Theranostic Effect of Folic Acid Functionalized MIL-100(Fe) for Delivery of Prodigiosin and Simultaneous Tracking-Combating Breast Cancer

The metal organic framework (MOF) member, MIL-100(Fe), is considered as attractive drug nanocarrier that may be due to the great porosity, colloidal stability, and biocompatibility. In the present study, the new electrochemical synthesis procedure was presented for MIL-100(Fe) building block, and secondly, folic acid (FA) was introduced to the structure for assessing its potential targeted ability to be entrapped by folic acid-positive breast cancer cells, MCF-7. Several techniques such as SEM, XRD, and FT-IR were used to characterize synthesized nanostructures. Both MIL-100(Fe) and MIL-100(Fe)/FA nanoparticles were between 50 to 200 nm with a slightly positive net charge with an area of 1350 and 831.84 m2/g, respectively. The prodigiosin (PG) is selected as a model drug for MIL-100(Fe) and MIL-100(Fe)/FA-targeted delivery owing to its natural fluorescence and cancer cell selectiveness. The loading capacity of both nanocarrier was around 40% with 93-97% loading efficacy. Moreover, the pH-sensitive prodigiosin release rate of MIL-100(Fe)@PG and MIL-100(Fe)/FA@PG showed that 69 to 73% of the drug was released after 24 hours in an acidic environment with around 20% unwanted leakage. The anticancer potential MIL-100(Fe)/FA cells showed the improvement of selective index (SI) from 3.21 to 12.48 which means that folic acid acts as an effective ligand. The study of cells treated with fluorescence microscopy and flow cytometry analysis reveals the dependence of the receptor on the nanoparticle through endocytosis. Considering the effects of nanoparticles on healthy cells, MIL-100(Fe) and MIL-100(Fe)/FA nanoparticles can be introduced as targeted drug delivery systems for smart targeting breast cancer cells with minimal side effects.

Bright green fluorescence of Asian paper wasp nests

An exceptionally bright fluorescent biomatter was discovered when exploring, with UV-A light, the nests of several oriental paper wasp species of the genus Polistes , a genus of diurnal social insects. Fluorescence spectra of the cocoon cap membranes revealed narrow emission bands in the green range of the visible spectrum. Large Stokes shifts of around 160 nm and high fluorescence quantum yields of up to 35% were measured. Transmission spectra were recorded in order to estimate the contribution of the fluorescence to the visible light transmitted through the cocoon cap membrane. The nest fluorescence of the Vietnamese wasps was compared with a European and an American species. Potential biological functions of these interesting fluorescence properties of the studied biomaterial are discussed. The discovery of this striking example of a fluorescent terrestrial biomaterial may contribute to the debate on adaptive biological functions of natural fluorescence and falls in line with the growing interest in biodiversity and bio-inspiration.

Invisible dye tracing – an efficient technique for study of groundwater channels

We studied excitation spectra of uranine fluorescence in eluates from charcoal traps saturated in cave waters and in reference uranine solutions and found that the most appropriate excitation wavelength is 295±5 nm, because it excites fluorescence of uranine many times stronger than fluorescence of natural fluorescent compounds in groundwater. This allows us to lower the detection limit of uranine fluorescence with one order of magnitude, even below the level of natural fluorescence of karst waters at integral UV excitation.

Removal of Pharmaceuticals, Toxicity and Natural Fluorescence by Ozonation in Biologically Pre-Treated Municipal Wastewater, in Comparison to Subsequent Polishing Biofilm Reactors

Ozonation followed by a polishing moving bed biofilm reactor (MBBR) was implemented in pilot and laboratory to remove the residual pharmaceuticals and toxicity from wastewater effluent, which was from a pilot hybrid system of MBBR and activated sludge, receiving municipal wastewater. The delivered ozone dosages achieving 90% pharmaceutical removal were determined both in pilot and laboratory experiments and they were normalised to dissolved organic carbon (DOC), illustrating our findings were comparable with previously published literature. During wastewater ozonation, the intensity of natural fluorescence was found to be greatly associated with the concentrations of the studied pharmaceuticals. In pilot experiments, toxicity, measured by Vibrio fischeri, increased after ozonation at delivered ozone dosages at 0.38–0.47 mg O3/mg DOC and was completely removed by the subsequent polishing MBBR. Laboratory experiments verified that the polishing MBBR was able to remove the toxicity produced by the ozonation.

