Biocompatibility and cytotoxicity in vitro of surface-functionalized drug-loaded spinel ferrite nanoparticles

In this study, poly(isobutylene-alt-maleic anhydride) (PMA)-coated spinel ferrite (MFe2O4, where M = Fe, Co, Ni, or Zn) nanoparticles (NPs) were developed as carriers of the anticancer drugs doxorubicin (DOX) and methotrexate (MTX). Physical characterizations confirmed the formation of pure cubic structures (14–22 nm) with magnetic properties. Drug-loaded NPs exhibited tumor specificity with significantly higher (p < 0.005) drug release in an acidic environment (pH 5.5). The nanoparticles were highly colloidal (zeta potential = −35 to −26 mV) in deionized water, phosphate buffer saline (PBS), and sodium borate buffer (SBB). They showed elevated and dose-dependent cytotoxicity in vitro compared to free drug controls. The IC50 values ranged from 0.81 to 3.97 μg/mL for HepG2 and HT144 cells, whereas IC50 values for normal lymphocytes were 10 to 35 times higher (18.35–43.04 µg/mL). Cobalt ferrite (CFO) and zinc ferrite (ZFO) NPs were highly genotoxic (p < 0.05) in cancer cell lines. The nanoparticles caused cytotoxicity via oxidative stress, causing DNA damage and activation of p53-mediated cell cycle arrest (significantly elevated expression, p < 0.005, majorly G1 and G2/M arrest) and apoptosis. Cytotoxicity testing in 3D spheroids showed significant (p < 0.05) reduction in spheroid diameter and up to 74 ± 8.9% of cell death after two weeks. In addition, they also inhibited multidrug resistance (MDR) pump activity in both cell lines suggesting effectivity in MDR cancers. Among the tested MFe2O4 NPs, CFO nanocarriers were the most favorable for targeted cancer therapy due to excellent magnetic, colloidal, cytotoxic, and biocompatible aspects. However, detailed mechanistic, in vivo cytotoxicity, and magnetic-field-assisted studies are required to fully exploit these nanocarriers in therapeutic applications.

Assessment of corn starch as substitute for agarose in DNA gel electrophoresis

Objective The use of agarose in nucleic acid electrophoresis is the gold standard. However, agarose is very expensive and not readily available in resource limited developing countries like Ghana. Hence, finding a more affordable and readily available alternative to agarose will be a major boost to molecular research in developing countries. This study was aimed at investigating the use of corn starch as a potential substitute for agarose in DNA gel electrophoresis. Results Genomic deoxyribonucleic acid (DNA) extracted from Plasmodium falciparum and primers were obtained from the West African Centre for Cell Biology of Infectious Pathogens and amplified using polymerase chain reaction. The amplicon was run on agarose gel to ascertain the molecular weight (as a positive control). When visualized under both blue light and ultraviolet light, the DNA and ladder showed clear and clean bands with the expected molecular weight. Corn starch was then modified with sodium borate buffer, casted into a gel and used to run the same DNA sample. Our findings indicated that similar to agarose, the DNA sample and ladder migrated successfully through the modified starch gel but no bands were visible when visualized under blue and ultra-violet light.

Assessment of Corn Starch as Substitute for Agarose in DNA Gel Electrophoresis

ObjectiveThe use of agarose in nucleic acid electrophoresis is the gold standard. However, agarose is very expensive and not readily available in resource limited developing countries like Ghana. Hence, finding a more affordable and readily available alternative to agarose will be a major boost to molecular research in developing countries. This study was aimed at investigating the use of corn starch as a potential substitute for agarose in DNA gel electrophoresis.ResultsGenomic DNA extracted from Plasmodium falciparum and primers were obtained from the West African Centre for Cell Biology of Infectious Pathogens and amplified using polymerase chain reaction. The amplicon was run on agarose gel to ascertain the molecular weight (as a positive control). When visualized under both blue light and ultraviolet light, the DNA and ladder showed clear and clean bands with the expected molecular weight. Corn starch was then modified with sodium borate buffer, casted into a gel and used to run the same DNA sample. Our findings indicated that similar to agarose, the DNA sample and ladder migrated successfully through the modified starch gel but no bands were visible when visualized under blue and ultra-violet light.

Fibrinolytic Activity of Two Polypeptide Chains from Human Plasminogen#

Background: Plasminogen is a blood plasma glycoprotein of molecular weight about 92,000 Daltons. Physiologically, it incorporates into blood clots and after its activation by plasminogen activators to plasmin can perform a fibrinolytic function. Microplasmin is truncate polypeptide chain derivate of plasmin may be increase the fibrinolytic activity. Objective: To study the amino acid sequence of two polypeptides chains derivate to the plasminogen with fibrinolytic activity. Methods: he two polypeptides chains were prepared by isoelectric precipitation of human plasma in sodium borate buffer. The sample in a second step was subjected to affinity and ionic interchange chromatography and denaturalized electrophoresis was carried out on the sample previous heat 70ºC. Results: Two polypeptide chains of 29.000 and 35.000 Daltons by autolysis controlled were obtained with 25 UI of fibrinolytic activity in fibrin plate. Conclusion: Microplasmin was obtained with cleavage in different amino acid bounds and rearrangement of amino acids by autolysis with controlled alkaline precipitation.

