Test Solution Research Articles

CORROSION INHIBITION BEHAVIOUR OF CUSTARD APPLE LEAVES AND ACACIA CONCINNA EXTRACT ON MILD STEEL IN ACIDIC MEDIA: ADSORPTION AND THERMODYNAMIC STUDY

Custard apple leaves extract (CALE) was tested to evaluate corrosion inhibition efficiency for mild steel under acidic medium. The test metal substrate was collected over a period of 24 hr of contacting with acid to determine the corrosion inhibition efficiency (CIE) and corrosion rate (CR) using the Gravimetric analysis. The findings of the study were applied to examine the adsorption behavior and thermodynamic characteristics for CALE as a potential corrosion inhibitor in acidic environment. Mild steel exhibited the highest corrosion rate in the absence of a corrosion inhibitor in a 0.5 M sulphuric acid solution. However, the rate of corrosion was observed to decrease gradually with increase in CALE concentration (0.4–2.0 g/l). The similar trend was noted at the experimental temperature range of 298-328 K. Adsorption behavior was investigated using the Langmuir, Temkin, Freundlich, and Flory Huggins adsorption isotherm models. The Temkin adsorption isotherm model provides the best fit to the experimental data. Besides, the negative values of Gibb’s free energy of adsorption (ΔGad) reveal strong evidence for the spontaneous nature of CALE adsorption on mild steel surface. The increase in activation energy (Ea) from 35.05 kJ/mol in the blank test solution to 68.03 kJ/mol at 2.0 g/l concentration of CALE indicates the formation of a protective film of inhibitor molecules on the metal surface. Adsorption enthalpy values (∆H=31.28-73.79 kJ/mol) over the concentration range (0-2.0g/l of CALE) implies physical adsorption, whereas negative entropy values (ΔS) suggests free movement of inhibitor molecules in the bulk solution. Additionally, a synergistic effect was demonstrated in lowering the corrosion rate by combining Acacia concinna extract (ACE, 0.1-0.3 g/l) with CALE, thereby enhancing the overall corrosion inhibition efficiency. For citation: Jitendra Kisan Shinde, Ravindra Gulab Puri, Pawan Devidas Meshram, Rajkumar Shankarrao Sirsam Corrosion inhibition behaviour of Custard apple leaves and Acacia concinna extract on mild steel in acidic media: adsorption and thermodynamic study. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2024. V. 67. N 7. P. 119-126. DOI: 10.6060/ivkkt.20246707.7038.

VIP - Variational Inversion Package with example implementations of Bayesian tomographic imaging

Bayesian inference has become an important methodology to solve inverse problems and to quantify uncertainties in their solutions. Variational inference is a method that provides probabilistic, Bayesian solutions efficiently by using optimisation. In this study we present a Python Variational Inversion Package (VIP), to solve inverse problems using variational inference methods. The package includes automatic differential variational inference (ADVI), Stein variational gradient descent (SVGD) and stochastic SVGD (sSVGD), and provides implementations of 2D travel time tomography and 2D full waveform inversion including test examples and solutions. Users can solve their own problems by supplying an appropriate forward function and a gradient calculation code. In addition, the package provides a scalable implementation which can be deployed easily on a desktop machine or using modern high performance computational facilities. The examples demonstrate that VIP is an efficient, scalable, extensible and user-friendly package, and can be used to solve a wide range of low or high dimensional inverse problems in practice.

