Standard Method For Determination Research Articles

Analysis of Pollutants for the Sustainable Reuse of Waste Lubricant Oils

Nowadays, attention to the environment is increasingly emphasized by the scientific community. Different measures have been adopted to ensure a lower environmental impact and increase the sustainability of industrial processes. This work fits well with these principles, as it focuses on the determination of pollutants in waste lubricating oils derived from the industrial and automotive sectors to quantify their concentration for potential recovery and subsequent reuse. Modern waste oils, especially those derived from industrial processes, contain pollutants and metals (most importantly, silicon). It is of utmost importance to determine the silicon content in the collected waste oils to verify the possibility of recycling them since high concentrations can badly affect the industrial operations in which they can be involved. One of the most applied analytic methods for controlling the content of metals is the ASTM D5185-18, Standard Test Method for Multielement Determination of Used and Unused Lubricating Oils and Base Oils by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES). However, this method was certified for 50 mg/kg of maximum silicon content. To extend this range, CONOU, because of its duty to monitor waste oil quality, organized an interlaboratory comparison to verify the applicability of ASTM D5185-18 and also to samples of used oils containing higher concentrations of silicon. This work describes the details of the employed methodology and the results of the interlaboratory comparison that showed the applicability of ASTM D5185-18 also to samples containing silicon concentrations higher than 1000 ppm.

Assessing the impact of various tuberculin PPD brands on bovine tuberculosis diagnosis

Although several brands of tuberculin purified protein derivatives (PPDs) are available for diagnosing bovine tuberculosis (bTB), comparative studies to determine their diagnostic accuracy are infrequent. In Ecuador we compared two different PPD brands for bTB diagnosis using skin testing and measuring skin thickness increase. Additionally, we evaluated four PPD brands, including those used for skin testing, in the Bovine Tuberculosis Interferon Gamma Test (IFN-γ test) measuring IFN-γ induction in whole blood. The study included 17 naturally tuberculosis-infected PPD and IFN-γ test positive bovines. Both the field and laboratory results showed significant differences in classifying the 17 bovines as bTB positive or negative. We hypothesize that several factors, such as the genetic background of the cows, sensitization to environmental mycobacteria, M. bovis strains involved in the bTB infection, and the manufacturing procedures of the PPDs, could have influenced the immune reaction toward the different tuberculin PPD brands. Our study emphasizes the necessity for comparative studies aimed at determining the diagnostic accuracy of PPD brands for bTB diagnosis as well as the development of standardized methods for PPD production and potency determination.

A new manual method for pork belly firmness measurement

A new objective and standardized method for early determination of firmness of the intact pork belly in a research environment is described, and compared to the existing bar-bend method. The belly characteristics that contribute to the outcome of each method, and the relationship between the two methods are identified.•Original method requires a ribbed pork belly, and several minutes relaxation time.•New method provides an immediate measurement on an intact belly.•Advantages include early, rather than late, application in the fabrication process; rapid measurement; standardization; measurements minimally affected by animal length or belly length.

Risk Assessment of Drinkable Water from Hand-dug Reservoirs Using Gross Alpha and Beta Radioactivity Levels in Ogwashi-Uku, Delta State

Over the past decade, radioactivity in drinking water has become a matter of urgent concern following reports from various scientific researches. The rapid urbanization and increase in population of Ogwashi-Uku has culminated in the increase for demand of safe and potable water hence the need for this study. A total of 10 samples were collected from the study location. Standard methods for determination of gross alpha and gross beta activity concentrations in the water samples were deployed. The measured gross alpha activity concentrations for all water samples are below 0.1 Bq/L while the measured gross beta activity concentrations in all water samples collected are lower than 1.0 Bq/L permissible limit. The mean annual dose equivalent in all the water samples for gross alpha and gross beta activity is lower than 0.1 mSv recommended dose for radionuclides in water, hence the life cancer risk assessment showed lower values, indicating the water is safe for drinking. The purpose of this study is to assess the concentration of gross alpha and beta activity levels of drinking water from hand-dug reservoirs in Ogwashi-Uku, Delta State in order to offer a scientific basis for making decisions regarding mitigating radioactive pollution and also to ensure the safety of drinking water and public health.

