scholarly journals Reporting the limits of detection and quantification for environmental DNA assays

2019 ◽  
Vol 2 (3) ◽  
pp. 271-282 ◽  
Author(s):  
Katy E. Klymus ◽  
Christopher M. Merkes ◽  
Michael J. Allison ◽  
Caren S. Goldberg ◽  
Caren C. Helbing ◽  
...  
Keyword(s):  
Environmental Dna ◽  
Limits Of Detection ◽  
Dna Assays ◽  
Detection And Quantification

scholarly journals Effects of preservation strategies on environmental DNA detection and quantification using ddPCR

2021 ◽  
Author(s):  
Quentin Mauvisseau ◽  
David Halfmaerten ◽  
Sabrina Neyrinck ◽  
Alfred Burian ◽  
Rein Brys
Keyword(s):  
Dna Detection ◽  
Environmental Dna ◽  
Detection And Quantification

scholarly journals Quantitative Analysis of Bioactive Carbazole Alkaloids in Murraya koenigii

2015 ◽  
Vol 10 (2) ◽  
pp. 1934578X1501000
Author(s):  
Trapti Joshi ◽  
Rohit Mahar ◽  
Sumit K. Singh ◽  
Piush Srivastava ◽  
Sanjeev K. Shukla ◽  
...  
Keyword(s):  
Anticancer Agents ◽  
Uttar Pradesh ◽  
Central India ◽  
Ultra Performance Liquid Chromatography ◽  
Natural Abundance ◽  
Photodiode Array Detection ◽  
Limits Of Detection ◽  
Specific Distribution ◽  
Carbazole Alkaloids ◽  
Detection And Quantification

Carbazole alkaloids induce apoptosis in HL-60 cells through activation of the caspase-9/caspase-3 pathway and they are targeted as potential anticancer agents. Thus, the naturally occurring carbazole alkaloids become important as precursors for lead optimization in drug development. A method based on ultra performance liquid chromatography coupled with photodiode-array detection was developed using reverse phase isocratic elution with 85:15 acetonitrile and ammonium acetate buffer (5 mM). Seven samples of Murrya koenigii (L.) Spreng. from north-central India ( Uttar Pradesh) were analyzed. All three targeted analytes, koenimbidine (mk1), koenimbine (mk2) and mahanimbine (mk3), were well separated within 4.0 min with linearity of the calibration curves (r2 > 0.999). The limits of detection and quantification of mk1, mk2 and mk3 were 0.7, 0.4, 0.04 μg/mL and 2.14, 1.21, 0.12 μg/mL, respectively. The natural abundance of mk1, mk2 and mk3 was 0.06 - 0.20, 0.04 - 0.69 and 0.13 - 0.42%, w/w, respectively, in the dried powdered leaves, whereas, the tissue specific distribution of carbazole alkaloids was observed in the order of predominance, mk1 leaf>root>fruit>stem, mk2 fruit>leaf >stem>root, and mk3 fruit>leaf>root>stem. The developed method was validated for limits of detection and quantification, repeatability, accuracy, precision and stability. This is the first report on the natural abundance of the major carbazole alkaloids in M. koenigii and the method developed can be used in HPLC/UPLC systems.

scholarly journals Validation and Optimization of Ultrasound-Assisted Dispersive LiquidLiquid Microextraction as a Preparation Method for Detection of Methadone in Saliva with Gas Chromatography-Mass Spectrometry Technique

2020 ◽  
Vol 10 (2) ◽  
pp. 329-333 ◽  
Author(s):  
Ahmad Shekari ◽  
Mehdi Forouzesh ◽  
Roohollah Valipour ◽  
Fardin Fallah ◽  
Pardis Shojaei
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Preparation Method ◽  
Gas Chromatography Mass Spectrometry ◽  
Phase Volume ◽  
Limits Of Detection ◽  
Chromatography Mass Spectrometry ◽  
Ultrasound Assisted ◽  
Detection And Quantification ◽  
Extraction Phase

