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This study introduces a small-scale chemistry practicum technique with the concept of acid-base identification, determination of pH with indicators, and neutralization reactions with the concept of titration. The first experiences of teachers and students in small-scale chemistry practicums are revealed. Action research was carried out to introduce small-scale chemistry (SSC) practicum techniques as solutions for minimizing chemical tools and materials, as well as the availability of space for school chemistry practicums. This study involved 26 teacher participants in the initial process of providing experience and 36 student participants involved in the process of organizing practical classes. Quantitative data including teacher responses and student responses to the SSC practicum in the pilot class were collected using a response questionnaire on the activity. Qualitative data were collected through observation, interviews, and documentation. The practicum involves qualitative observations and quantitative calculations. The qualitative aspect relates to the observation of color changes that occur in a mixture of solutions made of acid and base solutions with certain compositions. Teachers get a lot of inspiration in terms of chemistry practicum with less material requirements, as well as modifying the tools used for laboratory activities. The package of tools and materials provided an illustration for them that practicum activities do not have to be carried out in a laboratory room, but can also be practiced in conventional classrooms, and even carried out independently by students at home. Students have a unique experience in the process of counting the number of droplets as it requires careful concentration and observation.

This research describes the synthesis and characterization of a molecularly imprinted polymer (MIP) as a candidate for the transdermal delivery of curcumin. The MIP was synthesized through precipitation polymerization using methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking agent. MIP characterization studies were conducted using SEM-EDX and FTIR spectroscopy to determine the morphology and interaction between curcumin and polymers. The MIP obtained through precipitation polymerization was in the form of a fine powder with a surface morphology resembling a collection of small granules with a uniform shape. The adsorption capacity of the MIP follows the Langmuir adsorption isotherm model, with a maximum capacity of 4.239 mg/g, which is greater than that of the NIP (3.219 mg/g), resulting in an imprinting efficiency of 1.317. The percentage of curcumin released from the MIP after 8 h was 41.26%, which is lower than that from the NIP, at 51.50%. The drug release kinetics study follows the Higuchi model, indicating drug diffusion from the polymer matrix. Imprinting on the MIP can modify drug diffusion from the polymer matrix, resulting in a reduced release rate in the MIP. Therefore, the MIP can be considered a candidate for the controlled transdermal delivery of curcumin. [ABSTRACT FROM AUTHOR]

High levels of urea and creatinine in the blood are a sign of decreased kidney function. To remove these substances from the blood, hemodialysis which utilizes membranes could be used. In this study, a molecularly imprinted membrane (MIM) was synthesized for the selective transport of urea. The synthesis is initiated with the polymerization of eugenol into polyeugenol and then into polyeugenoxy acetate (PA). The PA is then contacted with urea and then used as the functional polymer in the synthesis of MIM with polysulfone as the membrane base, and polyethylene glycol as the cross-linking agent. The result was later analyzed with FTIR and SEM-EDX. The membrane is then used in the transport of urea, creatinine, and vitamin B12 and then compared with the non-imprinted membrane (NIM) performance. By using UV-Vis spectrophotometry, the results showed that the membrane with 10 h heating variation is able to transport more urea and is more selective than NIM; this proves that the urea template on the MIM enables it to recognize urea molecules better than creatinine and vitamin B12. The order of transport from the best results is urea > creatinine > vitamin B12.

The presence of E‐cadherin⋯E‐cadherin interactions in the intercellular space (paracellular pathway) poses a notable limitation in drug delivery across the blood‐brain barrier (BBB). ADTC5 peptide has shown promising results in improving drug delivery across the BBB by modulating E‐cadherin⋯E‐cadherin interactions. However, the study of E‐cadherin⋯ADTC5 amino acid interactions using quantum mechanics approach has not been observed clearly. Herein, we observed the interaction between E‐cadherin⋯ADTC5 amino acids using density functional theory (DFT). Natural bond orbital (NBO), quantum theory of atoms in molecules (QTAIM), and reduced density gradient (RDG) analysis are performed to study the non‐covalent interaction in detail. The Arg55⋯Asp2 shows the strongest interaction between E‐cadherin⋯ADTC5 modulation, indicated by the highest stabilization energy (E(2)), and hydrogen bonding energy (EHB) about 22.04 and −6.90 kcal/mol, respectively. This interaction is dominated by hydrogen bonding. Such advancements could lead to significant improvements in therapeutic strategies for neurodegenerative diseases, where effective drug delivery across the BBB remains a major challenge. [ABSTRACT FROM AUTHOR]

