The textile industrial chain all over the world is facing a challenge of differentiating cashmere fiber from mixture of wool and other fibers in case cashmere stocks are adulterated with wool or other fibers. For iden...The textile industrial chain all over the world is facing a challenge of differentiating cashmere fiber from mixture of wool and other fibers in case cashmere stocks are adulterated with wool or other fibers. For identification of cashmere in such mixtures, the development of microchip based real-time PCR technology offers a very sensitive, specific, and accurate solution. The technology has been validated with cashmere and wool samples procured from distant farms, and from cashmere goats and sheep of different age and sex. Model samples with incremental raw cashmere or wool content were tested. The experimentally determined content was found to be comparable to the weighed content of the respective fibers in the samples. This technology may prove a cost cutter since it needs only 1.2 μl of the PCR reagent mix. It is substantially faster than traditional real-time PCR systems for being carried as miniature reaction volume in metal microchip. These features allow faster thermal equilibrium and thermal uniformity over the entire array of microreactors. For routine tests or in commercial set up, the microchips are available as ready-to-run with lyophilized reagents in its microreactors to which only 1 μl of the 10-fold diluted isolated DNA sample is added. The lyophilized microchips offer user-friendly handling in testing laboratories and help minimize human error.展开更多
While meeting the pandemic demand of SARS-CoV-2 testing, clinical laboratories worldwide tend to adopt new test systems offering cost-effective and faster test outcomes. However, the reliability of SARS-CoV-2 test res...While meeting the pandemic demand of SARS-CoV-2 testing, clinical laboratories worldwide tend to adopt new test systems offering cost-effective and faster test outcomes. However, the reliability of SARS-CoV-2 test results has paramount importance in the management of such a health crisis. Therefore, this study sought to determine the accuracy of the test results from a novel duplex Microchip RT-PCR test system using patient saliva samples and nasal swabs stabilized in Viral Transport Medium (VTM) with reference threshold Cycle Values (Ct). The VTM used to stabilize these samples during transport was found to be inhibitory to the RT-PCR. Therefore, all the samples were subjected to spin column purification of total RNA to remove the influence of VTM. A total of 70 patient samples, including 24 positive- and 31 negative-saliva in VTM samples and 15 positive nasal swab samples, were tested. Results obtained from both the sample types were compared to their reference values and no false positive or false negatives were observed. From this data, accuracy, specificity, and sensitivity were determined to be 100% applying the corresponding formulae. The limit of detection with 95% confidence probability was determined to be 2.5 copies/μl in the original sample.展开更多
To contain the rapid and global spread of SARS-CoV-2, it is essential to develop an accurate and sensitive test system to address pandemic bottlenecks, simplified sample collection, and no sample prep. While meeting t...To contain the rapid and global spread of SARS-CoV-2, it is essential to develop an accurate and sensitive test system to address pandemic bottlenecks, simplified sample collection, and no sample prep. While meeting the demand of testing large populations, the miniaturized volume of assay reagents and offering rapid results is the need in such scenarios. Moreover, in view of the reports of co-infections and overlapping symptoms of Influenza caused by Influenza A or Influenza B, and COVID-19 caused by SARS-CoV-2, a test system with three targets can be supportive for accurate clinical diagnosis. In this presentation, we evaluated the performance of a test comprising Microchip RT-PCR Influenza and COVID-19 Detection System for identifying these three viral pathogens in nasal swabs and saliva specimens. A rapid and simplified total nucleic acid extraction method was developed and validated for the reliable, high-throughput simultaneous detection of respiratory viruses causing Influenza (type A and type B viruses) and COVID-19 (SARS-CoV-2 virus) using the microchip-based AriaDNATM platform deriving the name ABC Test. The test system was evaluated using 81 nasal swab samples, 77 clinical saliva samples, 5 blind CAP reference samples, and RNA standards. The limit of detection (LoD) was assessed using SARS-CoV-2, Influenza A, and Influenza B RNA standards. The multiplex ABC Test microchip displayed LoD of 14 copies/μL for SARS-CoV-2 and approximately 26 copies/μL for Influenza A, and 140 copies/μL for Influenza B, respectively. The ABC Test offers rapid multiplex one-step RT-PCR in 32 minutes for 45 cycles as the miniaturized reaction of 1.2 μL offering a highly sensitive, robust, and accurate assay for the detection of Influenza A/B, and SARS-CoV-2.展开更多
An RT-PCR based microchip test system for the detection of SARS-CoV-2 offers pre-loaded and lyophilized reagents in the microchip. However, the 30- and 48-microwell formats of the microchip being miniaturized and perf...An RT-PCR based microchip test system for the detection of SARS-CoV-2 offers pre-loaded and lyophilized reagents in the microchip. However, the 30- and 48-microwell formats of the microchip being miniaturized and performing 1.2 μl reaction, seek visual attention during sample addition. Therefore, adding colorants as color indicator in the lyophilized matrix in the microchips or adding to sample or master mix can impart not only user-friendliness to the task of liquid handling but also precision, and color-codes for easy identification of multiple kits in the layout of the microchip without compromising PCR data quality. A panel of colorants was screened for their background intensity, spectral inertness towards detection channels of AriaDNA<sup>TM</sup> analyzer, interference with the reporter dyes (FAM, Cy5 and ROX), and visibility of optimal concentration in the microwell. The concentration of the