnPP was quenched by colloidal TiO2upon excitation of its absorption band. The quenching rate constant (kq) is1.24×1011 M−1 s−1. These data indicate that there is an interaction between ZnPP and colloidal TiO2nanoparticle surface. The quenching mechanism is discussed on the basis of the quenching rate constant as well as the reduction potential of the colloidal TiO2. And the mechanism of electron transfer has been confirmed by the calculation of free energy change(ΔGet)by applying Rehm-Weller equation as well as energy level diagram.

The photocatalytic degradation of Rhodamine B(RhB) on TiO2 nanoparticle modified with porphyrin (Pr) and Fe(III)porphyrin (Fe(III)Pr), which were prepared through the chemisorption method, have been investigated under ultraviolet light and visible light irradiation. The results indicated that the photodegradation of RhB was significantly enhanced in the presence of the Pr/TiO2 or Fe(III)Pr/TiO2 comparing with the nonmodified TiO2 under ultraviolet light, but under visible light, only Pr/TiO2 has remarkable effect.

The surface binding association between a positively charged polymeric complex of hypocrellin A (HA) with La 3+ (La 3+ -HA) and calf thymus DNA (CT DNA) was confirmed by ESR and laser flash photolysis techniques along with UV-Vis absorption and fluorescence emission spectra. This surface binding, in cooperation with the longer triplet excited state lifetime of La 3+ -HA, gave rise to a stronger photodamage of CT DNA both in aerobic and anaerobic conditions by La 3+ -HA compared with HA.

An effective theranostic platform based on porous silica nanoparticles encapsulated with the complex of a photodynamic anticancer drug and graphene quantum dots (GQDs), with the bifunction of multicolor imaging and satisfactory photo-induced anticancer activity, was successfully designed and prepared for in vitro photodynamic therapy (PDT) of superficial cancer.

Graphene oxide (GO) was investigated as a potential drug-delivery system due to its special properties and biocompatibility. Thus far, little has been done to use GO as a photosensitive drug-delivery system and to explore its anticancer activity in vitro in photodynamic therapy applications. Here, a novel GO-hypocrellin A (GO-HA) hybrid was prepared by a simple noncovalent method and its photodynamic activity was studied for the first time. The results showed that an efficient loading amount of HA on GO was as high as 1.0 mg mg(-1) and the stability of the hybrid was superior to that of the free hypocrellin A in aqueous solution. Furthermore, GO-HA can be excited by irradiation with light of appropriate wavelength to generate singlet oxygen, and in vitro experiments illustrated that GO-HA was efficiently taken up by tumor cells, and that light irradiation of such impregnated cells resulted in significant cell death. Thus, these properties of GO-HA could possibly make it especially promising for use in clinical photodynamic therapy.

Heck reaction catalyzed by cobalt hollow nanospheres has been developed; the coupling of alkenes with aryl iodide or aryl bromide in the presence of potassium carbonate provides the corresponding products with moderate to good yields, which reveals obvious advantages such as low-cost catalyst, ligand-free condition, the recyclability of the catalyst and simple experimental operation.

A FRET ratiometric fluorescent probe enabling a fast and highly sensitive response to OP nerve agent mimic DCP within 1 min and with as low as 0.17 ppm concentration detection limit has been developed. Moreover, the probe exhibits noticeable color changes under UV light and even with the naked eye. It is also demonstrated that it can detect both liquid and gas nerve agents.