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A method to determine aceclofenac, ketorolac, and sulindac in human urine samples using microemulsion electrokinetic chromatography (MEEKC) has been developed in this study. The optimization of MEEKC conditions was carried out by changing the microemulsion compositions including the buffer pH, borate salt concentration, surfactant concentration, co-surfactant concentration, organic modifier concentration, and oil droplet concentration. The optimum separation of selected drugs was obtained with a composition of microemulsion containing 10 mM borate buffer pH 9, 0.5% sodium dodecyl sulphate (SDS), 6.6% n-butanol, 6.0% acetonitrile, and 0.8% ethyl acetate. Excellent linearity was obtained in the range concentration of 25 to 200 ppm with r2 > 0.999. Limits of detection (LOD, S/N = 3) and limits of quantification (LOQ, S/N = 10) were 2.72 to 4.75 and 9.08 to 15.85 ppm, respectively. The solid-phase extraction (SPE) method using C-18 as an adsorbent and the solid phase micro-tip extraction (SPMTE) method using multiwalled carbon nanotubes (MWCNTs) as an adsorbent were used to clean-up and pre-concentrate the urine samples prior to the MEEKC analysis. The best recoveries of the selected drugs in the spiked urine sample were 91 to 103% with RSD of 1.26 to 4.03% (n = 3) using the SPE-MEEKC method.

This research report of the synthesis of composite polymers from liquid crystal mesogen reactive (RM82) monomers with Methyl methacrylate (MMA). The purpose of this research is analysis the effect concentration of MMA on the surface and thermal of the composite polymer PMMA-RM82. The result of the morphological analysis of composite surfaces performed by polarization optical microscopy (POM) technique showed liquid crystal textures affected composition from two monomers. SEM images show that the surface of the RM82 liquid crystal has a shape resembling fibrous and blade-like crystals with a length of up to 10 μm (micrometers). Analysis thermal showed the heat released by the PMMA-RM82 increased with the increase in MMA weight percent. This affects the rapid crystallization process of PMMA-RM82 which of concentration MMA 30%-RM82 the heat released is almost twice as much as the heat released by MMA 5%-RM82. The absence of PMMA and RM82 peaks both endothermic and exothermic in PMMA-RM82 samples indicates that polymerization has occurred and a new product has formed. Analysis structure molecule by FTIR found that the IR spectral form of each variation in the weight percent of MMA was almost the same, but there was a spectral shift that showed that polymerization had occurred in PMMA-RM82 which was characterized by a reaction to the free radical C=C bond released by the photoinitiator. XRD pattern of composite PMMA-RM82 showed the peaks formed are located at scattering angles similar to RM82 but there is a decrease in intensity as the percent weight of MMA increases.

Sampah kantong plastik merupakan salah satu penyumbang limbah plastik terbanyak sehingga diperlukan adanya alternatif penggunaan material bioplastik yang mudah terurai oleh lingkungan. Kulit jeruk sebagai sisa hasil pertanian memiliki potensi besar untuk diolah menjadi bahan baku material bioplastik. Material bioplastik berpotensi sebagai alternatif pengganti material yang sulit terurai oleh alam. Pada studi ini, limbah kulit jeruk yang digunakan sebagai bahan baku pembuatan bioplastik, dirancang menjadi tas belanja dengan metode perancangan SCAMPER agar memiliki kualitas dan fungsi yang memadai. Eksplorasi material bioplastik dengan komposisi kulit jeruk, alginat, serat wol, gliserin, dan minyak kelapa masing-masing 19%, 21%, 3%, 47%, 9% dilakukan dengan metode pengeringan alami pada suhu dan kelembaban yang dikondisikan selama 3 hingga 5 hari dan setelah itu hasil material bioplastik dikarakterisasi menggunakan uji mekanik. Bahan bioplastik dari kulit jeruk memiliki ikatan fisik diantara bahan pembentuk dengan kuat tarik, daya beban, elongasi rata-rata, ketahanan robek masing-masing 1,01 N/mm2, 4,0 N, 87,7%, dan 4,1 N. Rancangan tas belanja dari lembaran kulit jeruk ini memiliki ukuran tas 25,5 x 25 cm dengan lebar tas 7,5 cm, warna oranye alami dengan nilai estetika lebih dibandingkan dengan tas belanja konvensional berbahan dasar kain.

