The Determination of Metronidazole and Chlorhexidine Gluconate in Metronidazole and Chlorhexidine Lotion by HPLC

Objective “To establish an HPLC method for the determination of metronidazole and chlorhexidine gluconate in metronidazole and chlorhexidine lotion. Method Using Agilent Eclipse-XDB-C18 chromatographic column, with 0.05 mol·L-1 potassium dihydrogen phosphate solution 1000 ml plus 13.2 ml 10% tetrabutylammonium hydroxide aqueous solution (pH adjusted to 3.5 by phosphoric acid)-acetonitrile (77:23) as Mobile phase, detection wavelength 230 nm. Results The two components could be separated well. The linear ranges of metronidazole and chlorhexidine acetate were 36.33~59.04 μg·ml-1 (r = 0.9994) and 35.45~220.11 μg·ml-1 (r = 1).); The average recoveries were 100.6% and 100.5 %, and the RSD were 0.42% and 0.58%. Conclusion: The method is simple and specific, and the result is more accurate and reliable. Which is suitable for simultaneous determination of two components in compound preparations.

Enhanced removal of phosphate from wastewater by precipitation coupled with flocculation

Eco-friendly flocculants of alginic acid, NaHCO3 and CaCl2.2H2O with advantages of strong gelation characteristics were prepared for supporting the removal of phosphate in synthetic wastewater using CaO and Ca(OH)2 as precipitants. The effects of weight ratios of each component in flocculants, dosage of flocculants and initial phosphate concentration were investigated through batch of experiments. The results showed excellent flocculation performance with the weight ratio of alginic acid:NaHCO3 and CaCl2.2H2O at 1:0.3:0.02 and the dosage of flocculants at 0.0050 g/25 mL of phosphate solution in the range of initial phosphate concentration from 50 to 1000 ppm. Comparing to the sample without flocculants, the phosphate removal efficiency using CaO and Ca(OH)2 with the addition of flocculants increased from 19 and 20% to 97% at the initial phosphate concentration of 50 ppm, respectively by filtration of filter paper 2.7 μm.

Phosphating Modification with Metal Ions of Carbon Steel Surface to Improve the Influence of Anticorrosion Properties

The purpose of this research is to investigate the influence of the phosphatizing process with Ni2+, Ce3+, and Ti2+ ions on the properties of the coating to obtain better corrosion protection of the metal. Steel corrosion occurs through physicochemical interaction between the metal and its surrounding environment. This leads to a change in the metal’s physical, mechanical, and optical properties that can cause damage to the functionality of the metal, which in turn may result in accidents or other malfunctions. Carbon steel grade has limited resistance to corrosion, depending on the carbon content and alloying element, the microstructure, and the surrounding environment of the material. This paper present tests that have been carried out on some of the physicochemical properties of protective epoxy and polyurethane coating on carbon steel grade. Coatings represent one of the methods available to protect metal surfaces from corrosion. Coating properties such as thickness, hardness, and adhesion were investigated. The same properties were tested by exposing the sample plates to corrosive conditions of the humid chamber and seawater. Their anticorrosion properties were explored by electrochemical impedance spectroscopy (EIS) techniques under immersion in 3.5 wt.% NaCl solutions as a corrosive medium. Part of the samples prior to application of the coatingwere modified with a phosphate solution containing metal ions: Ni2+, Ce3+, and Ti2+ to further investigate the effects of phosphatization on the properties of the coating. After exposure of the plates to the salt and moist chamber conditions, no traces of corrosion products, cracking or peeling of the coating were found on the surfaces. The adhesion properties were tested by the pull-off adhesion test. It was found that metal/polymer adhesion was satisfied according to EN ISO 4624:2016 and had the same value for all samples. However, a detailed EIS analysis showed a higher resistance of phosphate samples with Ce3+ ions than samples that were phosphated with Ni2+ and Ti2+ ions and those that did not have a sparingly soluble phosphate salt layer.

Transformation from calcium sulfate to calcium phosphate in biological environment

The formation of a nano-apatite surface layer is frequently considered a measure of bioactivity, especially for non-phosphate bioceramics. In the present study, strontium-doped calcium sulfate, (Ca,Sr)SO4, was used to verify the feasibility of this measure. The (Ca,Sr)SO4 specimen was prepared by mixing 10% SrSO4 by weight with 90% CaSO4·½H2O powder by weight. A solid solution of (Ca,7.6%Sr)SO4 was then produced by heating the powder mixture at 1100 °C for 1 h. The resulting (Ca,Sr)SO4 specimen was readily degradable in phosphate solution. A newly formed surface layer in the form of flakes was formed within one day of specimen immersion in phosphate solution. Structural and microstructure–compositional analyses indicated that the flakes were composed of octacalcium phosphate (OCP) crystals. An amorphous interface containing OCP nanocrystals was found between the newly formed surface layer and the remaining (Ca,Sr)SO4 specimen. The specimen was also implanted into a rat distal femur bone defect. In addition to new bone, fibrous tissue and inflammatory cells were found to interlace the (Ca,Sr)SO4 specimen. The present study indicated that a more comprehensive evaluation is needed to assess the bioactivity of non-phosphate bioceramics.