Nutritional content of Ficus benjamina fruits consumed by Frugivorous birds in Taman Botani Johor

Ficus benjamina is a common tree in Taman Botani Johor and a food source for many frugivorous birds. This study investigated the nutrient content of F. benjamina fruits by analyzing the fruits of 7 species of birds that were observed safely feeding on the tree. The fruits were collected and analyzed for their nutrient content using a standard method for nutritional composition determination. The results showed that the fruits have a high carbohydrate content (19.7%), a low fat content (0.6%), and a moderate protein content (1.5%). The fruits also have a high moisture content (76.7%) and a low ash content (1.6%). The high carbohydrate content of fruits is likely attractive to frugivorous birds, as carbohydrates are an important energy source for reproduction, growth, and development. The low-fat content may also be beneficial to the birds, as excess fat can be harmful to their health. The results of this study provide valuable information on the nutrient content of F. benjamina fruits, which can be used to better understand the feeding ecology of frugivorous birds in Taman Botani Johor in a safe manner.

Identification of an optimal method for echocardiographic right ventricular mass estimation in a swine model of pulmonary hypertension

Abstract Background Right ventricular (RV) mass and Fulton Index (FI) - the ratio of right to left ventricular mass - are useful markers of RV remodeling and predictors of mortality in pulmonary hypertension (PH). Cardiac magnetic resonance imaging provides an accurate estimation of RV mass but cost, availability and patient contraindications limit broad application. While echocardiography is universally available and offers feasible longitudinal assessments, current guidelines lack a standardized method for RV mass determination. Purpose We compared the performance of four previously described echocardiographic models of RV mass to estimate actual RV weight and FI measured post-mortem in a swine model of PH. Methods Echocardiography was performed in a Yorkshire pig model of post-capillary PH induced by pulmonary vein banding and healthy animals using a Philips iE-33 ultrasound system (n=70). RV mass was measured using the following models: trapezoid method (1), exact radius method (2), longitudinal plane method (3), and an algorithm (4) proposed by Kochav's group. Figure 1 depicts pertinent echocardiographic views and parameters. A two-dimensional area-length method was applied to estimate left ventricular mass and FI was calculated. On the day of echocardiography, pigs were euthanized, hearts were explanted, and ventricular weights were recorded. Pearson’s correlation, linear regression and Bland-Altman analysis were employed to evaluate different methods compared to recorded weights and Fulton Index. Results PH animals presented with significant RV remodeling and higher RV weights (42.4g, range 18.4-93.6g) compared to control pigs (30.5g, range 11.1-46.0g), allowing for examination of echocardiographic methods across a wide span of RV weights. FI ranged from 0.29 to 3.60 with a mean of 0.70. All methods demonstrated a strong linear relationship with post-mortem RV weight (r(1) = 0.88, r(2) = 0.88, r(3) = 0.84 r(4) = 0.82, p<0.0001). Bland-Altmann analysis revealed good agreement with recorded RV mass for trapezoid, exact radius and longitudinal plane method (bias(1) = 4.5±7.5g, bias(2) = -5.9±6.6g, bias(3) = -2.7±8.4g) while Kochav’s algorithm tended to underestimate RV weights (bias(4) = -18.5±8.7g). Figure 2 illustrates the performance of exact radius and longitudinal plane methods. Measured left ventricular mass correlated strongly with post-mortem left ventricular weight and reached good agreement (r = 0.91, p<0.0001; bias = -4.0±9.8g). FI was best approximated by exact radius (bias = -0.04±0.12) and longitudinal plane (bias = 0.01±0.18) methods. The trapezoid model tended to overestimate FI (bias = 0.10±0.11) and Kochav’s algorithm underestimated (bias = -0.23±0.12). Conclusion RV mass and FI can be successfully approximated using echocardiography in a clinically relevant porcine PH model. Longitudinal plane and exact radius methods performed best and can be suggested for evaluating RV mass in clinical PH patients.Figure 1Figure 2

A simple and rapid external standard calibration HPLC method for determination of lumefantrine in dried blood spot samples from malaria patients in Botswana.