Sorption of colored vs. noncolored organic matter by tidal marsh soils

Abstract. Tidal marshes are significant sources of colored (or chromophoric) dissolved organic carbon (CDOC) to adjacent waters and, as a result, contribute substantially to their optical complexity and ultimately affect their water quality. Despite this, our mechanistic understanding of the processes that regulate the exchange and transformation of CDOC at the tidal marsh–estuarine interface remains limited. We hypothesized that tidal marsh soils regulate this exchange and transformation subject to soil mineralogy and salinity environment. To test this hypothesis, we generated initial mass sorption isotherms of CDOC and noncolored dissolved organic carbon (NCDOC) using anaerobic batch incubations of Great Dismal Swamp DOC with four tidal wetland soils, representing a range of organic carbon content (1.77 ± 0.12 % to 36.2 ± 2.2 %) and across four salinity treatments (0, 10, 20, and 35). CDOC sorption followed Langmuir isotherms that were similar in shape to those of total DOC, but with greater maximum sorption capacity and lower binding affinity. Like isotherms of total DOC, CDOC maximum sorption capacity increased and binding affinity decreased with greater salinity. Initial natively adsorbed colored organic carbon was low and increased with soil organic content. In contrast, NCDOC desorbed under all conditions with desorption increasing linearly with initial CDOC concentration. This suggests that for our test solutions CDOC displaced NCDOC on tidal marsh soils. Parallel factor analysis of 3-D excitation emission matrices and specific ultraviolet absorbance measurements suggested that CDOC sorption was driven primarily by the exchange of highly aromatic humic-like CDOC. Taken together, these results suggest that tidal marsh soils regulate export and composition of CDOC depending on the complex interplay between soil mineralogy, water salinity, and CDOC vs. NCDOC composition.

Glucose appetition in C57BL/6J mice: Influence of nonnutritive sweetener experience, food deprivation state and sex differences

In addition to its sweet taste, glucose has potent and rapid postoral actions (appetition) that enhance its reward value. This has been demonstrated by the experience-induced preference for glucose over initially preferred nonnutritive sweetener solutions in 24-h choice tests. However, some sweetener solutions (e.g., 0.8% sucralose) have inhibitory postoral actions that may exaggerate glucose appetition whereas others (e.g., 0.1% sucralose + 0.1% saccharin, S+S) do not. Experiment 1 revealed that food-restricted (FR) male C57BL/6J mice displayed similar rapid glucose appetition effects (stimulation of glucose licking within minutes) and conditioned flavor preferences following 1-h experience with flavored 0.8% sucralose or 0.1% S+S and 8% glucose solutions. Thus, the inhibitory effects of 0.8% sucralose observed in 24-h tests were not apparent in 1-h tests. Experiment 2 evaluated the effects of food deprivation state and sweetener concentration on glucose appetition in female mice. Unlike FR mice tested with 0.1% S+S and 8% glucose, ad libitum (AL) fed mice displayed no stimulation of 8% glucose licking in the 1-h tests. A second ad libitum group (AL) tested with 0.2% S+S and 16% glucose solutions displayed stimulation of 16% glucose licking by the third 1-h test. Both AL groups, like the FR group, developed a preference for the glucose-paired flavor over the S+S paired flavor. Thus, food restriction promotes increased glucose licking but is not required for a conditioned preference. The FR male mice (Exp. 1) and FR female mice (Exp. 2) showed similar appetition responses (licking stimulation and flavor preference) to 8% glucose.

Correlating corrosion modes with the microstructure of the 2XXX series alloys: A comparative approach

In this study, the localized corrosion susceptibility of AA2050‐T84, AA2198‐T851, and AA2024‐T3 alloys was compared by immersion in three test solutions, specifically sodium chloride solution (3.5% NaCl), EXCO solution, according to ASTM G34‐18, and a solution for intergranular corrosion (IGC) test recommended by ASTM G110‐15 and via scanning vibrating electrode technique (SVET). The results showed higher susceptibility of AA2050‐T84 alloy to all types of corrosion tested compared to the other studied 2XXX series alloys. Corrosion penetration was deeper in the AA2050‐T84 due to its microstructural characteristics as a difference in the micrometric Cu‐Rich intermetallic particle distribution on the surface and related to the distribution of the T1 (Al2CuLi) phase.

Liver function and portal-systemic shunting quantified by the oral cholate challenge test and risk for large oesophageal varices.