Bio-optical characterization of the waters of the Bay of La Paz, southern Gulf of California, during late spring 2004

Information on selected bio-optical properties and primary production values of the waters of the Bay of La Paz, southern Gulf of California, is reported during June 2004, a region characterized to have very rich biodiversity, including endemic and endangered species, with high ecological relevance. In-situ measurements of natural fluorescence and photosynthetically available radiation (PAR) enabled the subsequent calculation of the incident irradiance (E0), the light extinction coefficient (k), compensation depth (Zc) and critical depth (Zcr). The results suggest the presence of light propitious conditions for phytoplankton community growth and net primary production, which are highly significant for the potential development of models of light penetration, ocean color, primary productivity, and analyses of organic carbon energy flow.

Characterization of Lignin

Lignin is a complex organic compound crucial to the structural tissues of vascular plants, such as trees. The cyclic structure and aromaticity of lignin give it significant potential to be used as a renewable and safe replacement for toxic aromatic compounds in chemical and industrial processes. The purpose of this experiment was to characterize lignin, specifically the particle diameter and zeta potential, using both the Zetasizer Nano ZSP and the ImageJ image processing software, and to compare the accuracy of both measurement methods. Due to the natural fluorescence of lignin, a fluorescence microscope is used to capture images of lignin particles. By having a known distance and the scale of measurement, with ImageJ it is possible to calculate distances, such as the diameters of particles in images. The Zetasizer Nano ZSP is a device capable of measuring both particle diameter and zeta potential, which is the electrical charge existing on particles suspended in a medium. Small amounts of lignin, in powder form, are placed into scintillation vials with different amounts of distilled water to create 3 different concentrations of sample to measure using the Zetasizer. Between 10-15mL of sample are placed into specialized measurement cells and put into the Zetasizer. Multiple measurements are conducted and averaged to achieve accurate results. The measured zeta potential value is indicative of the stability of the lignin. If the value of zeta potential is higher than 30mV, negative or positive, it has a high stability and low reactivity. The average values of zeta potential measured by the Zetasizer ranged from -27mV to -21mV. The particle diameter is important in characterization, as the smaller and more distributed the particles are, there is a larger surface area for reactions to occur. Average particle diameter measured by the Zetasizer ranged from 926-976µm. The results from the Zetasizer Nano ZSP are more accurate than those from the ImageJ software, as ImageJ allows for a substantial amount of human error to impact the results. The outcomes help direct future experiments using lignin and beneficial to future research concerning lignin and its potential.

Hyperspectral imaging as a tool for assessing coral health utilising natural fluorescence

Fluorescent proteins are a crucial visualisation tool in a myriad of research fields including cell biology, microbiology and medicine. Fluorescence is a result of the absorption of electromagnetic radiation at one wavelength and its reemission at a longer wavelength. Coral communities exhibit a natural fluorescence which can be used to distinguish between diseased and healthy specimens, however, current methods, such as the underwater visual census, are expensive and time-consuming constituting many manned dive hours. We propose the use of a remotely operated vehicle mounted with a novel hyperspectral fluorescence imaging (HyFI) “payload” for more rapid surveying and data collection. We have tested our system in a laboratory environment on common coral species including Seriatopora spp., Montipora verrucosa, Montipora spp., Montipora capricornis, Echinopora lamellose, Euphyllia ancora, Pocillopora damicornis and Montipora confusa. With the aid of hyperspectral imaging, the coral specimens’ emission wavelengths can be accurately assessed by capturing the emission spectra of the corals when excited with light emitting diodes (395–405 and 440 nm). Fluorescence can also provide an indicator of coral bleaching as shown in our bleaching experiment where we observe fluorescence reduction alongside coral bleaching.