A simple external calibration liquid chromatography-diode array detector method was developed, validated, and applied for the determination of lumefantrine (Lum) in dried blood spot (DBS) samples collected from malaria patients in Botswana. The samples were validated in accordance with the United States Food and Drug Administration guidelines for bioanalytical methods after sample preparation using solid-liquid extraction. Separation was achieved using an XTerra C18 column (50 × 4.6mm,5μm), and a binary solvent system of acetonitrile and water adjusted to pH2.3 was used as the mobile phase. The validated method was applied for the determination of Lum in DBS samples collected from malaria patients infected with Plasmodium falciparum in Botswana. The calibration curve was linear between 0.5 and 12 μg/mL with a coefficient of determination (R2 ) of 0.9996. The limit of detection and the lower limit of quantification were 0.5 and 1.4μg/mL, respectively. The efficiency of extraction measured as percentage recovery ranged between 84.2% and 107.8% at the three quality control (QC) levels, that is, low QC, mid QC, and high QC. In conclusion, data suggest that the method is suitable for the determination of trace Lum in biofluids and can also be used for therapeutic drug monitoring and pharmacokinetic profiling.

Neural Network Modelling for Prediction of Coagulant Dosage

Water treatment plants (WTP) in Indonesia commonly applied conventional treatment that, among others, relies on the coagulation process to treat turbid surface water to produce clean and safe water for daily purposes. Meanwhile, standard Jar-Test methods for coagulant dosage determination are inefficient, inaccurate, and possibly will not function well for water with high variability of quality. This study aims to improve and optimize the coagulant dosing process by considering the main parameter that greatly affects the coagulation process, i.e., turbidity. For this purpose, a multilayer artificial neural network model (ANN) with an adaptive backpropagation algorithm was developed using MATLAB software. A network architecture with 1 input, 5 hidden and 1 output was implemented. For the input, 4465 turbidity data of the raw water taken from Surabaya Municipal Water Enterprise (PDAM) were used, while the output is the optimal dose obtained from the results of the Jar-test. This study resulted in an empirical model of the optimum dosage of coagulants as a function of the turbidity of the raw water. Training and testing on the given ANN resulted in R2 (determination coefficient) of 0.99444 from regression analysis with the following equation: output = 0.99 x target + 0.66. This study showed that the ANN model provides a very high success rate for coagulant dose prediction.

Determination of 10 carbamate pesticide residues in liquid milk by ultra performance liquid chromatography-tandem mass spectrometry with pass-through solid-phase extraction purification

Carbamates are used in broad-spectrum insecticides and herbicides, and have highly efficient, low-residue, and long-lasting characteristics. However, this type of pesticide exerts mutagenic, teratogenic, carcinogenic, and other adverse effects, and its frequent use can exceed the recommended scope and limits. Research on the determination of carbamate pesticides mainly focuses on foods of plant origin and pays less attention to foods of animal origin. The methods for carbamate determination described in the current national standards have complicated operating procedures and low efficiency. Therefore, highly efficient and accurate methods for carbamate detection in milk must be established. In this work, a rapid method based on pass-through solid-phase extraction (SPE) purification coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was developed for the simultaneous determination of 10 carbamate pesticides in liquid milk. The pretreatment and instrument methods were systematically optimized. The milk sample was extracted with acetonitrile, and then purified using a Captiva EMR-Lipid filtration kit. The purified extract was separated on an ACQUITY UPLC BEH C18 column with mobile phase of methanol and 0.1% formic acid aqueous solution in gradient elution. The flow rate was 0.3 mL/min. Column temperature was 35 ℃. Quantitative analysis was performed using the external standard method with matrix matching curves. The 10 carbamate pesticides showed good linear relationships in the mass concentration range of 2-200 μg/L, with correlation coefficients greater than 0.999. The limits of detection (LODs) and quantification (LOQs) for the 10 carbamate pesticides were 0.045-0.23 and 0.15-0.77 μg/kg, respectively. Recovery tests were conducted using the blank-matrix method at three spiked levels of 15, 50, and 100 μg/kg, and good recoveries for the 10 carbamate pesticides were obtained. In particular, the recoveries for the three spiked levels of 15, 50, and 100 μg/kg were 68.7%-93.3% with relative standard deviations (RSDs) of 1.8%-8.0%. The proposed method is efficient, convenient, accurate, and suitable for the rapid detection of the 10 carbamate pesticides in liquid milk. Compared with the conventional NH2 and ENVITM-18 SPE columns used in the national standard determination method, the proposed method demonstrated better purification effects. The recoveries for aldicarb sulfoxide, aldicarb sulfone, methomyl, and carbaryl after purification using the Captiva EMR-Lipid kit increased from 60% to 80%. Thus, the proposed method is suitable for targets with strong polarity and gives measurement results with good repeatability and accuracy.