Rare Earth Elements (REEs) are strategically important for the industry, especially in the manufacture of high-technology products and components, such as electric batteries for energy storage, energy conversion, defense and security industry, electric vehicles, components on smartphones, laptops, liquid crystal display, and others. Generally, REEs are processed by liquid-liquid extraction. However, this process is very costly due to the use of chemicals and high operational costs, so the waste has the potential to pollute the environment. Currently, innovative separation/recovery techniques are continuously being developed for effective and environmentally friendly extraction of rare earths. The adsorption method using the optimal adsorbent is one of the most efficient methods for recovering REEs at low concentrations. This method offers several advantages, including high release effectiveness, ease of installation and operation, low maintenance costs, and reduced chemical consumption. This study reviews the mechanism, characterization, and several adsorbents from natural to synthetic materials, especially nanocomposite-based adsorbents for the recovery of rare earths. In addition, the discussion of several parameters that affect the adsorbent. However, the results of several methodological breakthroughs that have been carried out show how much further research is needed

Patients with end-stage kidney disease on hemodialysis (ESKD-HD) have a high risk of contracting severe COVID-19. Vaccination can help reduce disease severity, but the immune dysregulation observed in these patients may result in an inadequate antibody response. Therefore, we aimed to evaluate the immune response postvaccination in ESKD-HD patients. This prospective cohort study was conducted in two hemodialysis centers in Indonesia. We enrolled ESKD-HD patients (n = 143) pre- and postvaccination and compared them to healthy subjects (n = 67). SARS-CoV-2 antibody response was assessed using anti-S-RBD antibodies and SVNT % inhibition tests. We performed bivariate and multivariate analysis to determine factors associated with SARS-CoV-2 antibody levels. Seropositive conversion was observed in 97% ESKD-HD subjects postvaccination. Compared with healthy subjects, ESKD-HD patients showed a comparable anti-S-RBD antibody titer postvaccination. mRNA vaccines remained a significant factor for the high immune response, while hypoalbuminemia correlated with lower immune response. In conclusion, ESKD-HD patients showed a robust immune response postvaccination. mRNA vaccines induced a stronger antibody response than other vaccines. Lower levels of serum albumin correlate with lower immune responses in ESKD-HD patients after vaccination.

Ramie fiber is a potential raw material to substitute imported raw materials such as cotton. Due to its higher hemicellulose content, ramie fiber required hydrolysis in a process called degumming. Enzymatic degumming is environmentally friendly compared to traditional process which using chemicals. Alkalithermophilic xylanase have high ability in hemicellulose hydrolysis. The production of xylanase was conducted by submerged fermentation of Bacillus halodurans CM1 in 20L bioreactor using Mamo and corncob medium with optimum conditions at 50°C, pH 9, 150 RPM and 1 vvm. The optimum specific activity of xylanase measured by Bailey method at 70°C and pH 9 is 475.41 U/mg. Xylanase was stable at 50°C, pH 9 and relatively stable to K+, Na2+, Co2+ and Ca2+ metal ions and Triton-X, Saba dan Tween-80 surfactants. Degumming process was carried out by immersing ramie fibers in formulated degumming solution with vlot 1:20 at 50°C, 150 RPM and 180 minutes. The enzymatic degumming process may substitute or reduce the use of chemicals due to its significant effect on ramie fiber quality. Enzymatic and chemical degumming process reduce the weight of Ramie Fiber to 7.23 %, and 7.72 %, slightly higher than enzymatic degumming 7.15%. Enzymatic degumming maintains tensile strength at 27.51 %. Whiteness index enhanced to 2.99% enzymatically and 3.49% chemically. Keywords: Bacillus halodurans CM1, enzymatic degumming, ramie fiber, textile industry, thermoalkaliphilic xylanase