The quantitative HepQuant SHUNT test of liver function and physiology generates a disease severity index (DSI) that correlates with risk for clinical complications, such as large oesophageal varices (LEVs). A derivative test, HepQuant DuO, generates an equivalent DSI and simplifies testing by requiring only oral administration of the test solution and two blood samples at 20 and 60 min. Since the DSIs measured from DuO and SHUNT are equivalent, we compared the diagnostic performance for large oesophageal varices (LEVs) between the DSIs measured from DuO and SHUNT tests. This study combined the data from two prospectively conducted US studies: HALT-C and SHUNT-V. A total of 455 subjects underwent both the SHUNT test and esophagogastroduodenoscopy (EGD). DSI scores correlated with the probability of LEVs (p < 0.001) and demonstrated a stepwise increase from healthy lean controls without liver disease to subjects with chronic liver disease and no, small or large varices. Furthermore, a cutoff of DSI ≤ 18.3 from DuO had a sensitivity of 0.98 (missing only one case) and, if applied to the endoscopy (EGD) decision, would have prevented 188 EGDs (41.3%). The AUROC for DSI from DuO did not differ from that of the reference SHUNT test method (0.82 versus 0.81, p = 0.3500). DSI from HepQuant DuO links liver function and physiology to the risk of LEVs across a wide spectrum of patient characteristics, disease aetiologies and liver disease severity. DuO is minimally invasive, easy to administer, quantitative and may aid the decision to avoid or perform EGD for LEVs.

Submodels of 2-d model of the motion of fluid or gas in a porous medium with an external non-stationary source or absorption

The motion of fluid or gas in a porous medium is the main object of investigation of underground hydromechanics. The model describing this motion was called “Porous medium”.In our paper, we study a general 2-d model of the motion of fluid or gas in porous medium with an external non-stationary source or absorption. As the main research method, we use the method of group (symmetry) analysis, which is one of the most effective ways to obtain information about the properties of solutions to differential equations that define a physical model. A group classification of the differential equation defining studied physical model is carried out. As a result, all basic models with different symmetry properties are obtained. For the basic model, which admits the widest group a classification of all its invariant submodels is performed and all invariant submodels, defined by invariant solutions of rank 1 are studied. All solutions found have physical meaning.The set of explicitly found solutions forms a 47-parametric family of exact solutions. Each solution in this family depends on an arbitrary function defining an external non-stationary source or absorption. For each solution, for the specific values of the parameters on which it depends and for this specific function, we obtained a graph of the pressure distribution.Other solutions are used to describe the movement of a liquid or gas if either the pressure and its rate of change, or the pressure and one of its gradient components, are given at an initial time at a fixed point. The set of these solutions depends on 13 parameters and a function defining an external non-stationary source or absorption. For specific values of this function and specific values of the parameters on which each solution depends, the existence and uniqueness of a solution to the corresponding boundary value problem under some additional conditions has been established. Each such problem is solved numerically. The results of these decisions we reflected in the graphs.The significance of obtained solutions lies in the fact that we have obtained a database consisting of two multiparameter families of invariant solutions of rank 1 of the equation describing the motion of fluid or gas in a porous medium in the presence of an external non-stationary source or absorption. Every solution depends on an empirically determined function. These solutions describe specific physical processes. They can also be used as test solutions in numerical calculations related to the study of the motion of fluid or gas in a porous medium during fluids filtering, engineering surveys in the construction of building structures and in the extraction of shale oil or gas.

Improving the Current European Pharmacopoeia Enantio-Selective HPLC Method for the Determination of Enantiomeric Purity in Atorvastatin Calcium Salt Drug Substance

Atorvastatin (ATV) is a well-established lipid-lowering agent. ATV has two stereogenic centers, and of the four possible stereoisomers, only the (3R,5R) form is used therapeutically. The European Pharmacopoeia (EP) monograph 2022 for ATV calcium salt describes a normal-phase high-performance liquid chromatography (HPLC) method for the determination of enantiomeric purity in both drug substance and working standard samples, based on a 150 mm × 4.6 mm Chiralpak AD-H column. The main problems with this method are the very long analysis time and the high solvent consumption. Here, an alternative chromatographic protocol was developed using the Chiralpak AD-3 column (250 mm × 4.6 mm) packed with 3 μm silica particles instead of the 5 μm silica particles of the Chiralpak AD-H chiral stationary phase and characterized by the same polysaccharide selector, amylose-tris(3,5-dimethylphenylcarbamate). Using a mobile phase consisting of a mixture of n-hexane-ethanol-formic acid 90:10:0.1 (v/v/v) as the mobile phase and setting the flow rate and column temperature to 1.0 mL min−1 and 35 °C, respectively, a simultaneous stereo-selective separation was achieved within 35 min without observing any overlap between the enantiomeric impurity peak and peaks related to other ATV impurities. Compared to HPLC EP conditions, the analysis time to elute all the potentially related substances was faster and significantly less mobile phase volume was required. The linearity of the method has been demonstrated in the range of 4.4 μg mL−1 to 1000 μg mL−1 (R2 &gt; 0.999). At a concentration of 4.4 μg mL−1, which is 0.075% of the test solution (5.8 mg mL−1, as ATV free acid), the signal-to-noise ratio was found to be 20.