Develop an external standard method for high-flux determination of veterinary drug residues liquid milk without solid phase extraction

To get rid of the singularity of the detection of veterinary drug residues in liquid milk, a high-throughput determination was developed for 126 VDRs in 17 categories in liquid milk based on the one-step extraction coupled with LC-HRMS (UPLC-Q-Exactive-Orbitrap-MS). The results showed that adding 2.5 mL of 0.1 mol/L Na2EDTA-McIlvaine in acetonitrile-methanol extractant (50:50, V/V) could effectively improve the response intensity of veterinary drug residues in liquid milk, reduce the matrix effect and eliminate the need for expensive SPE purification. The established external standard quantitative method has a LOD of 0.01–0.30 μg/L for all categories of veterinary drug residues, good linearity in the concentration range of LOQ of 0.03–1.00 μg/L, and correlation coefficients (r2) were all greater than 0.995. The spike recoveries at all three levels were between 80.30% and 119.95%. The positive detection rate of this method in 128 actual samples was 8.59%.

Development and validation of a specialized system for self-tapping medical bone screw testing.

A specialized system for accurate self-tapping medical bone screw testing is developed, fully meeting the requirements of ASTM F543-A4 (YY/T 1505-2016). The onset of self-tap is identified automatically according to a change in the slope of the torque curve. Precise load control is applied to determine the self-tapping force accurately. A simple mechanical platform is embedded to ensure the automatic axial alignment of a tested screw with the pilot hole in a test block. In addition, comparative experiments are conducted on different self-tapping screws to verify the system's effectiveness. By the automatic identification and alignment method, both torque curves and axial force curves for each screw exhibit significant consistency. The self-tapping time point derived from the torque curve agrees well with the turning point of the axial displacement curve. The determined self-tapping forces' mean values and standard deviations are both small, which are proved to be effective and accurate in the insertion tests. This work contributes to improving the standard test method for accurate determination of the self-tapping performance of medical bone screws.

Influence of the Valid Test Temperature Range on Master Curve Analyses of Large Fracture Toughness Data Sets

Abstract ASTM E1921, Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range, standardizes the Master Curve procedure for determining the reference temperature, T0, of ferritic steels in the ductile-to-brittle transition range. In order for toughness test results to be included in the analyses, the corresponding test temperatures, T, must currently lie within the valid range defined as T0 – 50°C ≤ T ≤ T0 + 50°C. This study investigated the possibility of extending the valid test temperature range in a future revision of ASTM E1921 by assessing the consequences on the values of homogeneous (T0) and inhomogeneous (T0IN, Tm) reference temperatures calculated on 10 large “historical” data sets, already examined by the author in previous papers. The effect of expanding the valid temperature range on the macroscopical nature (homogeneous or inhomogeneous) of each data set was also considered by using the screening criterion presently proposed by ASTM E1921-22a. The results obtained appear to warrant a possible revision of the standard in this direction.

Temperature Dependence of Cleavage Fracture Toughness for an Ultrahigh Strength Martensitic Steel

Abstract This work conducts an exploratory evaluation of the brittle fracture behavior for an ultrahigh strength martensitic steel using conventional three-point bend SE(B) and precracked Charpy V-notch (PCVN) specimens. A primary purpose of this study is to verify the effectiveness of the Master Curve methodology in providing a reliable estimate of the reference temperature (T0) derived from fracture toughness data sets measured in the ductile-to-brittle transition (DBT) region of an ultrahigh strength, low alloy martensitic steel. Fracture toughness testing conducted on three-point bend SE(B) specimens and PCVN configurations at different test temperatures in the DBT region provides the cleavage fracture resistance data in terms of the J-integral at cleavage instability, Jc, and its corresponding KJc-values for the tested material. Although this class of ultrahigh strength steel having a martensitic microstructure is currently beyond the reach of ASTM E1921, Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range, the analyses described here show that the predicted normalized curves of median fracture toughness versus temperature are in good agreement with the experimental measurements.

