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"Nanokomposit berbasis biopolimer yang mengalami adsorpsi ion logam pada permukaan bahan pendukung magnetik memiliki kemampuan katalitik lebih baik sehingga menarik untuk dikembangkan sebagai katalis dalam reaksi reduksi 4-nitrofenol. Nanokomposit NaAlg-CMC/Fe3O4 dan NaAlg-CMC/Fe3O4-Cu telah berhasil disintesis yang didukung dengan karakterisasi menggunakan FTIR, XRD dan SEM-EDS Mapping. NaAlg-CMC merupakan biopolimer yang bertindak sebagai support katalis dan dapat membentuk komposit dengan sifat yang baik saat digabungkan dengan Fe3O4. Nanokomposit NaAlg-CMC/Fe3O4 dapat digunakan sebagai adsorben yang baik dalam penghilangan ion Cu2+. Kondisi optimum diperoleh pada berat nanokomposit 50 mg, pH 5,5, rasio NaAlg-CMC/Fe3O4 2:1, waktu kontak 90 menit dengan persen penghilang 97,80% dan kapasitas adsorpsi 48,9018 mg/g. Isoterm adsorpsi ion Cu2+ mengikuti model isoterm adsorpsi Langmuir dengan R2 sebesar 0,9944. Nanokomposit NaAlg-CMC/Fe3O4-Cu dapat menjadi katalis yang baik dalam reduksi katalitik 4-nitrofenol dengan persen reduksi sebesar 92,95 pada berat katalis 45 mg dan waktu reaksi 11 menit. Studi kinetika reaksi reduksi 4-nitrofenol menjadi 4-aminofenol mengikuti kinetika reaksi orde pertama dengan persamaan v = 0,2592 menit-1 [4-NP]. Nanokomposit yang diperoleh dapat menjadi solusi untuk mengurangi logam berat dan polutan organik yang ramah lingkungan.

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Biopolymer-based nanocomposite with adsorbed metal ions on the surface of magnetic support has better catalytic ability that is interest to be developed as a catalyst in the reduction of 4-nitrofenol. SA-CMC/Fe3O4 and SA-CMC/Fe3O4-Cu have been successfully synthesized and supported by characterization using FTIR, XRD and SEM-EDS Mapping. SA-CMC is a biopolymer-based composite as a supporting catalyst and able to form composites with good properties when combined with Fe3O4. SA-CMC/Fe3O4 nanocomposites can be used as good adsorbents of Cu2+ in wastewater. The optimum conditions were obtained by the adsorbent dosage 50 mg, pH 5.5, ratio of SA-CMC/Fe3O4 2:1, contact time 90 minutes with efficiency removal 97.80% and maximum adsorption capacity reached 48,9018 mg/g. The adsorption process of Cu2+ removal follows the Langmuir adsorption isotherm model. SA-CMC/Fe3O4-Cu nanocomposite can be a good catalyst in the reduction of 4-nitrophenol with percent of reduction 92.95% by amount of catalyst 45 mg and reaction time 11 minutes. Study kinetics of reduction 4-nitrophenol to 4-aminophenol follows pseudo-first-order reactions with equation v = 0,2592 min-1 [4-NP]. Nanocomposite can remove heavy metal and organic pollutant in wastewater that are environmentally friendly."

"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."

"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."