colorant displaying insignificant impact on the quality of the amplification (Ct, fluorescence, and sensitivity) in comparison to no-colorant control was chosen for inclusion in the test kit. Tartrazine, Acid Red, Brilliant Blue and FAST Green colorants lyophilized with the reagents in the SARS-CoV-2 microchips were found to be stable and suitable. Storage of microchips with Fast Green colorant was tested at 40°C, 22<span style="white-space:normal;">°</span>C, 4<span style="white-space:normal;">°</span>C, and -20<span style="white-space:normal;">°</span>C for 70 days and was found to be suitable and compatible with different master mixes available as liquid or lyophilized. Additionally, the microchips pre-loaded with lyophilized reagents in the presence and absence of two colorants Tartrazine and Fast Green were validated with clinical samples of SARS-COV-2. No significant impact of these colorants both intra- and inter-microchips was observed on the Ct and intensity of amplification for the tested samples in comparison to no-colorant control. The data suggested that the tested colorants can be used to color the sample, or the master mix or PCR mix for user-friendly liquid handling in empty microchips. For the microchip with pre-loaded and lyophilized reagents, the colorant can be added to lyophilized mixture for precision liquid handling and color-coding of lyophilized kits in the microchips. The manufacturing quality of the lyophilized microchips can also improve with colorant loaded reagent mix.展开更多
In addition to the conventional methods of the calibration model construction, such as PCR (principal components regression) and PLS (partial least-squares), a MPM (mathematical programming method) is developed ...In addition to the conventional methods of the calibration model construction, such as PCR (principal components regression) and PLS (partial least-squares), a MPM (mathematical programming method) is developed and proposed for practical use in NIR analyses of agricultural and food products. The proposed method involves the mathematical programming techniques to seek the regression coefficients for the calibration model calculation. It is based on the optimization theory used for finding the extremum of the objective function in the given domain of a vector space and employs the method of the complementarity problems solving. The MPM algorithm is described in detail. The MPM was tested on an InfraLUM FT-10 NIR analyzer of Lumex company with samples of dry milk (for fat), corn (for protein) and rye flour (for moisture). The obtained results show that the MPM can be used for constructing multivariate calibrations with the qualitative characteristics superior over those of the classical PCR and PLS methods of analysis.展开更多
Development of non expensive and time-saving techniques based on the polymerase chain reaction (PCR) is of great importance for modern diagnostics. We considered a new approach for PCR determination of a variety of se...Development of non expensive and time-saving techniques based on the polymerase chain reaction (PCR) is of great importance for modern diagnostics. We considered a new approach for PCR determination of a variety of sexually transmitted infections using microchip analyzer “AriaDNA”, which had been tested using clinical samples in several medical institutions of St. Petersburg (Russia). The use of microchips containing lyophilized PCR reagents allows reducing significantly time of analysis and the number of manipulations thus preventing possible sample contamination.展开更多
文摘The textile industrial chain all over the world is facing a challenge of differentiating cashmere fiber from mixture of wool and other fibers in case cashmere stocks are adulterated with wool or other fibers. For identification of cashmere in such mixtures, the development of microchip based real-time PCR technology offers a very sensitive, specific, and accurate solution. The technology has been validated with cashmere and wool samples procured from distant farms, and from cashmere goats and sheep of different age and sex. Model samples with incremental raw cashmere or wool content were tested. The experimentally determined content was found to be comparable to the weighed content of the respective fibers in the samples. This technology may prove a cost cutter since it needs only 1.2 μl of the PCR reagent mix. It is substantially faster than traditional real-time PCR systems for being carried as miniature reaction volume in metal microchip. These features allow faster thermal equilibrium and thermal uniformity over the entire array of microreactors. For routine tests or in commercial set up, the microchips are available as ready-to-run with lyophilized reagents in its microreactors to which only 1 μl of the 10-fold diluted isolated DNA sample is added. The lyophilized microchips offer user-friendly handling in testing laboratories and help minimize human error.
文摘While meeting the pandemic demand of SARS-CoV-2 testing, clinical laboratories worldwide tend to adopt new test systems offering cost-effective and faster test outcomes. However, the reliability of SARS-CoV-2 test results has paramount importance in the management of such a health crisis. Therefore, this study sought to determine the accuracy of the test results from a novel duplex Microchip RT-PCR test system using patient saliva samples and nasal swabs stabilized in Viral Transport Medium (VTM) with reference threshold Cycle Values (Ct). The VTM used to stabilize these samples during transport was found to be inhibitory to the RT-PCR. Therefore, all the samples were subjected to spin column purification of total RNA to remove the influence of VTM. A total of 70 patient samples, including 24 positive- and 31 negative-saliva in VTM samples and 15 positive nasal swab samples, were tested. Results obtained from both the sample types were compared to their reference values and no false positive or false negatives were observed. From this data, accuracy, specificity, and sensitivity were determined to be 100% applying the corresponding formulae. The limit of detection with 95% confidence probability was determined to be 2.5 copies/μl in the original sample.