Loading Rate of Fracture Toughness Tests in Transition Regime

Abstract ASTM E1921-21, Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range, contains a limitation on the stress intensity factor loading rate (K˙) for the quasistatic loading. The specimens should be loaded at a rate such that K˙ during the initial elastic portion is between 0.1 and 2 MPa√m/s. However, based on recent improvements in the test technique, it should be possible to narrow the loading rate range in order to reduce variability and have more comparable results between laboratories. For all users to be able to achieve the reduced range, clear guidelines are needed, which are not yet available. The Belgian Nuclear Research Centre (SCK CEN) has extensive experience in fracture toughness testing and has constructed a large database on which statistical studies were performed. This paper illustrates, using the SCK CEN database, that Wallin’s theoretical displacement formulas can only be used in the case in which the compliance of the testing setup is taken into account. An improved equation is proposed, guidelines for implementing the equation are drawn up, and these are verified using the database. It is clear that the methodology is sufficiently robust to provide an average loading rate within the suggested range of 0.5 and 2 MPa√m/s. This methodology could thus be integrated into the testing standard ASTM E1921-21.

Benchmark to Evaluate Revised Censoring Procedures for ASTM E1921

Abstract ASTM E1921, Standard Test Method for Determination of Reference Temperature, T0, for Ferritic Steels in the Transition Range, contains a censoring criterion, KJΔa, that limits the amount of ductile tearing prior to cleavage in specimen data used to calculate the reference temperature, T0. A frequent complaint from users is that the requirements for both determining and implementing KJΔa are unclear and difficult to apply. These provisions require that KJΔa be determined using either the maximum valid KJc data from another result within the data set (i.e., one with an acceptance amount ductile tearing prior to cleavage) or a K-value based on the material’s JIc value (i.e., KJIc). Both options are potentially problematic as the JIc value is often unknown and assigning other test data as the censoring value can cause situations where this value is higher than the measured KJc value for that specimen. A benchmark analysis evaluated two alternative options for ductile-tearing censoring requirements proposed to rectify these inadequacies. The first option uses an absolute ductile-tearing-limit criterion and is simpler to apply. The second option employs a ductile tearing limit that varies with the KJc result but is designed to minimize the conservative bias associated with excessive ductile tearing. Data sets for low upper-shelf materials with sufficient data to calculate valid T0 values, yet with a significant percentage of data with measurable ductile tearing prior to cleavage were selected for evaluation. The benchmark results illustrated that although there is no obviously better censoring option, the option that uses an absolute ductile-tearing-limit is simpler to implement, whereas the T0 results are generally consistent with those calculated for the option with the variable ductile-tearing-limit.

Glycemic Index and Amylose Content of 25 Japonica Rice Italian Cultivar

The glycemic index (GI) was developed to classify foods according to their ability to increase postprandial blood glucose. The literature reports that the GI of rice varieties ranges from 48 to 93. All studies evaluate Indica rice but none evaluates the GI of Japonica rice. Furthermore, no studies have been conducted to assess the relationship between amylose content and GI in Japonica rice. The aim of this study is to evaluate the GI and amylose content of 25 Japonica rice genotypes.This study is based on the standard method for GI determination according to the international standard ISO 26642; it includes two men and eight women (mean age 28.3 ± 3.7, Body Mass Index – BMI – 21.4 ± 2.6). Five rice genotypes show low GI (Selenio, Argo, Enr18215, Enr18328, Enr18433), 10 medium GI (Carnaroli, CL12, CL388, CRLB1, Elio, Enr18126, Iarim, S. Andrea, Tiberio, and Valente), and 10 high GI (Arborio, Lince, Duilio, Castelmochi, Padano, Puma, Baldo, CL18, CL35, CL71). A negative association is also observed between medium GI and amylose (r = −0.528). As the amylose content increases, the mean GI decreases.Five rice genotypes have a low GI and are therefore suitable for a healthy diet and for diabetics.

Detailed band alignment of high-B-composition BGaN with GaN and AlN

The electronic structure of B0.097Ga0.903N was determined by examining its bandgap and valence band offset (VBO) in detail. The BGaN sample was grown using a horizontal reactor metalorganic chemical vapor deposition. For bandgap determination, three different techniques were utilized yielding similar results, which are: UV–Vis spectroscopy, Schottky photodiodes, and electron energy-loss spectroscopy. The bandgap was determined to be ∼3.55 eV. For measuring the VBO, the valence edges and the core levels of Al 2s and Ga 2p were measured using x-ray photoelectron spectroscopy (XPS). The valence edges were then fitted and processed along with the core levels using the standard Kraut method for VBO determination with AlN. The BGaN/AlN alignment was found to be −1.1 ± 0.1 eV. Due to core level interference between GaN and BGaN, the Kraut method fails to provide precise VBO for this heterojunction. Therefore, a different technique is devised to analyze the measured XPS data which utilizes the alignment of the Fermi levels of the BGaN and GaN layers when in contact. Statistical analysis was used to determine the BGaN/GaN alignment with decent precision. The value was found to be −0.3 ± 0.1 eV.