Synthesis of InP/ZnS Nanocrystals and Phase Transfer by Hydrolysis of Ester

The synthesis of highly luminescent non-toxic nanocrystals (NCs) and the subsequent phase transfer to aqueous solution by hydrolysis of the crystal-bound ester are presented. Therefore, the synthesis of the spherical semiconductor system InP/ZnS was modified by changing the sulfur precursor in the synthesis from 1-dodecanethiol to dodecyl 3-mercaptopropionate (D3MP). By employing D3MP both as sulfur precursor for the ZnS shell growth and as stabilizing ligand, the phase transfer from organic to aqueous solution can be performed easily. Instead of the usually employed ligand exchange with mercaptopropionic acid, the NCs are only shaken with a sodium borate buffer in order to obtain aqueous soluble NCs by hydrolysis of the ester. In future work, the NCs must be protected against aggregation and the long term stability has to be increased. The optical properties of the samples are investigated by UV/Vis and photoluminescence spectroscopy, and the morphology of the nanoparticles (NPs) before and after phase transfer is determined by transmission electron microscopy.

Detection and Assay of Vitamin B-2 (Riboflavin) in Alkaline Borate Buffer with UV/Visible Spectrophotometry

The detection and assay of vitamin B-2 (riboflavin) was accomplished under aqueous conditions using sodium borate buffering at pH 7.52 conditions. The absorbance spectrum of riboflavin was determined at different pH values utilizing several buffers. The buffer at pH at 7.52 is followed by accurate and sensitive assay of riboflavin by spectrophotometer at 440 nm wavelength. Where indicated an origin solution (stock) was employed by dissolving sufficient vitamin to make a stock solution of 1.403×10-4 molar concentrations. Measurements of various aqueous solutions containing riboflavin were accomplished that included aqueous test samples, vitamin capsules/tablets, and water vitamin mixtures. A standard curve extended from 7.97×10-7 molar to 1.23×10-4 molar (a 154x folds spread in concentration). The equation of the line was y = 12545x (intercept at origin) with Pearson r correlation of 1.000 (R2=1.000). Concentration of riboflavin assayed ranged from 3.00×10-4 gram per liter (0.30 ppm) to 0.0463 gram per liter (46.35 ppm). The B vitamin riboflavin can be assayed by UV/VIS spectrophotometer at 440 nm in aqueous media and using sodium borate buffer at pH 7.52. The assay can reach as low as 0.30 parts per million with high levels of accuracy and sensitivity.

Determination of Trace Cobalt in Water by Microwave Digestion-Catalytic Fading Spectrophotometry

A simple and sensitive catalytic fading spectrophometry was developted for determination the trace cobalt in water treated by microwave digestion. The method is based on catalysis of cobalt on the oxidation of acid chrome blue K by potassium periodate with polyethylene glycol-200 as an activator in boric acid-sodium borate buffer solution. Major factors such as microwave digestion conditions, kinds and dosages of media, reagents and activators, the reaction temperature, the reaction time and coexisting irons were investigated and the optimal experimental conditions are determination wavelength 525 nm, at 80°C reacton for 12 min. The linear range and the detection limit of the method are determinated.The maximum relative standard deviation is 5.68 %, and the recoveries are 96.4 % to 105.9 %. The maximum relative error compared with GB( national standard of china 3838-2002) is below 5.52 %.

STEROID FOCUSING BY MICELLE COLLAPSE IN MICELLAR ELECTROKINETIC CHROMATOGRAPHY

Preliminary studies on the separation of neutral steroids through analyte focusing by micelle collapse (AFMC) are presented to investigate its efficiency, sensitivity and limit of detection (LOD). The focusing mechanism of AFMC is based on the transport, release, and accumulation of molecules bound to micelle carriers that are made to collapse into a liquid phase zone. The sample solution of the neutral analytes (S) is prepared using sodium dodecyl sulphate (SDS) at a concentration above the critical micelle concentration (cmc) with higher conductivity than the running buffer. Normal mode–micellar electrokinetic chromatography (NM–MEKC) separation was initially performed on 100 mg/L of six neutral steroids in methanol using 20 mM SDS, 10% (v/v) methanol and sodium borate buffer (pH 9.0) with positive applied voltage of 25 kV and pressure injection of 50 mbar for 1 sec at 25°C. The same buffer condition has been applied to AFMC–MEKC, whereby the mixture of six neutral steroids was dissolved in 2 mM SDS and 250 mM sodium borate buffer which gave a conductivity ratio of 0.49. Results showed a good separation of prednisolone, prednisone, betamethasone, testosterone, 17–α–methyltestosterone, and 4–androstene–3,17–dione at 240 nm with sensitivity enhancement factors of 2.08, 1.17, 0.92, 16.9, 0.8, and 1.21 respectively. AFMC–MEKC allowed several folds improvement in sensitivity compared to NM–MEKC.

Isolation and purification of microbial community DNA from soil naturally enriched for chitin

We made an attempt to isolate and purify metagenomic DNA from chitin enriched soil. In this communication we report a modified direct lysis method for soil DNA extraction including initial pre-lysis washing of sample, followed by a rapid polyvinylpyrrolidone-agarose-based purification and electroelution of DNA using Gene-capsule™ assembly. Rapidity was achieved using low molarity conducting media (sodium-borate buffer) for electrophoresis by reducing run time for both the gel electrophoresis and electroelution. Extracted DNA was sufficiently pure and of high quality, evidenced by amplification of 16S rDNA and chitinase genes by PCR. Metagenomic nature of the DNA was confirmed by running V3 (16S rDNA) region amplicons using denaturing gradient gel electrophoresis. This method requires 30 min for purification, and less than 2 h for complete execution of protocol and becomes the first report on the isolation of metagenomic DNA from soil naturally enriched for chitin.

High Flow Rate Per Power Pumping of Aqueous Solutions and Organic Solvents With Electroosmotic Pumps

We present experimental investigations of porous glass electroosmotic pumping of various low conductivity solutions. We evaluate pump pressure, flow rate, and current for sodium borate buffer, deionized water, deuterium oxide, methanol, and acetone. We present data for several figures of merit associated with steady state pumping, and present selected transient data measurements.