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"The volume concentrates on modern developments encompassing topics in the wide range from G-quadruplexes via DNAzymes, catalysis at the DNA scaffold, and metal-mediated base pairs to peptide nucleic acids (PNAs) being thus of relevance, e.g., for chemistry and nanotechnology but also for molecular biology and (genetic) diagnostics."

"Studi pemanfaatan limbah untuk adsorpsi logam berat banyak menarik perhatian. Pada penelitian ini, selulosa yang berasal dari serat kardus bekas (WCF) dimodifikasi dengan nanokitosan (WCF/NCH) untuk meningkatkan kemampuan adsorpsi ion logam berat. WCF disiapkan dengan penambahan NaOH untuk memisahkan serat dengan material non selulosa. Hasil karakterisasi spektrofotometer FTIR menunjukkan modifikasi WCF dengan nanokitosan berhasil dilakukan dengan kondisi optimum pada 1 kali pencelupan nanokitosan. Hasil modifikasi WCF/NCH mampu mengadsorpsi larutan ion logam Pb(II) dan Cd(II). Kondisi optimum adsorpsi ion logam Pb(II) didapatkan pada pH awal 6,5, dosis adsorben 0,025 g, waktu kontak selama 10 menit, temperatur reaksi 30 ºC serta kapasitas adsorpsi maksimum sebesar 167,19 mg/g. Hasil optimasi ion logam Cd(II) menunjukkan proses adsorpsi berlangsung optimum pada pH awal 7,0, dosis adsorben 0,025 g, waktu kontak 15 menit, temperatur reaksi 30 ºC serta kapasitas adsorpsi maksimum sebesar 15,86 mg/g. Proses adsorpsi pada WCF/NCH untuk ion logam Pb(II) dan Cd(II) mengikuti model isoterm adsorpsi Langmuir. Studi termodinamika pada adsorpsi ion logam Pb(II) menunjukkan nilai energi bebas Gibbs (ΔGo) negatif pada semua temperatur yang diamati mengindikasikan proses adsorpsi berlangsung secara spontan, sedangkan pada adsorpsi ion logam Cd(II) menunjukkan nilai positif yang mengindikasikan proses adsorpsi berlangsung tidak spontan.

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Recent Study of the utilization of wastes as low-cost adsorbent have become attention. In this work, cellulose from waste corrugated board fiber (WCF) was modified with nanochitosan (WCF/NCH) to enhance its ability to adsorb heavy metal ion. WCF was prepared by the addition of NaOH to separate the cellulose fiber with non-cellulose material. Modification of WCF/NCH was characterized by FTIR. Optimum modification process was obtained at 1 layer of nanochitosan. WCF / NCH can be used for adsorption Pb (II) and Cd (II) ion. Optimum condition for adsorption of Pb(II) ion takes place at the initial pH 6.5, 0.025 g adsorbent dose, 10 minutes of contact time, temperature 30 ºC, and the maximum adsorption capacity was 167.19 mg/g. Optimum condition for adsorption of Cd(II) ion occur at initial pH 7, 0.025 g of adsorbent dose, 15 minutes of contact time, temperature 30 oC, and the maximum adsorption capacity was 15.86 mg/g. The process of adsorption for Pb(II) and Cd(II) ion on WCF/NCH follow Langmuir adsorption isotherm model. Thermodynamics studies for adsorption of Pb(II) shows that the adsorption have negative value at any temperatures indicating adsorption process takes place spontaneously, whereas adsorption of Cd(II) ion have positive value indicating adsorption process takes place non-spontaneously."

"Metal ions in the brain are a necessity as well as a poison. The presence of metal ions in the active sites of biological catalysts or metalloproteins and in the biological functioning of nucleic acids is very well documented and they are required for brain activity. On the other hand, metals are very effective in generating oxidative stress. This effect does not only play a role in immunology but also is the root of practically all neurodegenerative disorders by inducing disease via the death of neurons. Managing metal ions in the brain could therefore be an important strategy in the search for therapeutic agents used in the treatment of neurodegenerative diseases. This new title gives an overview to key topics in the area of metal ions in the brain. It focuses on the role of metal ions in neurological systems by describing their advantageous functions as well as their poisonous features. It is therefore of interest for scientists in biochemistry and biophysics, physiology, toxicology as well as for physicians focused on this topic."

