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Goli, S.

Publications and source records attributed to Goli, S..

2 recordsLinked to original sources

A novel approach for the extraction of nucleic acids using a hybrid paper-plastic device

Nucleic acid-based diagnostics play a crucial role in early and accurate disease detection. However, conventional extraction approaches are expensive, time-consuming, and require complex instrumentation and skilled personnel, which restricts their use in resource-limited settings. To develop and evaluate a simple, low-cost, and equipment-free paper-based microfluidic cassette device for rapid extraction of nucleic acids (DNA and RNA) from biological samples. A paper-plastic cassette was fabricated by laminating filter paper or glass fiber substrates between thermally bonded plastic sheets. The system was tested using Klebsiella pneumoniae (DNA) and HeLa cells (RNA) with different lysis buffer formulations. Extracted nucleic acids were quantified using a Qubit fluorimeter and assessed by gel electrophoresis and PCR amplification. Results were compared with standard commercial extraction kits. Among tested substrates, LF1 combined with lysis buffers 2, 4, and 5 yielded the highest quality DNA and RNA with 260/280 absorbance ratios of approximately 1.8 (DNA) and 2.0 (RNA). The nucleic acid yields were comparable to commercial kits, and the extracted material was suitable for direct downstream applications, including PCR. The developed paper-plastic cassette enables rapid, affordable, and equipment-free extraction of nucleic acids. This platform shows strong potential for point-of-care molecular diagnostics, particularly in low-resource and decentralized healthcare settings.

molecular biology↗

Generation of uniform-sized spheroids using PDMS-based microwell devices as 3D cancer models for pharmacological profiling of drugs

Cancer researchers now consider spheroids a valuable in vitro model for cancer research and personalized medicine. They are used to studying cancer development, testing drug effectiveness, and potentially guiding treatment decisions for individual patients. Spheroids represent the simplest form of three-dimensional (3D) cellular arrangement and encapsulate the essential tumor microenvironment. These characteristics are crucial for studying processes such as tumor invasion, metastasis, angiogenesis, and cell cycle kinetics. In particular, spheroids excel in chemo-response assays where traditional monolayer cell cultures often fall short. A PDMS microwell device was developed to generate uniform-sized cancer spheroids. This device is user-friendly and capable of producing a large number of spheroids. The device measures 13 mm in diameter (1200 microwells per well if the device has microwells 400 m in size, and 300 microwells per well if the device has microwells 800 m in size). It advances 3D cultures by requiring only a small volume of cell culture supplements and is easy to manage. The hydrophobic nature of the PDMS device prevents cells from adhering to it, thereby promoting spheroid formation. Spheroids can be created on microwell devices, and subsequent experiments may either be conducted on the device or transferred to cell culture dishes for additional 3D biological assays. Seeding cells is notably easier compared to other 3D cell culture techniques, and the number of cells in each spheroid can be adjusted according to specific requirements. Overall, the PDMS-based microwell device offers a simple and efficient means to produce large quantities of uniform-sized spheroids for 3D cell culture studies, showcasing high throughput, short generation times, long-term effectiveness, and ease of handling.

bioengineering↗