A Microfluidic Paper-Based Lateral Flow Device for Quantitative ELISA

This study presents an innovative lateral flow microfluidic paper-based analytical device (μPAD) designed for conducting quantitative paper-based enzyme-linked immunosorbent assays (p-ELISA), seamlessly executing conventional ELISA steps in a paper-based format. The p-ELISA device utilizes a passive fluidic circuit with functional elements such as a multi-bi-material cantilever (B-MaC) assembly, delay channels, and a buffer zone, all enclosed within housing for autonomous, sequential loading of critical reagents onto the detection zone. This novel approach not only demonstrates a rapid assay completion time of under 30 min, but also boasts reduced reagent requirements, minimal equipment needs, and broad applicability across clinical diagnostics and environmental surveillance. Through detailed descriptions of the design, materials, and fabrication methods for the multi-directional flow assay (MDFA), this manuscript highlights the device’s potential for complex biochemical analyses in a user-friendly and versatile format. Analytical performance evaluation, including a limit of detection (LOD) of 8.4 pM for Rabbit IgG, benchmarks the device’s efficacy compared to existing p-ELISA methodologies. This pioneering work lays the groundwork for future advancements in autonomous diagnostics, aiming to enhance global health outcomes through accessible and reliable testing solutions.

A Modified Enthalpic Lattice Boltzmann Method for Simulating Conjugate Heat Transfer Problems in Non-Homogeneous Media

A Modified Enthalpic Lattice Boltzmann Method for Simulating Conjugate Heat Transfer Problems in Non-Homogeneous Media

Accelerating cell therapy production: realizing the advantages of rapid analytical testing solutions

Accelerating cell therapy production: realizing the advantages of rapid analytical testing solutions

Synthesis of Ag/NiFe2O4 doped multiwalled carbon nanotube for antibiotic removal from water

Antibiotics impose severe impacts on humans and the ambient water environment by creating antimicrobial resistance in bacterial pathogens; therefore, there exists an urgent need to develop sustainable and efficient adsorbents for the removal of these contaminants from the water. To this goal, silver/nickel ferrite-doped multiwalled carbon nanotubes (Ag/NiFe2O4 doped MWCNTs) were prepared as functional integrated adsorbent material for antibiotic removal from water. The TEM results showed that Ag/NiFe2O4 species were dispersed on the surface of MWCNTs through the available functional groups on their surface. The introduction of Ag/NiFe2O4 nanocomposite onto the MWCNTs efficiently improved the adsorption capacity for ciprofloxacin. The maximum adsorption capacity is estimated to be 26.45 mg/g. The results indicated a higher adsorptive capacity for the produced ternary sample compared to pristine MWCNTs, Ag/NiFe2O4, or NiFe2O4/MWCNTs binary systems. The adsorption capacity for ciprofloxacin in the samples was evidently dependent on the MWCNTs dose, solution pH, adsorbate dose, and temperature. Ag/NiFe2O4 doped MWCNTs (65 % w/w) were able to remove ∼95 % of ciprofloxacin in the testing solution even after being reclaimed for 4 times following the Langmuir isotherm model in the endothermic manner. Also, the adsorption of CIP by the nanocomposite demonstrates a pseudo-second-order model. These promising results open a pathway for efficient carbon materials to be replaced by conventional adsorbents to remove antibiotics from water.