"Senyawa kompleks lantanum-perylene telah berhasil disintesis dengan metode Zulys et al (2017). Hasil yang diperoleh berupa padatan berwarna merah-kecoklatan dengan %yield sebesar 56.90%. Studi mengenai kemampuan fluoresensi senyawa kompleks lantanum-perylene sebagai detektor logam berat dipelajari menunjukkan selektivitas terhadap ion logam Cu2+ dan Pb2+ pada pH netral dan pH yang lebih tinggi (pH 12). Adanya penambahan ion logam Cu2+ dan Pb2+ menandakan senyawa kompleks lantanum-perylene merupakan fluorosensor tipe on-off, terlihat dari adanya pemadaman intensitas fluoresensi. Sedangkan pada penambahan ion logam seperti Ni2+, Co2+, dan Cd2+ tidak menunjukkan perubahan yang signifikan pada pH netral maupun pH yang lebih tinggi. Senyawa kompleks lantanum-perylene dapat mendeteksi ion logam Cu2+ pada rentang konsentrasi dari 1x10-4 M hingga 1x10-8M  dan ion logam Pb2+ pada rentang konsentrasi dari 1x10-4 M hingga 1x10-6M.

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Lanthanum-perylene complex compounds has been synthesized by Zulys et al. (2017) method. The results obtained in the form of red-brown powder with the percent yield of 56.90%. The fluorescence properties of lanthanum-perylene complexes as heavy metal detectors showed selectivity to Cu2+ and Pb2+ metal ions at the neutral pH (pH 7) and higher pH (pH 12). The addition of Cu2+ and Pb2+ metal ions resulted in the quenching of fluorescence intensity, which indicates the lanthanum-perylene complex is an on-off fluorosensor. Whereas the addition of metal ions such as Ni2+, Co2+, and Cd2+ does not show any significant change in the neutral or higher pH.  Furthermore, lanthanum-perylene complex was able to detect Cu2+ metal ions in the concentration range from 1x10-4M to 1x10-8M as well as Pb2+ metal ions in the concentration range from 1x10-4M to 1x10-6M."

"Stroke is a major cause of death and disability in the U.S. and worldwide. A variety of pathophysiologic episodes or cellular medications occur following a stroke, and knowledge of these aftermath events can lead to potential therapeutic strategies that may reverse or attenuate stroke injury. Cellular events that occur following stroke include the excessive releases of excitatory amino acids, alterations in the genomic responses, mitochondrial injury producing reactive oxygen and nitrogen species (ROS), and secondary injury, often in the setting of reperfusion."

"Bentonit alam Jambi telah berhasil dimodifikasi menjadi Organoclay melalui proses interkalasi dengan senyawa asam amino Alanin. Sebelum dilakukan sintesis Organoclay, dilakukan proses fraksinasi dan sedimentasi dari bentonit alam Jambi yang bertujuan untuk mendapatkan bentonit yang kaya akan montmorillonite (MMT) dan menghilangkan pengotor yang terkandung di dalam bentonit. Kemudian dilakukan penyeragaman kation bebasnya dengan Na+ menjadi Na- Bentonit. Selanjutnya dengan menggunakan larutan tembaga amin, dilakukan penghitungan nilai Kapasitas Tukar Kation (KTK) dan diperoleh nilai KTK sebesar 35,3 mek/100 gram bentonit. Sintesis Organoclay kemudian dilakukan dengan menginterkalasikan senyawa Alanin ke dalam Na- MMT dengan 2 nilai KTK pada 3 kondisi pH, yaitu pH 4,7, pH isoelektrik Alanin (pH 6), dan pH 7. Hasil dari karakterisasi FTIR menunjukkan bahwa senyawa asam amino Alanin telah berhasil diinterkalasi ke dalam bentonit alam Jambi pada pH isoelektrik dengan munculnya serapan baru pada bilangan gelombang yang berbeda dengan Na- MMT. Organoclay yang telah disintesis kemudian digunakan sebagai adsorben ion logam berat kadmium dan timbal dengan proses optimasi waktu dan konsentrasi adsorpsi. Hasil menunjukkan bahwa Organoclay memiliki daya adsorpsi yang lebih besar terhadap logam berat dibandingkan dengan bentonit alam. Variasi pH interkalasi 4,7 dan 7 menghasilkan Organoclay dengan kemampuan adsorpsi yang lebih rendah dibandingkan Organoclay yang di interkalasi pada pH isoelektrik Alanin.