THE ENHANCED PHOTOCATALYTIC PROPERTIES OF SILVER PHOSPHATE SYNTHESIZED UNDER MANGOSTEEN PEEL EXTRACT SOLUTION

The synthesis of silver phosphate (Ag3PO4) photocatalyst has been widely developed for organic pollutant degradation. However, the large particle of this photocatalyst limits the photocatalytic activity. The smaller particle size of the Ag3PO4 photocatalyst was successfully prepared using the starting material of AgNO3 and Na2HPO4.12H2O under mangosteen peel extract solution. The starting materials were dissolved in mangosteen peel extract solutions prepared at the concentration of 1% (w/v). The reaction of silver nitrate and phosphate solution was conducted at room temperature. The samples of pristine Ag3PO4 and Ag3PO4 prepared under mangosteen peel extract were studied using XRD, DRS, SEM, BET, and FTIR. All photocatalytic activities were evaluated using Rhodamine B photooxidation under blue light irradiation (LED, 3 Watt). The results showed that the mangosteen peel extract significantly decreased the particle size, lowered the bandgap energy from 2.12 to 2.00 eV, and increased the crystallinity of Ag3PO4. The interaction of xanthones from mangosteen peel extract solution with silver ion might affect the growth particle of Ag3PO4, and inhibit the agglomeration leading to small particle size, more uniform distribution, high crystallinity, and low bandgap energy. These properties enhanced the photocatalytic activity up to 2.9 times higher compared to the sample without the treatment of mangosteen peel extract.

Extraction, Purification and Characterization of Transglutaminase From Some Plants

The present study aimed to Isolate trans-glutaminase EC:2.3.2.13 from some plants sources and Purified it and Studied it’s Charctarestics as well as it’s practical applications in the production of sausage.The enzyme was extracted from four types of plants (rosemary, chard, radish, arugula) using nine extraction solutions that included distilled water,Sodium chloride 3% solution, sodium chloride 5% solution, sodium phosphate solution 0.1 M and an pH 6.5, sodium phosphate 0.1 M and an pH of 7.5, Tris - Hcl solution 0.2 M and pH 7, Tris - Hcl solution 0.2 M and an pH 8, Tris - Hcl solution 0.1 M and an pH 7 and Tris - Hcl solution 0.1 M and an pH 8 in order to find out the best source of enzyme and the best extraction solution. chard was the best source of enzyme compared with other sources, Tirs -HCl 0.1M, pH 8 solution was the best extraction solution which gave the highest specific activity 8.104 unit/mg.Protein content for the crude enzyme extracts were concentrated using saturated ammonium sulfate in arrange 20-60%, Dialysis was done using distilled water. Then, the purification steps of the enzyme were completed using the gel filtration in the Sephadex G-100 Purification Folds 13.91 time and the yield was 20.04% %. Electrophoresise process using poly acryl amid gel in the absence of SDS observe the presence of one protein band which indicates the complete purification of transglutaminase. transglutaminase molecular weight was 42,660 Dalton when it was evaluated using poly acryl amide electrophoresis in the presence of SDS. the optimum pH for enzyme activity and enzyme stability was 7, while the optimum temperature for enzyme activity was 55°C, and the optimum temperature for enzyme stability was between 25-45°C.

Controlled self-assembly of chemical gardens enables fabrication of heterogeneous chemobrionic materials

Chemical gardens are an example of a chemobrionic system that typically result in abiotic macro-, micro- and nano- material architectures, with formation driven by complex out-of-equilibrium reaction mechanisms. From a technological perspective, controlling chemobrionic processes may hold great promise for the creation of novel, compositionally diverse and ultimately, useful materials and devices. In this work, we engineer an innovative custom-built liquid exchange unit that enables us to control the formation of tubular chemical garden structures grown from the interface between calcium loaded hydrogel and phosphate solution. We show that systematic displacement of phosphate solution with water (H2O) can halt self-assembly, precisely control tube height and purify structures in situ. Furthermore, we demonstrate the fabrication of a heterogeneous chemobrionic composite material composed of aligned, high-aspect ratio calcium phosphate channels running through an otherwise dense matrix of poly(2-hydroxyethyl methacrylate) (pHEMA). Given that the principles we derive can be broadly applied to potentially control various chemobrionic systems, this work paves the way for fabricating multifunctional materials that may hold great potential in a variety of application areas, such as regenerative medicine, catalysis and microfluidics.

Extrusion-Based 3D Printing of Calcium Magnesium Phosphate Cement Pastes for Degradable Bone Implants

This study aimed to develop printable calcium magnesium phosphate pastes that harden by immersion in ammonium phosphate solution post-printing. Besides the main mineral compound, biocompatible ceramic, magnesium oxide and hydroxypropylmethylcellulose (HPMC) were the crucial components. Two pastes with different powder to liquid ratios of 1.35 g/mL and 1.93 g/mL were characterized regarding their rheological properties. Here, ageing over the course of 24 h showed an increase in viscosity and extrusion force, which was attributed to structural changes in HPMC as well as the formation of magnesium hydroxide by hydration of MgO. The pastes enabled printing of porous scaffolds with good dimensional stability and enabled a setting reaction to struvite when immersed in ammonium phosphate solution. Mechanical performance under compression was approx. 8–20 MPa as a monolithic structure and 1.6–3.0 MPa for printed macroporous scaffolds, depending on parameters such as powder to liquid ratio, ageing time, strand thickness and distance.