Accelerated Coomassie Blue staining and destaining of SDS-PAGE gels with application of heat

Photodegradation of Biohazardous Dye Brilliant Blue R Using Organometallic Silver Nanoparticles Synthesized through a Green Chemistry Method

Simple Summary

In the paper, we utilize silver nanoparticles as a catalyst in the degradation of a hazardous dye. The nanoparticles are formed from the simple silver salt by using only a plant extract from a commonly occurring herb. The plant extract contains compounds that can both reduce the silver salt and subsequently cap the surface of the as-prepared particles. There are many environmental advantages to using such an approach—nanoparticles are prepared by using simple green chemistry and the catalytic degradation of dye is carried out by sunlight energy. Such a method can be used as a very cheap, green method to neutralize hazardous substances in-house.

Abstract

Nowadays, nanostructures having tremendous chemical and physical properties are gaining attention in the biomedical industry. However, when they are prepared through classical methods (physical and chemical), they are often non-biocompatible and toxic. Considering the mentioned factors, in this research, organometallic silver nanostructures (OMAgNs) have been prepared by the green chemistry method using the acetone, methanol, and methanol-hexane-based extracts of the medicinally important plant Cichorium intybus. Secondary metabolites from C. intybus can be used as an alternative to synthetic reagents at an industrial scale to manufacture biosafe and economical nanostructures with enhanced physicochemical parameters. Prepared nanostructures were characterized using SEM, XRD, FTIR, TGA, UV, and zeta potential measurement. SEM analysis revealed different shapes of OMAgNs, prepared with various extracts. XRD analysis showed the crystallinity of the nanostructures. FTIR spectroscopy helped to identify groups of compounds present in the extracts and used for the OMAgNs synthesis. Out of the three tested OMAgNs, those prepared with methanol extract were selected due to the highest obtained yield and stability (highest negative zeta potential) and were tested as a cost-efficient and active agent to photodegrade organic pollutant, Brilliant Blue R, using energy from sunlight. A decrease in UV-VIS absorbance confirmed the rapid degradation of the dye.

About the mechanism of ultrasonically induced protein capsule formation

In this paper, we propose a consistent mechanism of protein microcapsule formation upon ultrasound treatment. Aqueous suspensions of bovine serum albumin (BSA) microcapsules filled with toluene are prepared by use of high-intensity ultrasound following a reported method. Stabilization of the oil-in-water emulsion by the adsorption of the protein molecules at the interface of the emulsion droplets is accompanied by the creation of the cross-linked capsule shell due to formation of intermolecular disulfide bonds caused by highly reactive species like superoxide radicals generated sonochemically. The evidence for this mechanism, which until now remained elusive and was not proven properly, is presented based on experimental data from SDS-PAGE, Raman spectroscopy and dynamic light scattering.

A consistent mechanism of protein microcapsule formation upon ultrasound treatment is proposed. The evidence for this mechanism is based on experimental data from SDS-PAGE, Raman spectroscopy and dynamic light scattering.

Fungal Laccase Efficiently Destains Coomassie Brilliant Blue-R-250 Stained Polyacrylamide Gels

Fungal laccase-mediated destaining of Coomassie Brilliant Blue-R-250 stained polyacrylamide electrophoretic gel is very sensitive and environment friendly. Fermenting of Cerrena sp. HYB07 yields a broth with laccase activity which when supplemented with distilled water and used as a destaining solution results in a clear gel background in 2 h at 37 °C. Also, separation of the laccase enzyme for efficient functioning is not required. The method utilizes gel destaining and process of decolorizing dye simultaneously with a detection sensitivity of up to 10 ng. This technique avoids the use of hazardous organic compounds, as the destaining solution and the destain solution could be discarded easily without any further treatment.

Rapid Electrophoretic Staining and Destaining of Polyacrylamide Gels

Coomassie brilliant blue (CBB) dyes have been commonly used for the staining of protein bands in polyacrylamide gel electrophoresis (PAGE) gels. However, the staining and destaining of CBB dyes are time-consuming, and the use of methanol is hazardous to one's health. I introduce a rapid electrophoretic destaining method using a semi-dry transfer unit and a high current power supply. In this method, ethanol was used instead of the hazardous methanol. Most of the protein bands became visible in 30 min. After a secondary destaining step, residual CBB was completely destained. The detection limit for a tested protein (5 ng) was higher than that of the conventional method. Therefore, this method is superior in its speed, safety, low cost, and sensitivity.

Stained Gels Can Be Stored for Several Months in Nonsealed Polyethylene Bags

It is customary to dry gels (SDS-PAGE, native gels, or two-dimensional gels) after staining for record keeping purposes. This is typically carried out with gel dryers or by drying between two cellophane sheets held together by acrylic frames. Here, we report a simple method to store a variety of stained gels without any storage buffer within flexible nonsealed polyethylene bags. Gels can be stored for several months at room temperature without significant shrinking or protein diffusion. The gel stays hydrated owing to the de facto sealing achieved by the polyethylene sheets adhering air-tightly to the gel on either side. The microsaturated environment generated by the thin film of water molecules trapped between the gel and the polyethylene sheets, combined with the nonporous nature of the polyethylene sheets, apparently keeps the gel from cracking or shrinking significantly. The intensity of stained proteins increased during storage probably from the slight gel shrinkage observed. Storing gels in this manner is convenient (a) when low abundance protein spots from multiple two-dimensional electrophoresis gels have to be excised for in-gel tryptic digestion or electroelution and (b) for wet gel autoradiography. In addition to avoiding dryer contamination and saving drying time, these bags prevent the moist gel from sticking to X-ray film. Such storage could also prove useful for electrophoretic transfer of fixed and stained gels.

A streamlined Western blot exercise: An efficient and greener approach in the laboratory classroom

SDS-PAGE and western blotting are two commonly taught protein detection techniques in biochemistry and molecular biology laboratory classrooms. A pitfall associated with incorporating these techniques into the laboratory is the significant wait times that do not allow students to obtain timely results. The waiting associated with SDS-PAGE comes from staining and destaining, whereas with western blotting it is the times required for antibody incubations and the numerous wash steps. This laboratory exercise incorporates 2,2,2-trichloroethanol (TCE) into the SDS-PAGE gel allowing for visualization of migrated proteins in a matter of minutes, saving both the time and chemical waste associated with traditional Coomassie staining. Additionally, TCE staining does not affect protein transfer eliminating the requirement for duplicated gels for total protein and western analyses. Protein transfer can be confirmed immediately without the use of Ponceau S staining. Lastly, this western blot procedure has been further shortened by using an HRP-conjugated primary antibody, which eliminates the secondary antibody incubation and washes, and uses a colorimetric detection to allow for visualization by students without the need for specialized equipment.