Jurnal Pendidikan Kimia
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Comparison of Organic Liquid Soap Made from Papaya-Turmeric and Aloe Vera-Piper Betel
Get PDFIn the wake of the COVID-19 pandemic, the imperative to mitigate pathogen transmission has catalyzed the innovation of soaps imbued with antimicrobial and antibacterial properties. Diverging from conventional reliance on synthetic chemicals, often associated with adverse dermatological reactions, this study explores the formulation of organic liquid soaps. These soaps leverage naturally occurring antibacterial and antimicrobial compounds from readily accessible plants, presenting a viable alternative to commercially available inorganic body washes predominantly manufactured by small to medium-sized enterprises. Specifically, this research harnesses papaya and aloe vera extracts for their antimicrobial attributes, augmented with turmeric and piper betel for enhanced antibacterial efficacy. Despite the recognized potency of turmeric and piper betel, variability in their effectiveness necessitates rigorous validation against the Indonesian National Standards (SNI) to ensure product quality and safety. This includes comprehensive evaluations of pH levels, density, Total Plate Count (TPC), and Mold and Yeast Count (MYC) to certify the soap's inhibitory capacity against bacterial and fungal proliferation. Employing maceration and hot processing techniques, the formulated papaya-based soap adhered to SNI 4085:2017 criteria for pH and MYC, although initially failing the TPC test. Subsequent incorporation of turmeric extract facilitated compliance with all SNI benchmarks. Conversely, aloe vera formulations only satisfied pH requirements under the SNI, even after adding piper betel. However, substituting piper betel with turmeric extract enabled the aloe vera soap to fulfill the requisite SNI parameters. These findings underscore turmeric extract's superior antibacterial properties, positioning it as a pivotal component in papaya and aloe vera soap formulations. Contrary to prevalent assumptions regarding piper betel's antimicrobial and antibacterial effectiveness, our investigation substantiates turmeric's superior role in bacterial growth inhibition within organic soap matrices
Optimization of Antibacterial Edible Film Formulation Based on Chitosan, Velvet Bean Ethanol Extract, and Cinnamon Essential Oil
Get PDFThe existing research on edible films as packaging materials has maintained that they are better in constituent materials, composition, and functionality. Due to their good bioactivity, edible films are utilized for packaging, which is considered bioactive. The recent study focused on using chitosan-velvet bean (Mucuna pruriens (L.) DC.) based edible bioactive packaging formulation for antibacterial activity. Velvet bean ethanol extract (V) accompanied by cinnamon (Cinnamomum burmannii (Ness) BL) essential oil (C) which is effective as an antibacterial against Escherichia coli ATCC 25922 and Staphylococcus aureus ATCC 25923. Based on this study, the ascertained concentrations of V and C can generate the most optimum edible film associated with antibacterial activity and characterize the physical properties and morphology of the most optimum formulation of antibacterial edible film. It was proved that by addition of 30% V and 3.0% C, the most optimum edible film can be produced, which has maximum antibacterial activity against E. coli ATCC 25922 (19.36 mm strong) and S. aureus ATCC 25923 (18.94 mm strong). Moreover, this formulation boosts the thickness, tensile strength, and solubility of the film and simultaneously reduces the film's elongation, WVTR, and WVP. The edible bioactive packaging formulation produced thickness, tensile strength, solubility, percentage elongation, WVTR, and WVP values of 0.179 mm, 0.318 Mpa, 0.057%, 10.096%, and 3.747 g/m2.d, 8.586 g/m.d, respectively. The surface of the edible film still had some degree of porosity and texture, according to the morphology
Development of a Problem-Based Learning-Oriented Interactive E-worksheet on Chemical Equilibrium to Enhance Students' Scientific Literacy Skills
Get PDFIndonesian students' scientific literacy scores decreased by 13 points from PISA 2018, indicating that the scientific literacy skills of participants in Indonesia are low. One area of concern is students' understanding of chemical equilibrium, which is essential because it is a prerequisite for grasping subsequent materials. This study aims to assess the feasibility of interactive e-worksheets as a learning medium for chemical equilibrium material in terms of validity, practicality, and effectiveness. According to Thiagarajan, the research employs the 4-D research and development model, which includes Defining, Designing, Developing, and Disseminating but is limited to the development stage. A limited trial was conducted using a one-group pretest-posttest research design. Validation results show that the interactive e-worksheet is valid with a mode value of 4 in content, presentation, language, and design. The validity test results yielded a mode value 4 for both content and construct validity. The practicality test results indicated a high percentage of practicality with very practical criteria. The effectiveness test, analysed using n-gain, showed an n-gain value of 0.78 with high criteria, and the paired sample t-test results indicated a P-value of 0.000, confirming that the post-test scores were significantly higher than the pretest scores. Thus, the PBL-oriented Interactive e-worksheet can improve students' scientific literacy skills