A swallowable X-ray dosimeter for the real-time monitoring of radiotherapy.

Monitoring X-ray radiation in the gastrointestinal tract can enhance the precision of radiotherapy in patients with gastrointestinal cancer. Here we report the design and performance, in the gastrointestinal tract of rabbits, of a swallowable X-ray dosimeter for the simultaneous real-time monitoring of absolute absorbed radiation dose and of changes in pH and temperature. The dosimeter consists of a biocompatible optoelectronic capsule containing an optical fibre, lanthanide-doped persistent nanoscintillators, a pH-sensitive polyaniline film and a miniaturized system for the wireless readout of luminescence. The persistent luminescence of the nanoscintillators after irradiation can be used to continuously monitor pH without the need for external excitation. By using a neural-network-based regression model, we estimated the radiation dose from radioluminescence and afterglow intensity and temperature, and show that the dosimeter was approximately five times more accurate than standard methods for dose determination. Swallowable dosimeters may help to improve radiotherapy and to understand how radiotherapy affects tumour pH and temperature.

458 Assessment of MGMT Methylation Status Using High-Performance Liquid Chromatography in Newly Diagnosed Glioblastoma

INTRODUCTION: The utility of O6-methylguanine-DNA methyltransferase (MGMT) gene promoter methylation status as a prognostic marker in patients with glioblastoma (GBM) has been established. However, the number of CpG sites that must be methylated to cause transcriptional silencing remains unclear, and no significant consensus exists on the optimal method of assessing MGMT methylation. METHODS: W analyzed the MGMT methylation status of 28 isocitrate dehydrogenase–wild-type GBMs treated with temozolomide using ion-exchange HPLC and bisulfite sequencing using frozen samples. We designed three primers for separate regions (regions 1–3) that had 21 to 38 CpGs for PCR and validated the MGMT promoter methylation status. RESULTS: There was a strong correlation between HPLC and bisulfite sequencing results (R = 0.794). The optimal cutoff values for MGMT methylation in HPLC were determined to allow differentiation of patient prognosis by receiver operating characteristic curve analysis. The cutoff values were 34.15% for region 1, 8.84% for region 2, and 36.72% for region 3. Kaplan–Meyer curve analysis estimated that the most differentiated prognosis was enabled in the setting of 8.84% methylation of MGMT in region 2. Progression-free survival and overall survival were significantly longer for patients in this setting of region 2 methylation (p = 0.00365 and p = 0.00258, respectively). CONCLUSIONS: The combination of our HPLC method and the original primer setting provides a new standard method for determination of MGMT methylation status in patients with GBM and is useful for refining MGMT-based drug selection.

Detecting and Profiling of Milk Thistle Metabolites in Food Supplements: A Safety-Oriented Approach by Advanced Analytics

Milk thistle (Silybum marianum (L.) Gaertn.) is among the top-selling botanicals used as a supportive treatment for liver diseases. Silymarin, a mixture of unique flavonolignan metabolites, is the main bioactive component of milk thistle. The biological activities of silymarin have been well described in the literature, and its use is considered safe and well-tolerated in appropriate doses. However, commercial preparations do not always contain the recommended concentrations of silymarin, failing to provide the expected therapeutic effect. While the poor quality of raw material may explain the low concentrations of silymarin, its deliberate removal is suspected to be an adulteration. Toxic contaminants and foreign matters were also detected in milk thistle preparations, raising serious health concerns. Standard methods for determination of silymarin components include thin-layer chromatography (TLC), high-performance thin-layer chromatography (HPTLC), and high-performance liquid chromatography (HPLC) with various detectors, but nuclear magnetic resonance (NMR) and ultra-high-performance liquid chromatography (UHPLC) have also been applied. This review surveys the extraction techniques of main milk thistle metabolites and the quality, efficacy, and safety of the derived food supplements. Advanced analytical authentication approaches are discussed with a focus on DNA barcoding and metabarcoding to complement orthogonal chemical characterization and fingerprinting of herbal products.