Purpose: We investigated validation and optimization of ultrasound-assisted dispersive liquidliquid microextraction (UADLLME) as a preparation method for detection of methadone in saliva samples. Methods: We used blank and methadone-containing saliva samples and also standard methadone solution. Sodium hydroxide and chloroform were added to samples and they were held in ultrasonic bath. Then preparations were centrifuged and extracted analyte was analyzed by gas chromatography-mass spectrometry (GC-MS). Accuracy was measured by Intra and between-day mean relative errors (RE). Precision was assessed by coefficient of variation (CV). Recovery, specificity, linearity and limits of detection and quantification were also determined. Optimization was conducted for ultrasound duration, pH and extraction phase volume. Efficiency of dispersive liquid-liquid microextraction (DLLME) and UADLLME were compared. Results: Intra and between-day accuracies (2.3 -7.5%), recovery (89.4-115.5%) and precision (5.2-11.3%) were all acceptable. Calibration curve was linear in the concentration range of 150 ng/mL-10 µL/mL with R2 >0.9995 and equation of y=86.901x-5342.5. Limits of detection and quantification were 50 and 150 ng/mL, respectively. Specificity was measured by comparing retention times of saliva samples (containing methadone metabolites and other commonly used drugs) during UADLLME/GC-MS analysis and no interference was observed. Recovery of UADLLME was 1.4 of DLLME. Solvent and sample volumes required for UADLLME were 1/200 and 1/20 of DLLME. The greatest efficiency obtained at pH of 10, with ultrasound treatment duration of 5 minutes and extraction phase volume of 1000 µL. Conclusion: Study found that UADLLME/GC-MS is a valid and efficient method for detection of methadone in oral fluid.

scholarly journals DEVELOPMENT AND VALIDATION OF AN HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR THE DETERMINATION OF 17-Β ESTRADIOL IN POLYMERIC NANOPARTICLES

2021 ◽  
pp. 112-116
Author(s):  
ADRIANA YURIKO KOGA ◽  
BRUNA CARLETTO ◽  
LEANDRO CAVALCANTE LIPINSKI ◽  
TRAUDI KLEIN ◽  
PAULO VITOR FARAGO
Keyword(s):  
Liquid Chromatography ◽  
High Performance ◽  
Polymeric Nanoparticles ◽  
Chromatography Method ◽  
Limits Of Detection ◽  
Ph Variation ◽  
Liquid Chromatography Method ◽  
The Stability ◽  
Development And Validation ◽  
Detection And Quantification

Objective: A simple high-performace liquid chromatography method was developed and validated to determine 17-β estradiol in poly (ε-caprolactone) nanocapsules. Methods: The chromatographic conditions were as follows: C18 GL column with a mobile phase of acetonitrile:water (92:8 v/v) at flow rate of 1.5 mL/min with detection at 280 nm. The evaluated parameters were specificity, linearity, limits of detection and quantification, precision, accuracy, and robustness. Results: The method was specific and linear (r=0.9982). The limits of detection and quantification were 5.78 μg.mL-1 and 17.54 μg.mL-1, respectively. Suitable accurancy and robustness were obtained. The stability assay showed that pH variation occured after 120 days of storage, and no changes were observed regarding the size and polydispersion parameters. The applicability of the method was evaluated by determining the encapsulation efficiency of the E2 nanocapsules after 120 days of storage. The results showed values >99%. Conclusion: The results demonstrated the applicability of the developed and validated analytical method.

scholarly journals Detection and quantification of Anopheles gambiae sensu lato mosquito larvae in experimental aquatic habitats using environmental DNA (eDNA).

2018 ◽  
Vol 3 ◽  
pp. 26 ◽  
Author(s):  
Joel Odero ◽  
Bruno Gomes ◽  
Ulrike Fillinger ◽  
David Weetman
Keyword(s):  
Anopheles Gambiae ◽  
Limit Of Detection ◽  
Larval Density ◽  
Indoor Residual Spraying ◽  
Environmental Dna ◽  
Malaria Vectors ◽  
Mosquito Larvae ◽  
Cyt B ◽  
Aquatic Habitats ◽  
Detection And Quantification