Investigation of structure, morphology, and corrosion behavior of carboxylic acids/hydroxyapatite/chitosan coatings on Ti discs for implants

Titanium (Ti) and its alloys are widely used in bone defect repair owing to their advantages, including high strength, corrosion resistance, and biocompatibility. The formation of a stable oxide layer on Ti implants enhances the osseointegration process. Nevertheless, additional progress is required to improve the incorporation of these implants at the microscopic and nanoscopic levels to achieve a biocompatible interface. The main objective of this study was to enhance the morphology of hydroxyapatite and the corrosion resistance of Ti implants by applying hydroxyapatite/chitosan (HA/Cs) nanocomposite coatings embedded with carboxylic acids. The coatings were fabricated by electrodeposition, wherein various acid concentrations (acrylic and acetic acids) were employed as Cs electrolyte solvents to enhance the adhesion and bond strength with the titanium metal substrate. The microstructures of the HA/Cs coatings were analyzed using X-ray diffraction. The results demonstrated that the structure of HA was affected by the type of acid used and its concentration as the crystallinity increased with a high concentration of acrylic acid. Additionally, the morphology of HA/Cs was analyzed using a transmission electron microscope. The results showed that the morphology of HA/Cs changed from a hexagonal rod-like shape with acrylic acid samples into a needle-like shape in acetic acid samples. The corrosion behavior was investigated using electrochemical impedance spectroscopy (EIS) in a simulated body fluid (SBF) at 37±2ºC. The EIS results showed a high corrosion resistance with phase angles close to −80° and high impedance values of 80.5 kΩ cm2 with a high concentration of acrylic acid. These results indicated the formation of a highly adhesive and stable film on the implants in the test solution. In conclusion, based on this study and our previous work, the corrosion resistance, good biocompatibility, and biomineralization properties of the prepared HA/Cs-coated Ti recommend it as an alternative implant for clinical applications.

Real-time and high-sensitive colorimetric sensor based on photonic crystal for amniotic fluid identification

In this study, we proposed a pH-responsive photonic crystal hydrogel sensor (PCHs) to conveniently and accurately recognize the amniotic fluid from urine of parturient women, which was constituted by three-dimensional polymethyl acrylamide (PMMA) array and optimized hydrogel. PMMA array was self-assembled by 180 nm monodispersed nanoparticles with vertical sedimentation method. The functional hydrogel containing N-acryloyl phenylalanine (APA), acrylamide (AM) and N, N'-methylene bis(acrylamide) (BIS) as co-monomer and crosslinking agent respectively, was photo-polymerized by the precursor under 365 nm UV light. This hydrogel significantly shrank or swelled corresponding to the acidity and alkalinity of the aqueous solution, which resulted in both the reflection peak position (λmax) of the prepared sensor and its structural color changing with the pH value. The λmax of PCHs redshifted from 514 nm to 606 nm in 60 s while the pH value of testing solution increased from 4.5 to 8.0, which exactly covered the pH value of amniotic fluid and urine. Correspondingly, its structure color gradually changed from pale-green to red ensuring their naked-eye determination. Furthermore, an extremely high sensitivity as 26.3 nm/pH of Δλmax was obtained which was linearly related to pH value. The prepared sensor possessed steady accuracy and extraordinary sensitivity compared with the pH test strip which was generally used in amniorrhexis diagnosis nowadays besides the advantages of the low cost, simple operation, rapid response and visual detection mode. The reliability of this PCHs was further confirmed by the real sample detection which relative standard deviation was below 5.0 %, suggesting its potential clinical applications.

From flat to folded: An instrument-free solution for chemical and biological paper-based sensing using A-PAP pen technology

Having economical, flexible, disposable and readily manufacturable devices for everyday sensing applications is of paramount importance. We report a novel and cost-effective technique for fabricating paper-based devices using an Advanced PAP (A-PAP) pen, which is capable of withstanding typical aqueous solutions and organic solvents. The quick fabrication process does not require any sophisticated instrumentation or a heating step, making it a promising technology for resource-limited settings. Using an A-PAP pen, we have fabricated two-dimensional (2D) paper-based devices for chemical detection of heavy metal and nitrite. We have also demonstrated the versatility of fabrication technique for biological sensing using 2D lateral flow paper-based devices for the detection of dopamine. Furthermore, the technique is also validated for fabricating complex three-dimensional (3D) paper-based devices using a paper origami technique for heavy metals sensing. The ready-to-use devices can be fabricated in seconds, making them convenient for on-the-spot testing. Overall, this technique provides a valuable tool for creating affordable, efficient, and accessible chemical and biological testing solutions.