文摘To contain the rapid and global spread of SARS-CoV-2, it is essential to develop an accurate and sensitive test system to address pandemic bottlenecks, simplified sample collection, and no sample prep. While meeting the demand of testing large populations, the miniaturized volume of assay reagents and offering rapid results is the need in such scenarios. Moreover, in view of the reports of co-infections and overlapping symptoms of Influenza caused by Influenza A or Influenza B, and COVID-19 caused by SARS-CoV-2, a test system with three targets can be supportive for accurate clinical diagnosis. In this presentation, we evaluated the performance of a test comprising Microchip RT-PCR Influenza and COVID-19 Detection System for identifying these three viral pathogens in nasal swabs and saliva specimens. A rapid and simplified total nucleic acid extraction method was developed and validated for the reliable, high-throughput simultaneous detection of respiratory viruses causing Influenza (type A and type B viruses) and COVID-19 (SARS-CoV-2 virus) using the microchip-based AriaDNATM platform deriving the name ABC Test. The test system was evaluated using 81 nasal swab samples, 77 clinical saliva samples, 5 blind CAP reference samples, and RNA standards. The limit of detection (LoD) was assessed using SARS-CoV-2, Influenza A, and Influenza B RNA standards. The multiplex ABC Test microchip displayed LoD of 14 copies/μL for SARS-CoV-2 and approximately 26 copies/μL for Influenza A, and 140 copies/μL for Influenza B, respectively. The ABC Test offers rapid multiplex one-step RT-PCR in 32 minutes for 45 cycles as the miniaturized reaction of 1.2 μL offering a highly sensitive, robust, and accurate assay for the detection of Influenza A/B, and SARS-CoV-2.
文摘An RT-PCR based microchip test system for the detection of SARS-CoV-2 offers pre-loaded and lyophilized reagents in the microchip. However, the 30- and 48-microwell formats of the microchip being miniaturized and performing 1.2 μl reaction, seek visual attention during sample addition. Therefore, adding colorants as color indicator in the lyophilized matrix in the microchips or adding to sample or master mix can impart not only user-friendliness to the task of liquid handling but also precision, and color-codes for easy identification of multiple kits in the layout of the microchip without compromising PCR data quality. A panel of colorants was screened for their background intensity, spectral inertness towards detection channels of AriaDNA<sup>TM</sup> analyzer, interference with the reporter dyes (FAM, Cy5 and ROX), and visibility of optimal concentration in the microwell. The concentration of the colorant displaying insignificant impact on the quality of the amplification (Ct, fluorescence, and sensitivity) in comparison to no-colorant control was chosen for inclusion in the test kit. Tartrazine, Acid Red, Brilliant Blue and FAST Green colorants lyophilized with the reagents in the SARS-CoV-2 microchips were found to be stable and suitable. Storage of microchips with Fast Green colorant was tested at 40°C, 22<span style="white-space:normal;">°</span>C, 4<span style="white-space:normal;">°</span>C, and -20<span style="white-space:normal;">°</span>C for 70 days and was found to be suitable and compatible with different master mixes available as liquid or lyophilized. Additionally, the microchips pre-loaded with lyophilized reagents in the presence and absence of two colorants Tartrazine and Fast Green were validated with clinical samples of SARS-COV-2. No significant impact of these colorants both intra- and inter-microchips was observed on the Ct and intensity of amplification for the tested samples in comparison to no-colorant control. The data suggested that the tested colorants can be used to color the sample, or the master mix or PCR mix for user-friendly liquid handling in empty microchips. For the microchip with pre-loaded and lyophilized reagents, the colorant can be added to lyophilized mixture for precision liquid handling and color-coding of lyophilized kits in the microchips. The manufacturing quality of the lyophilized microchips can also improve with colorant loaded reagent mix.
文摘In addition to the conventional methods of the calibration model construction, such as PCR (principal components regression) and PLS (partial least-squares), a MPM (mathematical programming method) is developed and proposed for practical use in NIR analyses of agricultural and food products. The proposed method involves the mathematical programming techniques to seek the regression coefficients for the calibration model calculation. It is based on the optimization theory used for finding the extremum of the objective function in the given domain of a vector space and employs the method of the complementarity problems solving. The MPM algorithm is described in detail. The MPM was tested on an InfraLUM FT-10 NIR analyzer of Lumex company with samples of dry milk (for fat), corn (for protein) and rye flour (for moisture). The obtained results show that the MPM can be used for constructing multivariate calibrations with the qualitative characteristics superior over those of the classical PCR and PLS methods of analysis.
文摘Development of non expensive and time-saving techniques based on the polymerase chain reaction (PCR) is of great importance for modern diagnostics. We considered a new approach for PCR determination of a variety of sexually transmitted infections using microchip analyzer “AriaDNA”, which had been tested using clinical samples in several medical institutions of St. Petersburg (Russia). The use of microchips containing lyophilized PCR reagents allows reducing significantly time of analysis and the number of manipulations thus preventing possible sample contamination.