Noyes-Whitney Dissolution Model-Based pH-Sensitive Slow Release of Paclitaxel (Taxol) from Human Hair-Derived Keratin Microparticle Carriers

This paper describes a convenient and straightforward method developed to extract keratin particles (KPs) from human hair. It also involves their characterization by several methods and encapsulation of the anticancer drug Paclitaxel (Taxol) within them, aiming for targeted delivery to cancerous sites and slow release at their vicinity. The KPs obtained were in micrometer in size. They are capable of encapsulating Taxol within them with a high encapsulation efficiency of 56% and a drug loading capacity of 2.360 g of Taxol per g keratin. As revealed by the SEM elemental analysis, KPs do not contain any toxic metal ion, and hence, they pose no toxicity to human cells. The pH-dependent release kinetics of the drug from KPs indicates that the drug is released faster when the pH of the solution is increased in the 5.0 to 7.0 pH range. The release kinetics obtained is impressive, and once targeted to the cancerous sites, using cancer directing agents, such as folic acid; a glutamate urea ligand known as DUPA; aminopeptidase N, also known as CD13; and FAP-α-targeting agents, the slow release of the drug is expected to destroy only the cancerous cells. The Noyes-Whitney dissolution model was used to analyze the release behavior of Taxol from KPs, which shows excellent fitting with experimental data. The pH dependence of drug release from keratin is also explained using the 3-D structures and keratin stability at different pH values

Cement Types, Composition, Uses and Advantages of Nanocement, Environmental Impact on Cement Production, and Possible Solutions

We first discuss cement production and special nomenclature used by cement industrialists in expressing the composition of their cement products. We reveal different types of cement products, their compositions, properties, and typical uses. Wherever possible, we tend to give reasons as to why a particular cement type is more suitable for a given purpose than other types. Cement manufacturing processes are associated with emissions of large quantities of greenhouse gases and environmental pollutants. We give below quantitative and qualitative analyses of environmental impact of cement manufacturing. Controlling pollution is a mandatory legal and social requirement pertinent to any industry. As cement industry is one of the biggest CO2 emitters, it is appropriate to discuss different ways and means of CO2 capture, which will be done next. Finally, we give an account of production of nanocement and advantages associated with nanocement. Nanofillers such as nanotitania, nanosilica, and nanoalumina can be produced in large industrial scale via top-down approach of reducing size of naturally available bulk raw materials to those in the nanorange of 1 nm–100 nm. We mention the preparation of nanotitania and nanosilica from Sri Lankan mineral sands and quartz deposits, respectively, for the use as additives in cement products to improve performance and reduce the amount and cost of cement production and consequent environmental impacts. As of now, mineral sands and other treasures of minerals are exported without much value addition. Simple chemical modifications or physical treatments would add enormous value to these natural materials. Sri Lanka is gifted with highly pure quartz and graphite from which silica and graphite nanoparticles, respectively, can be prepared by simple size reduction processes. These can be used as additives in cements. Separation of constituents of mineral sands is already an ongoing process

Synthesis of cisplatin encapsulated Zinc oxide nanoparticles and their application as a carrier in targeted drug delivery

Cisplatin is a frequently used anticancer drug that has been developed as the first platinum-based anticancer drug. The cis configuration enables the coordination complex to be covalently binding to one or two DNA strands and thus cross-linking the DNA strands, causing the cells to die in a programmed manner. Cisplatin is administered as an IV infusion in saline solution for medication of solid malignity. Anticancer drugs usually have a variety of side effects, but an encapsulation of the drug in a suitable host material minimizes the side effects while improving the efficacy of the drug due to its slow release only at the target. The aim of this research is to develop a simple, but effective mechanism for the preparation of porous zinc oxide nanoparticles (PZnO NPs) using the forced hydrolysis method reaction of zinc acetate dihydrate with deionized water in diethylene glycol (DEG) media. This synthesized PZnO NPs were then characterized by Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX), Fourier Transform Infrared Spectroscopy (FT-IR), Particle Size Analysis and Powder X-Ray Diffraction (PXRD). The encapsulation of cisplatin within the porous zinc oxide nanoparticles was confirmed by X-ray Fluorescence (XRF), SEM, EDX, and FT-IR studies. Our results show that the synthesized nanoparticles have the hexagonal wurtzite structure as confirmed by PXRD. The average particle size as determined by light scattering is 52.4 ± 0.1 nm SEM images show porous spherical morphology with aggregated particles. XRF data of the cisplatin encapsulated product show a Pt: Cl ratio of 1:2 showing cisplatin encapsulation without any fragmentation or other chemical change. The presence of NH3 in the encapsulated product is also apparent from FT-IR data. The encapsulation of the anti-cancer drug cisplatin to PZnO NPs and its pH dependence on the release of the drug from PZnO NPs was studied by measuring the amount of Pt released as a function of the time which was done using Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) at λmax 265.94 nm. The encapsulation efficiency of Cisplatin into PZnO NPs was found to be 50.52%. The percentage of Cisplatin released from PZnO NPs during the first 7 hours was < 6.30% in the acetate/phosphate buffer at pH 4.0, 5.0, 6.0, 7.0 and 8.0. The maximum release of 8.64% was observed at pH = 6.0 after 24 hours

Removal of Phosphate from Aqueous Solutions Using Chemically Synthesized Vaterite Polymorph of Porous Calcium Carbonate Nanoparticles under Optimized Conditions

Eutrophication is one of the most adverse impacts of nutrient contamination of water bodies where the phosphate is considered to be the primary limiting factor. The vaterite polymorph of porous calcium carbonate nanoparticles (VPCCNPs) were synthesized and used to remove orthophosphate ions in water. In this study, the VPCCNPs were synthesized chemically, using calcium acetate and sodium bicarbonate in a water-ethylene glycol media, at a temperature of 100°C, in a reaction time of 24 hours. Synthesized nanoparticles were characterized by X-ray diffractometry to confirm that the crystalline phase of calcium carbonate formed is spherical vaterite polymorph. Scanning electron microscopy coupled with energy dispersive X-ray analysis further confirms the spherical shape of the vaterite nanoparticles and the presence of only calcium, carbon, and oxygen thus showing high purity of the synthesized calcium carbonate nanoparticles. The dynamic laser light scattering-based particle size analysis (DLS) shows the average particle size to be 25.5 nm. The Fourier transform infrared spectroscopy was used to find functional groups before and after the adsorption of phosphate by vaterite nanoparticles. The phosphate removal efficiency of synthesized nanoparticles was tested with different concentrations of phosphate solutions (2–80 mg/L), pH levels (5–12), adsorbent dosages (0.025–0.250 g), and contact times (5–120 min). Ion chromatography was used to analyse the phosphate concentrations in water samples. The maximum phosphate removal percentage of 100% was obtained with 50 mL of 2 mg/L phosphate solution and 0.15 g of the synthesized nanoparticle. Adsorption data were well fitted with the Langmuir adsorption isotherm model and the pseudo-second-order kinetic model with R2 of 0.99 and 0.98 (rate constant -0.083 g g-1 min-1), respectively. The presence of F−, NO3−, and SO42− has no effect on phosphate adsorption since 100% phosphate removal is obtained in the presence of these ions. Furthermore, the particle shows a 100% removal of orthophosphate ions available in eutrophic water regardless of the presence of many other ions in natural water bodies. The study presents a viable option for removing excess phosphate in natural water to desirable levels as a means for controlling eutrophication