Antibacterial activity of Kemloko fruit ethanol extract (Phyllanthus emblica L.) against Staphylococcus aureus and MRSA bacteria

Background: Indonesia is a tropical country, so the prevalence of infectious diseases caused by bacteria remains high. On the other hand, the high use of antibacterial ingredients in Indonesia causes bacterial resistance to existing antibacterial drugs. One of the herbal plants that some people widely use is Kemloko fruit. This study aimed to determine the activity of Kemloko fruit (Phyllanthus emblica L.) ethanol extract against the growth of Staphylococcus aureus and methicillin-resistant Staphylococcus aureus (MRSA) bacteria. Methods: Simplicia of Kemloko fruit were tested for secondary metabolites and characterization test of the simplicia. The antibacterial activity test was carried out using the diffusion method, where the disc paper was immersed in the test solution with the ratio of the test concentration. Results: The results of phytochemical screening showed that the secondary metabolite compounds of Kemloko fruit are alkaloids, flavonoids, steroids, tannins, saponins, and glycosides. Antibacterial activity of ethanol extract of Kemloko fruit with agar diffusion method effectively inhibits S. aureus bacteria, namely at a concentration of 80 mg/ml, the inhibition zone is 14.1 mm, and at a concentration of 100 mg/ml, MRSA bacteria obtained an inhibition zone of 14.3 mm. Conclusions: The ethanol extract inhibits the growth of S. aureus and MRSA.

Not all that glitters is gold: Glitter causes acute toxicity to nauplii of Artemia sp.

Glitter has been reported as a relevant pollutant, as it is widely used in cosmetic and textile products and craftwork, and often associated with domestic sewage. The particular glitter is composed of thin layers of plastic and metal. This study assessed the acute toxicity of glitter dispersions in the brine shrimp Artemia sp. Nauplii of Artemia sp. that were exposed to glitter dispersions (0.01, 0.1, 1, 10, and 100 mg/L), obtained by diluting a stock solution in seawater; the control consisted of filtered seawater only. Three replicates were used per treatment and consisted of glass tubes filled with 10 mL of the test solution, and ten nauplii aging over 48 h. After 48 h, the survivors were counted and examined under a microscope. The mean size of glitter particles was 3.94 (±0.98) µm; approximately 44 % of particles were in the range of very fine sand, and 27 % coarse silt. Significant lethal effects (p &lt; 0.05) occurred from 0.1 mg/L (Lowest Observed Effect Concentration - LOEC); the lethal concentration to 50 % organisms (LC50-48h) was 0.350 (0.348 - 0.351) mg/L. The exposed organisms also exhibited patches in their digestive tracts, and particles were stranded in their appendices. The results indicate the toxic potential of glitter to brine shrimp. This investigation indicates the need for further studies on the toxicity of glitter to marine invertebrates. Highlights Glitter includes particles of sizes similar to those of marine microalgae Exposure to glitter suspensions caused toxicity in brine shrimps from 0.1 mg/L The nauplii of Artemia were more sensitive to glitter than echinoderm embryos Metallic parts of the glitter were observed in the digestive tract of the brine shrimp nauplii

Analytical and clinical validation of a novel, laboratory-developed, modular multiplex-PCR panel for fully automated high-throughput detection of 16 respiratory viruses