Background: Growing insecticide resistance and changes in biting and resting behavior of malaria vectors threaten efficacy of insecticide treated nets and indoor residual spraying. Larval source management (LSM) is a promising approach that can target mosquitoes irrespective of their behavior as adults. However, the use of traditional monitoring methods for immature stages of Anopheles mosquitoes is a major challenge to LSM due to the variability in their breeding habitats.  We evaluate the use of an environmental DNA (eDNA) analysis technique in monitoring Anopheles gambiae sensu lato larvae in experimental aquatic habitats. Methods: eDNA was simultaneously sampled and extracted from different volumes of water, number of larvae, and occupation time. Larval presence was detected using PCR and eDNA concentration in samples from 1 L habitats quantified using an IGS and cyt b TaqMan assays. The limit of detection of the two assays was tested and larval density correlated with eDNA positivity. Results: 74% of replicates in the 50 mL habitats were PCR positive with at least 6h required to get a signal from a single larva (0.02 larvae/mL). All 12 replicates where 1 L of water was used were positive with stronger PCR bands than replicates with the same larval density in 50 mL for 24 h. There was a correlation between larval densities and eDNA detection in both assays: IGS, r = 0.503, p = 0.047; and cyt b, r = 0.558, p = 0.025. There was stochasticity in eDNA detection rates, using both PCR and qPCR across all the dilutions. Conclusion: This study has demonstrated the potential use of eDNA analysis for detection and quantification of An. gambiae s.s. mosquito larvae in aquatic habitats. The stochasticity observed in eDNA detection suggest that this technique is best for monitoring aquatic habitats with many larvae at low densities.

High-Performance Liquid Chromatography Quantitative Determination of Oxyresveratrol and Morin Contained in Maclura cochinchinensis Extract and Gel Formulation

2021 ◽  
Vol 901 ◽  
pp. 79-85
Author(s):  
Arpa Petchsomrit ◽  
Boonyadist Vongsak
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
High Performance ◽  
Anticancer Activities ◽  
Limits Of Detection ◽  
Percent Recovery ◽  
Relative Standard ◽  
Traditional Drug ◽  
Detection And Quantification

Maclura cochinchinensis (Lour.) Corner., of the Moraceae family, is a medical shrub commonly found in Thailand, and for which a wide variety of pharmacological activities have been reported, including antiviral, anti-inflammatory, antioxidant, and anticancer activities. The main bioactive compounds, oxyresveratrol and morin, are known to be found in M. cochinchinensis heartwood. In this study, we quantitatively analyzed the levels of these two active substances in M. cochinchinensis extracted with various solvents, including in various cosmetic formulations and herbs sourced from various parts of Thailand. High-performance liquid chromatography (HPLC) was performed on a C18 column with an isocratic elution using 1.5% formic acid and acetonitrile at a flow rate of 1 ml/min, and detected at 352 nm. This method was validated for accuracy, precision, linearity, limits of detection, and quantification. The average percent recovery for oxyresveratrol and morin in the extracts was 100.01 ± 0.62% and 99.31 ± 2.56%, and in gel formulation was 99.65 ± 3.54% and 118.41 ± 4.70%, respectively. The relative standard deviation of intra- and inter-day precision was less than 2.0% and 2.8%, respectively. Limits of detection and quantification were 0.06 and 0.2 μg/ml, respectively. The amounts of oxyresveratrol and morin extracted from different solvents, such as acetone, 80% ethanol, 50% ethanol, methanol, and distilled water were in the range of 37.75–68.16 and 54.63–144.83 mg/g, respectively, while five samples of M. cochinchinensis heartwood collected from different regions of traditional drug stores contained in the range of 26.85–60.37 and 110.26–157.44 mg/g, respectively. Additionally, the percentage label amounts of oxyresveratrol and morin were analyzed in gel preparations, and found at 82.88% and 120.99%, respectively. This technique is convenient, simple, and reliable to effectively analyze the content of these active compounds in extracts and cosmetic products.

scholarly journals A validation scale to determine the readiness of environmental DNA assays for routine species monitoring

2021 ◽  
Author(s):  
Bettina Thalinger ◽  
Kristy Deiner ◽  
Lynsey R. Harper ◽  
Helen C. Rees ◽  
Rosetta C. Blackman ◽  
...  
Keyword(s):  
Environmental Dna ◽  
Dna Assays
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