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Natural Jambi bentonite have been successfully modified into Organoclay through the intercalation process with acid amino compound Alanine. Before the process for the synthesis of Organoclay begins, the process of sedimentation and fractionation conducted on natural Jambi bentonite in order to get the rich inmontmorillonite (MMT) bentonite and removed the contaminer contained in the bentonite. Then the equalization of free cations is done with Na+ (called Nabentonite). Next, using a solution of copper amine, its cation exchange capacity (CEC) determined and the value of CEC acquired was 35,3 meq/100 grams of bentonite. Synthesis of Organoclay then performed by intercalating Alanine into Na-MMT with 2 values of CEC on 3 pH conditions i.e. pH 4,7, the isoelectric pH of Alanine (pH 6), and the pH 7.

The results of the characterization with FTIR indicated that acid amino Alanine compounds has managed to be intercalated into natural Jambi bentonite with the appearance of new absorbance at different wave number from Na- MMT. Organoclay which have been synthesized then used as an adsorbent of heavy metal ions cadmium and lead with the optimization of adsorption time and concentration process.

The results show that Organoclay have better adsorption capacity compared to unmodified natural Jambi bentonite against heavy metal ions. Organoclay synthesized in variated pH conditions (4,7 dan 7) have lower adsorption capacity than the Organoclay that synthesized in isoelectric pH of Alanine."

"Salah satu metode untuk menentukan keberadaan ion logam dalam suatu sampel adalah dengan senyawa pengkelat yang mampu berfluorosensi dalam bentuk kompleksnya. Senyawa ligan pengkelat yang dimanfaatkan dalam penelitian ini adalah ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin. Senyawa ligan tersebut disintesis dengan dua tahap yakni tahap kondensasi Claisen-Schmidt dan tahap penambahan metil hidrazin berlebih. Karakterisasi senyawa ligan yang disintesis dilakukan dengan bantuan instrumentasi seperti spektroskopi FTIR dan NMR. Eksperimen ini bertujuan untuk mempelajari pengaruh konsentrasi ion logam Cu2+ dan Fe3+ yang dikelatkan dengan ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin, terhadap kemampuannya berfluorosensi sebagai senyawa kompleks. Selektivitas ligan dalam mengkelat ion logam-pun dipertimbangkan. Variasi konsentrasi kedua ion logam diurutkan dari 0,001; 0,002; 0,003; 0,004; 0,005; 0,006; 0,007; 0,008; 0,009 dan 0,01 mol L-1, dalam keberadaan 0,01 mol L-1 senyawa ligan. Dari hasil penelitian ini, ditemukan bahwa seiring peningkatan konsentrasi ion Cu2+ pada kompleks Cu-ligan, emisi fluorosensinya semakin meredup, pada panjang gelombang 255 nm. Hal yang sama terjadi pada kompleks Fe-ligan, terjadi peredupan emisi seiring dengan meningkatnya konsentrasi Fe3+ pada kompleks Fe-ligan, di atas konsentrasi Fe3+ 0,028 mol L-1, pada panjang gelombang 509 nm. Pada uji selektivitasnya, tercatat bahwa ligan ligan 2-(1-metil-5-fenil-4,5-dihidro-1H-pirazol-3-yl)piridin lebih senang mengkelat ion Fe3+ dibandingkan Cu2+.

