Enhanced Resolution of DNA Separation Using Agarose Gel Electrophoresis Doped with Graphene Oxide

Potential of carbohydrate-conjugated graphene assemblies in biomedical applications

Graphene displays various properties like optical, electrical, mechanical, etc. resulting in a large range of applications in biosensing, bio-imaging, medical and electronic devices. The graphene-based nanomaterials show disadvantages like hydrophobic surface, degradation of biomolecules (proteins and amino acids) and toxicity to the human and microbes by permeating into the cells and thus, limiting the use in the biomedical field. Conjugation of carbohydrates like chitin, cyclodextrins and cellulose with graphene results in thermal stability, oxygen repulsive ability, fire-retardant and gelling properties with better biodegradability, biocompatibility and safety leading to the formation of environment-friendly biopolymers. This article delivers an overview of the molecular interaction of different carbohydrates-derived from natural sources like marine, plants and microbes with graphene nanosheets to extend the applications in tissue engineering, surgical materials, biosensing and novel drug delivery for prolonged action in the treatment of breast and hepatic cancers.

Multi-Snapshot Imaging for Chromatographic Peak Analysis

OBJECTIVE

Snapshot imaging has several advantages in automated gel electrophoresis compared with the finish-line method in capillary electrophoresis; this comes at the expense of resolution. A novel signal processing algorithm is proposed enabling a multisnapshot imaging (MSI) modality whose objective is to substantially improve resolution. MSI takes multiple-captures in time as macromolecules are electrophoresed. Peaks from latter snapshots have high resolution, but low signal-to-noise ratio (SNR), while earlier snapshots have low resolution, but high SNR.

METHODS

Signals at different capture-times are related by a scale-in-separation, shift-in-separation, and amplitude gain. The proposed method realigns the multiple captures using least-squares and fuses them. The algorithm accounts for the partial waveforms observed as the chromatic peaks exit the sensor's field-of-view.

RESULTS

MSI improves resolution by approximately [Formula: see text] on average per minute of additional electrophoresis.

CONCLUSIONS

Comprehensive analysis of the resolution quantified on several data sets demonstrates the effectiveness of MSI.

SIGNIFICANCE

MSI can double the resolution compared with traditional snap-shot imaging over a typical set of captures.

Functionalized Nano-adsorbent for Affinity Separation of Proteins

Thiol-functionalized silica nanospheres (SiO₂-SH NSs) with an average diameter of 460 nm were synthesized through a hydrothermal route. Subsequently, the prepared SiO₂-SH NSs were modified by SnO₂ quantum dots to afford SnO₂/SiO₂ composite NSs possessing obvious fluorescence, which could be used to trace the target protein. The SnO₂/SiO₂ NSs were further modified by reduced glutathione (GSH) to obtain SnO₂/SiO₂-GSH NSs, which can specifically separate glutathione S-transferase-tagged (GST-tagged) protein. Moreover, the peroxidase activity of glutathione peroxidase 3 (GPX3) separated from SnO₂/SiO₂-GSH NSs in vitro was evaluated. Results show that the prepared SnO₂/SiO₂-GSH NSs exhibit negligible nonspecific adsorption, high concentration of protein binding (7.4 mg/g), and good reused properties. In the meantime, the GST-tagged GPX3 separated by these NSs can retain its redox state and peroxidase activity. Therefore, the prepared SnO₂/SiO₂-GSH NSs might find promising application in the rapid separation and purification of GST-tagged proteins.