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"This book edition is an introductory text that spans all steps of biological organization, from the molecular, to the organism level, as well as influences of environmental factors. In response to the enormous progress recently made, especially in theoretical and molecular biophysics, the author has updated the text, integrating new results and developments concerning protein folding and dynamics, molecular aspects of membrane assembly and transport, noise-enhanced processes, and photo-biophysics. The advances made in theoretical biology in the last decade call for a fully new conception of the corresponding sections. Thus, the book provides the background needed for fundamental training in biophysics and, in addition, offers a great deal of advanced biophysical knowledge."

"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+."

"Ligan 1,4-bis-(1-phenyl-5-(pyridin-2-yl)-1H-pyrazol 3- yl)benzena telah berhasil disintesis menggunakan metode kondensasi Claisen-Schmidt. Hasil yang diperoleh berupa padatan oranye kecokelatan dan dikarakterisasi menggunakan spektrofotometer UV-Vis, spektrofotometer inframerah dan spektrometer NMR. Aplikasi ligan ini sebagai fluorosensor untuk ion logam Cd2+ dan Pb2+ dilakukan dengan menggunakan spektrofluorometer. Hasil studi fluoresensi menunjukkan bahwa ligan mempunyai intensitas fluoresensi yang kuat. Hal ini didukung oleh nilai absorptivitas molar (ε) yang besar. Studi spektroskopi UV-Vis pada penambahan ion Cd2+ dan Pb2+ menunjukkan munculnya puncak baru pada daerah panjang gelombang 355-356 nm. Hal ini menunjukkan bahwa terbentuk kompleks antara ion logam (Cd2+ dan Pb2+) dengan ligan 1,4-bis-(1-phenyl-5-(pyridin-2-yl)-1H-pyrazol 3- yl)benzena. Studi aplikasi fluorosensor menunjukkan bahwa ligan ini dapat dijadikan fluorosensor tipe off-on untuk ion Cd2+ karena penambahan ion ini menyebabkan peningkatan intensitas fluoresensi dan fluorosensor tipe on-off untuk ion Pb2+ karena penambahan ion ini menyebabkan penurunan intensitas fluoresensi.

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Ligand 1,4-bis-(1-phenyl-5-(pyridin-2-yl)-1H-pyrazol-3-yl)benzene has been synthesized using Claisen-Schmidt condensation method. The solid orange brown precipitate was characterized by UV-Visible spectrophotometer, Infrared spectrophotometer and NMR spectrometer. The application of this ligand as fluorosensor for Cd2+ and Pb2+ metal ions was studied by using spectrofluorometer. Fluorescence studies indicate that the ligand has a strong fluorescence intensity. This is supported by a large molar absorptivity (ε) value.

UV-Vis spectroscopy studies on the addition of Cd2+ and Pb2+ ions showed the emergence of a new peak at 355-356 nm wavelength region. This indicates that the complexes formed between metal ions (Cd2+ and Pb2+) with 1,4-bis-(1-phenyl-5-(pyridin-2-yl)-1H-pyrazol3-yl)benzene ligand. Application fluorosensor studies showed that these ligands can be used as off-on type fluorosensor for Cd2+ ions due to the addition of these ions causes an enhanced in fluorescence intensity and fluorosensor on-off type for Pb2+ ions due to the addition of these ions causes a quenched in fluorescence intensity."