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One of the method to determine the presence of metal ions in a certain sample, is by using a chelating ligand that gives fluorescent emission when forming it?s complex compound. The ligand compound utilized in this experiment is 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine. The organic ligand was synthesized using a two-step reaction: the first step is a Claisen-Schmidt condensation reaction, the second step is the addition of excess methyl hydrazine. Characterization of the ligand synthesized in this experiment, was done by using instruments such as FTIR spectroscopy and NMR. This experiment was to study the effect of Cu2+ and Fe3+ concentrations that were chelatet by 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine ligand, on the fluorescent abilities of their respective complex compounds.

The selectivity of the ligand on chelating the two metal ions, was also taken to account. The concentration of both metal ions were varied from 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009 dan 0.01 mol L-1, in the presence of 0.01 mol L-1 ligand. From the experimental results, it is shown that as the concentration of Cu2+ increased in Cu-ligand complex, the fluorescent emission became dimmer, at wavelength 385 nm. The same thing happened with Fe-ligand complex, the fluroscent emission of Fe-ligand became dimmer as the concentration increased, at wavelength 509 nm. In the selectivity test, it was shown that 2-(1-methyl-5-phenyl-4,5-dihydro-1H-pyrazol-3-yl)pyridine ligand was more favorable to chelate Fe3+ ions instead of Cu2+."

"Paparan logam berat dapat menimbulkan risiko atau dampak buruk bagi kesehatan manusia. Sebagian besar logam berat ini diekskresikan melalui keringat. Pada penelitian ini, disintesis hidrogel poli(2-(dimetilamino)etil metakrilat-ko-N,N-dimetilakrilamida) (P(DMAEMA-ko-DMA)) dengan variasi komposisi monomer melalui reaksi polimerisasi radikal bebas dengan amonium persulfat (APS) sebagai inisiator dan N,N’-metilenbis(akrilamida) (MBA) sebagai agen pengikat silang. Dilakukan karakterisasi FTIR dan uji swelling pada hidrogel hasil sintesis. Diketahui bahwa rasio swelling meningkat seiring dengan peningkatan komposisi monomer DMAEMA pada hidrogel. Hidrogel P(DMAEMA-ko-DMA) menunjukkan responsivitas terhadap pH dan temperatur, ditunjukkan oleh tren penurunan rasio swelling seiring dengan peningkatan pH dan temperatur. Hidrogel kopolimer dengan komposisi DMAEMA terbesar memiliki rasio swelling tertinggi pada rentang pH dan temperatur keringat. Selain itu, hidrogel P(DMAEMA-ko-DMA) dapat digunakan sebagai adsorben ion logam berat Cd(II) dan Pb(II) pada kondisi keringat, baik dalam larutan tunggal maupun multikomponen. Kapasitas adsorpsi ion logam berat Cd(II) > Pb(II), dan kapasitas adsorpsi meningkat seiring dengan penurunan temperatur. Semakin tinggi konsentrasi awal larutan logam berat, semakin banyak ion logam berat yang dapat teradsorpsi.

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Heavy metal exposure may pose risks or adverse effects to human health. Most of these heavy metals are excreted through sweat. In this research, poly(2-(dimethylamino)ethyl methacrylate-co-N,N-dimethylacrylamide) (P(DMAEMA-co-DMA)) hydrogels with variations in monomer composition were synthesized through a free radical polymerization reaction with ammonium persulfate (APS) as the initiator and N,N’-methylenebis(acrylamide) (MBA) as the cross-linking agent. FTIR characterization and swelling ability tests were conducted on the synthesized hydrogels. It was observed that the swelling ratio increased with an increase in the DMAEMA monomer composition in the hydrogel. The P(DMAEMA-co-DMA) hydrogels exhibited responsiveness to pH and temperature, as indicated by a decreasing trend in the swelling ratio with increasing pH and temperature. The copolymer hydrogel with the highest DMAEMA composition showed the highest swelling ratio within the range of sweat pH and temperature. Furthermore, the P(DMAEMA-co-DMA) hydrogel could be utilized as an adsorbent for heavy metal ions Cd(II) and Pb(II) under sweat conditions, both in single and multicomponent solutions. The adsorption capacity for Cd(II) ions was greater than that for Pb(II) ions, in addition, the adsorption capacity increased with a decrease in temperature. The higher the initial concentration of heavy metal solution, the more heavy metal ions can be adsorbed. "