Background: Viral respiratory Infections pose a health risk, especially to vulnerable patient populations. Effective testing programs can detect and differentiate these infections at an early stage, which is particularly important for high-risk clinical departments. The objective of this study was to develop and validate a multiplex PCR-panel for 16 different respiratory viruses on a fully-automated high-throughput platform. MethodsThree multiplex-PCR assays were designed to run on the cobas5800/6800/8800 systems, consolidating 16 viral targets: RESP1: SARS-CoV-2, influenza-A/B, RSV; RESP2: hMPV, hBoV, hAdV, rhino-/ENV; RESP3: HPIV-1–4, hCoV-229E, hCoV-NL63, hCoV-OC43, hCoV-HKU1. Analytic performance was evaluated using digital-PCR based standards and international reference material. Clinical performance was determined by comparing results from clinical samples with reference assays. ResultsAnalytical sensitivity (i.e. lower limit of detection (LoD), 95 % probability of detection) was determined as follows: SARS-CoV-2: 29.3 IU/ml, influenza-A: 179.9 cp/ml, influenza-B: 333.9 cp/ml and RSV: 283.1 cp/ml. LoDs of other pathogens ranged between 9.4 cp/ml (hCoV-NL63) and 21,419 cp/ml (HPIV-2). Linearity was verified over 4–7 log-steps with pooled standard differentials (SD) ranging between 0.18–0.70ct. Inter-/intra-run variability (precision) was assessed for all targets over 3 days. SDs ranged between 0.13–0.74ct. Positive agreement in clinical samples was 99.4 % and 95 % for SARS-CoV-2 and influenza-A respectively. Other targets were in the 80–100 % range. Negative agreement varied between 96.3–100 %. DiscussionLab-developed tests are a key factor for effective clinical diagnostics. The multiplex panel presented in this study demonstrated high performance and provides an easily scalable high-throughput solution for respiratory virus testing, e.g. for testing in high-risk patient populations.

Cytotoxicity Test of Ethyl Acetate Fraction and Ethanol Fraction of Papaya Leaf Extract (Carica Papaya. L) Against Hep-2 Laryngeal Cancer Cells

Papaya leaves are used as medicine for fever, malaria, increased appetite, constipation, and anti-cancer. In the previous study using the Brine Shrimp Lethality Test (BSLT), an ethanol extract of papaya leaf had an LC50 value of 23.73 mg/mL. This suggests that papaya leaves are a compound, that uses a 70% ethanol extract of papaya leaves and has cytotoxic potential. Research objectives: This research aimed to determine the cytotoxic effect of the ethanol and ethyl acetate fractions of a 70 % ethanol extract of papaya leaf against Hep-2 cells. Performed in vitro by the direct calculation method (viable cell count), so its LC50 is known. The ethanol and ethyl acetate fraction of papaya leaf extract as a test solution was made in 5 concentrations, with concentrations of 20.93; 16.26; 12.64; 9.82, and 7.63 µg/ml. Result: The results obtained the LC50 ethanol fraction of 11.2616 μg/ml and the ethyl acetate fraction of LC50 12.4 of 882 μg/ml. Conclusion: Based on this, it can be concluded that the fraction of ethanol and ethyl acetate extracts of papaya (Carica papaya L.) have cytotoxic properties against Hep-2 cells in a range that goes very, very toxic, i.e., 5–50 µg/ml, and have the potential to be developed as an anticancer drug.

Sistem Kontrol Kadar Amonia Dan Tinggi Air Pada Kolam Penangkaran Tukik Penyu

Turtles are also one of the animals whose population is decreasing day by daydue to several factors ranging from climate change, disease, environmentaldamage and inadequate processing of conservation techniques and so on. Withthe status of turtles being endangered, special attention is needed for turtles inthe form of cultivating turtles, especially when the turtles are still 0-2 years oldor known as hatchlings. One of the important indicators in hatchling cultivationrequires good seawater quality management. One of the parameters of goodseawater quality is ammonia levels. This ammonia level can be formed naturallyby metabolic wastes and also food waste that decomposes in the water whichresults in the formation of ammonia levels. In turtle hatchling ponds it is alsonecessary to adjust the water level in the pond with a height of 5cm - 10cmbecause newborn hatchlings cannot dive. The importance of regular waterquality control such as ammonia levels and water level in ponds is veryimportant for the success of hatchling cultivation. Therefore, a research onmonitoring and controlling systems for ammonia levels and water levels usingthe TCS3200 color sensor is carried out to read the change in water color afteradministration of an ammonia test solution which will show the value ofammonia levels in water. Previously, water sampling was carried out by DCpumps and ultrasonic sensors to detect water level. Where this system canmonitor and control ammonia levels and height automatically and the resultscan be viewed using a smartphone through the Blynk application