Green Synthesis of SnO2 Nanocrystals Using Garcinia Mangostana L Fruit Peels Extract as Natural Capping Agent
Get PDFThe hydrothermal synthesis of SnO2 nanocrystals at a relatively low-temperature range of 95-100 °C was successfully conducted utilising Garcinia Mangostana L fruit peel extract as a natural capping agent. Characterisation of the synthesised SnO2 nanocrystals was performed using an X-ray diffractometer (XRD) for phase analysis and determination of crystallite size and a Scanning Electron Microscope (SEM) for morphology analysis. XRD analysis revealed the formation of phase-pure SnO2 nanocrystals, with distinct peaks at angles (2θ) of 26.01°, 33.89°, and 51.70° corresponding to miller indices (110), (101), and (211) as per JSPDS standard data. The absence of impurity peaks in the XRD pattern indicated the high purity of the synthesised SnO2 nanocrystals. SEM images exhibited differences in the size and morphology of the synthesised SnO2 nanocrystals with and without the extract. Specifically, the presence of the fruit peel extract led to a reduction in aggregate formation and inhibited crystal growth, resulting in smaller aggregates. These findings highlight the significant impact of Garcinia Mangostana L fruit peel extract on the hydrothermal synthesis of SnO2 nanocrystals with varied sizes and morphologies
Synthesis of Poly Acrylic Acid (PAA) Modified Silver Nanoparticles, Using Trisodium Citrate for Heavy Metal Detection
Get PDFTherefore, this project was to prepare and characterize silver nanoparticles (AgNPs) and study their application for colorimetric detection of heavy metal ions. AgNPs are synthesized by a bottom-up method in which AgNO3 serves as the precursor, which is then reduced using trisodium citrate and stabilized by 1 vol.% polyacrylic acid (PAA). Trisodium citrate facilitates the reduction of Ag+ ions due to its negatively charged carboxylic groups, whereas PAA enhances stability and selectivity. Under the best reaction parameters condition, AgNPs produced brown-yellow colloids with a Surface Plasmon Resonance (SPR) peak of 403 nm. A particle size analysis showed an average particle diameter of 29.9 nm, with a standard deviation σ of 0.482. Fourier Transform Infrared Spectroscopy (FTIR) analysis confirmed that hydroxyl groups -OH and carbonyl groups C=O play a role in reducing Ag+ ions. Because they are highly active, AgNPs can respond to Hg2+ in tests, marking the color change from brown-yellow to transparent white within about one minute. Methods testing for validation of linearity revealed an R2 = 0.9985, and a LOD and LOQ are ca. 0.074 ppm and 0.224 ppm, respectively. At 700 ppm Hg2+, the selectivity was good. These results demonstrate that AgNPs are sensitive and efficient sensors of Hg2+ ions and indicate how to find promising new ways to detect heavy metals in environmental monitoring
Non-Enzymatic Detection of Glucose and Ketones in Urine using Paper-Based Analytical Devices
Get PDFDiabetes, driven by unbalanced diets and unhealthy lifestyles, is highly prevalent. In Indonesia, its prevalence is projected to reach 28.6 million by 2045. Microfluidic paper-based analytical devices (μPADs) are paper-based analytical tools that use hydrophilic paper for measurement and hydrophobic barriers to control fluid flow. This research aims to develop a non-enzymatic method for detecting glucose and ketones in artificial urine using S2Z-μPADs. The fabrication of S2Z-μPADs involves printing the design on Whatman No. 1 paper using wax printing and applying silver nanoparticles for glucose detection and the Schiff base reaction for ketone detection. The results show that the optimum condition for glucose detection is achieved with an AgNO3 concentration of 500 mM. A NaOH concentration of 10 M. Acetoacetate detection is optimized with a glycine concentration of 1 M, sodium nitroprusside concentration of 15%, NaOH concentration of 1 M, a drying time of 8 minutes, and a reaction time of 10 minutes. Validation results demonstrate good linearity for glucose (R² = 0.9821) and ketones (R² = 0.995). High precision was achieved with relative standard deviation (RSD) values of 3.792% for glucose and 1.482% for ketones. The obtained limits of detection (LOD) and limits of quantification (LOQ) indicate that the developed S2Z-μPADs can differentiate between each category of diabetes. The accuracy of glucose and ketone detection ranges from 87.463% to 97.374%. The high accuracy of the μPADs highlights their potential for reliable diabetes management and effective disease monitoring
Functionalization Mesoporous Silica using Aminopropyltriethoxysilane (APTES) as Adsorbent for Removal Ni (II) from Aqueous Solution
Get PDFThis study successfully synthesized mesoporous silica using the template methyl ester ricinoleate (MS-TMR) and further functionalized the MS-TMR surface with 3-aminopropyltriethoxysilane (APTES). The functionalization of MS-TMR with APTES was achieved through a 48-hour grafting method. For the adsorption experiments, 20 mg of both MS-TMR and MS-TMR-APTES adsorbents were employed to remove Ni(II) from aqueous solutions at a concentration of 30 mg/L and pH 6. The objective was to assess the adsorption capacity and to characterize the synthesized adsorbents. Characterization was conducted using Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD). FTIR analysis revealed that the MS-TMR adsorbent possessed silanol (Si-OH) and siloxane (Si-O-Si) groups. Conversely, the MS-TMR-APTES adsorbent exhibited additional amine (N-H) and C-H groups after the APTES grafting. XRD results indicated that both samples were amorphous. The concentration of Ni(II) ions was determined using Atomic Absorption Spectroscopy (AAS), which facilitated the calculation of removal percentages and adsorption capacities. MS-TMR achieved a mere 3.54% removal of Ni(II) ions, corresponding to an adsorption capacity of 3.21 mg/g. In contrast, MS-TMR-APTES demonstrated significantly enhanced performance, removing 54.23% of Ni(II) ions with an adsorption capacity of 48.81 mg/g. The findings suggest that APTES-functionalized MS-TMR has considerable potential for removing Ni(II) ions and could be explored further for the adsorption of other heavy metal ions