An imprinted polymer has been successfully synthesized using polyeugenol and polyethylene glycol dimethacrylate (PEGDMA) crosslinker for selective adsorption of Fe3+ ions. The synthesized imprinted polymer is milled to obtain a polymer with high adsorption performance. This work aims to determine the effect of milling on ionic imprinted polymer (IIP) and non-ionic imprinted polymer (NIP) as selective adsorbents of Fe3+ ion against competing metal ions. Adsorbent synthesis was carried out by adding polyeugenol with the crosslinking agent ethylene glycol dimethacrylate (EGDMA) in chloroform solvent and with the initiator 2,2'-Azobis(2-methyl propionitrile) (AIBN). IIP and NIP were used as adsorbents in the adsorption selectivity test of Fe3+ on the binary metals Fe3+/Cu2+, Fe3+/Zn2+, Fe3+/Ag+, and Fe3+/Cd2+. SEM (Scanning Electron Microscope) shows a more identical and smaller particle surface morphology in the milled IIP. Surface area analysis using the BET method (Brunauer-Emmett-Teller) showed an increase in the surface area of IIP after milling treatment. The adsorption capacity and selectivity of Fe3+ metal ions on milled IIP were greater than that of IIP. The selectivity of Fe3+ adsorption is greater in the binary metal ion mixture Fe3+/Cu2+ and Fe3+/Zn2+ than in the Fe3+/Cd2+ and Fe3+/Ag+ solutions. [ABSTRACT FROM AUTHOR]

The purpose of this research is to strengthen pedagogical content knowledge (PCK) in designing laboratory activities based on small-scale chemistry approaches. This research is action research involving 60 trainee teachers with stages that include (a) Reflect; (b) Plan; (c) Act; (d) Observe; (e) Reflect (2nd); (f) Plan (2nd). Qualitative data were collected through (a) Questionnaires reflecting on experiences in practicing chemistry learning and responses to the importance of learning, (b) a Portfolio of chemistry practicum design, (c) documentation of the process of carrying out design, implementation, and practicum evaluation activities, (d) field notes, (e) reflection sheet, and (f) Portfolio of follow-up plans. The data is displayed through the R computation system with data pre-processing stages in the teacher's reflection text which includes basic cleaning, case folding, normalization, stemming, and deleting meaningless words. Display data in the form of word clouds, frequency expression diagrams, and tabulations. Descriptive narratives are used to analyze the documentation obtained in the action process. The teacher group demonstrated performance in implementing small-scale practicum activities. Teachers are increasingly skilled in modifying conventional laboratory equipment, minimizing the amount of chemical use, minimizing waste disposal, and increasing efficiency in the duration of practicum implementation. The follow-up plan for this activity includes quality improvement in aspects of (a) skill in using laboratory equipment, (b) understanding of chemical concepts, (c) equipment availability, materials, and work procedures, and (d) implementation of chemistry practicum. [ABSTRACT FROM AUTHOR]

The design of laboratories in many schools does not meet the pedagogical needs of laboratories. Traditional learning methods not only dominate the learning process in the classroom but also practical learning activities. This study aims (1) to depict perceptions on psychosocial aspects that include student cohesiveness, open-endedness, classroom integration, rule clarity, and material environment; (2) to uncover the relationship between laboratory learning environments and the chemistry teachers’ satisfaction of teaching. The research method used a case study. It was carried out on a group of teachers who are members of a working group of high school chemistry teachers in the Jepara Regency, Central Java Province, Indonesia. The sampling method is convenience sampling. The sample used was teachers who were members of a working group of teachers who were active in the study area. The sample consisted of twenty-six chemistry subject teachers consisting of 9 males and 17 females. The research instrument is a questionnaire that includes three parts. Perceptions of expectations and reality are measured through items that include teaching satisfaction and psychosocial aspects which consist of (1) Student Cohesiveness (SC); (2) Open-endedness (OE); (3) Classroom Integration (CI); (4) Rule Clarity (RC); (5) Material Environment (ME). The conditions of perception of expectations and reality have been described by a significant decrease in four scales, namely SC, OE, RC, and ME. The four scale laboratory environments have a significant correlation with teacher satisfaction in teaching chemistry in the laboratory. The aspect of CI did not experience a significant decrease and did not provide a significant correlation with teacher’s teaching satisfaction. Correlation analysis shows that teachers’ satisfaction in teaching is significantly influenced by the learning environment (83.2%), in this case, the greatest influence in the sequence is the rule clarity (83.9%), student cohesiveness (70.3%), material environment (69.8%), open-endedness (65.5%), and classroom integration (38.0%). [ABSTRACT FROM AUTHOR]

An ionic imprinted membrane (IIM) was synthesized using sulfonated polyeugenol, derived from eugenol, as its functional polymer and polysulfone as its base membrane for the selective adsorption of Au(III). This study aims to determine the adsorption of Au(III) metal ions using IIM compared with the non-imprinted membrane (NIM) and to figure out the membrane selectivity towards Au(III) in mixed solutions of Au/Cd, Au/Cu, and Au/Fe. IIM has a pore size of 0.767 μm while the non-imprinted membrane (NIM) has a pore size of 0.853 μm. The best adsorption result was obtained in the variation of the membrane with the addition of 3.84 g of polysulfone that had pores according to the size of Au. The selectivity results of the Au/Cd mixture solution in NIM and IIM were 17.802 and 36.265. In the mixture of Au/Cu, the NIM and IIM selectivity was 2.386 and 6.886, and in the mixed solution of Au/Fe, the selectivity of NIM and IIM was 0 and 8.489. Thus, the selectivity of IIM towards Au is bigger than NIM. [ABSTRACT FROM AUTHOR]