A Comprehensive Comparison of Rapid RNA Extraction Methods for Detection of SARS-CoV-2 as the Infectious Agent of the Upper Respiratory Tract using Direct RT-LAMP Assay

Background

The current COVID-19 pandemic has highlighted the need for faster and more cost-effective diagnostic methods. The RNA extraction step in current diagnostic methods, such as real-time qPCR, increases the cost and time required for testing. Reverse-transcription loop-mediated isothermal amplification (RT-LAMP) is a promising technique for developing diagnostic tests with desired sensitivity and specificity without the need for RNA extraction.

Materials and Methods

An RT-LAMP assay was developed to detect SARS-CoV-2 with a sensitivity of 0.5 copies of positive control plasmid per microliter in 40 min. Several rapid RNA extraction protocols were evaluated using different reagents, including bovine serum albumin, Triton X-100, Tween 20, proteinase K, guanidine hydrochloride, guanidinium isothiocyanate (GITC), and thermal treatment. Finally, the sensitivity and specificity of the developed direct RT-LAMP were determined using 150 upper respiratory tract samples.

Results

Method 10 was selected as the most efficient protocol for the RNA extraction step. The sensitivity and specificity of the developed direct RT-LAMP assay with clinical samples were estimated at 98.4% and 88.8%, respectively.

Conclusion

These results suggest that the combination of GITC and Triton X-100 detergent is a highly efficient method for RNA extraction and direct RT-LAMP detection of SARS-CoV-2 in clinical samples, providing a valuable tool for the rapid and cost-effective diagnosis of COVID-19.

Nona-Arginine Mediated Anti-E6 ShRNA Delivery Suppresses the Growth of Hela Cells in vitro

Background

The E6 oncoprotein of HPV plays a crucial role in promoting cell proliferation and inhibiting apoptosis, leading to tumor growth. Non-viral vectors such as nona-arginine (R9) peptides have shown to be potential as carriers for therapeutic molecules. This study aimed to investigate the efficacy of nona-arginine in delivering E6 shRNA and suppressing the E6 gene of HeLa cells in vitro.

Methods

HeLa cells carrying E6 gene were treated with a complex of nona-arginine and E6 shRNA. The complex was evaluated using gel retardation assay and FESEM microscopy. The optimal N/P ratio for R9 peptide to transfect HeLa cells with luciferase gene was determined. Relative real-time PCR was used to evaluate the efficiency of mRNA suppression efficiency for E6 shRNA, while the effect of E6 shRNA on cell viability was measured using an MTT assay.

Results

The results indicated that R9 efficiently binds to shRNA and effectively transfects E6 shRNA complexes at N/P ratios greater than 30. Transfection with R9 and PEI complexes resulted in a significant toxicity compared to the scrambled plasmid, indicating selective toxicity for HeLa cells. Real-time PCR confirmed the reduction of E6 mRNA expression levels in the cells transfected with anti-E6 shRNA.

Conclusion

The study suggests that R9 is a promising non-viral gene carrier for transfecting E6 shRNA in vitro, with significant transfection efficiency and minimal toxicity.

Nona-Arginine Mediated Anti-E6 ShRNA Delivery Suppresses the Growth of Hela Cells in vitro

Background

The E6 oncoprotein of HPV plays a crucial role in promoting cell proliferation and inhibiting apoptosis, leading to tumor growth. Non-viral vectors such as nona-arginine (R9) peptides have shown to be potential as carriers for therapeutic molecules. This study aimed to investigate the efficacy of nona-arginine in delivering E6 shRNA and suppressing the E6 gene of HeLa cells in vitro.

Methods

HeLa cells carrying E6 gene were treated with a complex of nona-arginine and E6 shRNA. The complex was evaluated using gel retardation assay and FESEM microscopy. The optimal N/P ratio for R9 peptide to transfect HeLa cells with luciferase gene was determined. Relative real-time PCR was used to evaluate the efficiency of mRNA suppression efficiency for E6 shRNA, while the effect of E6 shRNA on cell viability was measured using an MTT assay.

Results

The results indicated that R9 efficiently binds to shRNA and effectively transfects E6 shRNA complexes at N/P ratios greater than 30. Transfection with R9 and PEI complexes resulted in a significant toxicity compared to the scrambled plasmid, indicating selective toxicity for HeLa cells. Real-time PCR confirmed the reduction of E6 mRNA expression levels in the cells transfected with anti-E6 shRNA.

Conclusion

The study suggests that R9 is a promising non-viral gene carrier for transfecting E6 shRNA in vitro, with significant transfection efficiency and minimal toxicity.

A Comparative Analysis of Different Enzyme Immobilization Nanomaterials: Progress, Constraints and Recent Trends

Immobilization techniques have been popularly used to preserve the operational stability of the enzymes for industrial applications. The three main components of an immobilized enzyme system are the enzyme, the matrix/support, and the technique of immobilization. So far, different supports have been developed to improve the efficiency of the immobilized enzymes. But in the recent decade, nanotechnology has been of considerable research interest in the field of immobilized enzyme carriers. The materials at the nano-scale, due to their unique physicochemical properties, including; specific surface area, mass transfer limitation, and effective enzyme loading, are considered interesting matrices for enzyme immobilization. This review describes techniques employed to immobilize enzymes, and provides an integrated focus on the most common nanoparticles for enzyme conjugation. Additionally, the pros and cons of nanoparticles as immobilization matrices are also discussed. Depending on the type of enzyme and its application, in this review, the researchers are directed to select an appropriate method and support for enzyme immobilization in terms of enzyme stability and functionality.