"ABSTRAKSintesis ligan turunan pirazol 2-(1,5-difenil-4,5-dihidro-1H-pirazol-3-yl)piridin telah berhasil dilakukan dengan metode kondensasi Claisen-Schmidt diikuti dengan penambahan fenil hidrazin berlebih dalam medium pelarut etanol. Padatan kuning kemerahan dengan yield sebesar 28,85% kemudian dikarakterisasi menggunakan spektrofotometer UV-Vis, FTIR, dan spektrometer H-NMR. Studi spektroskopi UV-Vis dilakukan untuk mengetahui pembentukan kompleks antara logam lantanida dengan ligan dalam pelarut asetonitril. Uji aplikasi fluoresens dengan spektrofluorometer diamati untuk melihat perubahan intensitas emisi pada penambahan logam La3+ dan Eu3+. Hasil studi dengan spektroskopi UV-Visible menunjukkan pembentukan kompleks [EuL2]3+ dengan perbandingan Eu3+ : L (1:2) terjadi pada panjang gelombang 366 nm, sedangkan kompleks [LaL3]3+ dimana perbandingan La3+ : L (1:3) terjadi pada λmax 342 nm. Analisis fluoresensi menunjukkan ligan memiliki λ eksitasi 257 nm dan 365 nm dengan nilai absorptivitas molar yang cukup besar pada konsetrasi 2x10-5 M. Penambahan logam La3+ menghasilkan efek fluorescence enhancement pada panjang gelombang emisi 355 nm. Sedangkan penambahan Eu3+ menunjukkan efek pemadaman intensitas emisi pada panjang gelombang 340 nm. Studi selektivitas ligan terhadap keberadaan ion Eu3+ dan La3+ secara bersamaan menunjukkan ligan merupakan fluoresensor yang selektif terhadap La3+ pada λ eksitasi dan λ emisi 257 nm dan 356 nm serta terhadap Eu3+ pada λ eksitasi 273 nm dan λ emisi 341 nm

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ABSTRAKSynthesis of pyrazole derivative ligand 2- (1,5-diphenyl-4,5-dihydro-1H-pyrazole-3-yl) pyridine has been successfully carried out by the method of Claisen-Schmidt condensation followed by the excess addition of phenyl hydrazine in ethanol solution. Reddish yellow solid with a 28.85% yield then characterized using FTIR , UV-Visible, and H1-NMR spectroscopy. UV-Visible spectroscopy study was conducted to determine the complex formation between lanthanide ions with ligands. Fluorescence application test with spectrofluorometer was observed in ligand emission intensity change upon addition of La3+ and the Eu3+. The study by UV-Visible spectroscopy show complex formation of [EuL2]3+ with the ratio Eu3+ : L (1:2) occurs at a absorption wavelength of 366 nm, while the complex [LaL3]3+ with the ratio La3+ : L (1:2) occurred at 342 nm in acetonitrile solution. Fluorescence analysis showed ligands have two excitation λ at 257 nm 365 nm with a appreciable molar absorptivity in concentration 2x10-5 M. The addition of La3+ metal lead to the fluorescence enhancement effect on the λem at 355 nm. While the addition of the Eu3+ demonstrates the effect of fluorescence quenching at the λem 340 nm. Ligand selectivity studies of the existence of ion Eu3+ and La3+ simultaneously show selective fluorescence against La3+ occurred at λex and λem 257 nm and 356 nm as well as the Eu3+ occurred at 273 nm and 341 nm respectively."