Development of a Spreadsheet-Based Virtual Laboratory to Improve Students' Science Process Skills
Get PDFThe media virtual lab was developed with a spreadsheet that displayed 168 electrolysis reactions and performed reaction calculations. The implementation is done to improve the Science Process Skills (SPS) using the power of media. The design is an application of the model Analysis, Design, Development, Implementation, and Evaluation (ADDIE) of Research and Development (R&D). The VL was validated and revised by three media experts, who gave 88 on a score scale and were categorized as the highly qualified assessment of media, material, and visual communication. VL is used more in experimental classes than in control classes and SPS. Both of these classes include descriptions of tests, while SPS description tests generated normal but distributed data with a value of 0,502>0,05. The Levene test with a value of 0.849>0.05 indicates that the data is homogenous. The VL is there is a significant difference because the result of t test value obtained are 0,000<0x7E>0.05. The percentage score of each indicator from the experimental class is compared with the control class, which has a high percentage of each indicator. The farthest difference is the domain for movement manipulation and procedure implementation skills. This lends evidence to the hypothesis test that using VL can augment SPS
The Effect of Voltage on HDPE Microplastic Removal by Electrocoagulation Process Using Stainless Steel Electrode
Get PDFPlastic pollution, especially high-density polyethylene (HDPE), is highly concerned with human health and ecosystems. This study investigates the potential of the electrocoagulation process on the removal of HDPE microplastics from water, evaluating the best operating conditions, including the voltage (4, 8, and 12 V), time (40, 80, and 120 minutes), and pH (3, 5, 7, and 9) to achieve the maximum removal efficiency. Coagulation experiments were conducted in the electrolytic cell, using stainless steel and aluminum electrodes, while Na₂SO₄ served as the electrolyte. Because loss of surface area and change in structure was more evident in fragmented flake and granular microplastics (FTIR and SEM analyses), those microplastics were more retained in the swollen coagulant. The alkaline condition also supports the highest removal efficiency of 96.60% when the pH, voltage, and duration were 9, 8V, and 120 minutes, respectively, as experienced in addition to 0.1g of carbon CTO5 in the study. Conclusions Our findings show that electrocoagulation works best at a medium voltage and in alkaline pH conditions. Under low pH conditions, the removal is not notably influenced by the applied voltage, whereas under neutral and alkaline conditions, removal is significantly enhanced with increased voltage. Moreover, the stainless steel electrodes were more corrosion-resistant than aluminum, thus making the process more sustainable. The results indicate that electrocoagulation represents an environmentally friendly, effective microplastic removal method under the right voltage, time, and pH conditions. Such techniques are an effective strategy that helps reduce water contamination and conserve ecosystems
The Impact of Experimental Research-Based Learning Modules on Students' Affective Domain: A Study on Religious Moderation in Chemistry Education
Get PDFIslamic Religious Colleges (PTKI) 's key mission is to promote religious moderation for students. This aspect is currently missing in the Chemical Education Studies Program curriculum. To address this, we constructed a teaching module that applied the 4S-TMD method (Selection, structuring, characterization, and didactical reduction). This work is based on experimental data of using waste palm coconut shells as activated carbon for methylene blue dye adsorption, which formed two modules: Inorganic Chemistry II (Module A) and Instrumental Analysis Chemistry (Module B). The selection phase was designed with graduate learning outcomes (GLO), learning content, and indicators of religious moderation in module design. The item content validity index (I-CVI), measuring content validity, reached an excellent average of 0.98. During the structuring phase, laboratory experimental results were mapped conceptually. Module A performed excellently, with a validity of 85%, whereas Module B was below 80%. After the refinement steps, both modules reached 100% validity. The measure of the value of religious moderation of GLO indicates >60% for 10 variables, whereas the self-assessment of the nine values of religious moderation of students shows very good (above 20%). This is the first study applying religious moderation to chemistry education and showed that the 4S-TMD method of implementing the 4S-TS method was effective (4.9/5.0 for eligibility). Sow enjoyably integrates chemistry and science education with similar values, which can take place using their type