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"This book will provide a systematic overview of the existing and emerging O2 sensing technologies in their different modifications, a practical guide to their rational selection and use, and examples of biological applications/case studies, including details on how to set up and conduct such experiments, troubleshoot and interpret the data."

"Senyawa natrium hipoklorit merupakan senyawa umum yang  digunakan sebagai bahan disinfektan pada air keran dan air kolam renang. Pada penelitian ini nanopartikel Silika-MB@GO-NH2 disintesa dan digunakan sebagai  paper based sensor  dengan metode fluoresensi dalam deteksi senyawa NaOCl murni serta sampel air keran, dan air kolam renang yang  diuji dibawah sinar lampu UV-A. Hasil karakterisasi FTIR diamati adanya puncak serapan yang mengindikasikan keberadaan nanopartikel Silika-MMB@GO-NH2. Pengujian Spektroskopi Raman menunjukan puncak D band dan G band dengan rasio yang menandakan keberadaan dari GO-NH2 serta Silika-MB@GO-NH2. Untuk mengetahui panjang gelombang terhadap %R, dilakukan uji dengan UV-DRS pada paper based sensor dengan variasi konsentrasi NaOCl dan dihasilkan sebesar 367.282 nm1 serta pada uji sampel air keran dan air kolam renang sebesar 388.704 nm-1  yang menunjukan bahwa nanopartikel tersebut  mengabsorpsi cahaya pada daerah sinar ultraviolet (UV). Pada pengujian paper based sensor dibawah lampu UV-A menunjukan cahaya hanya sedikit yang berpendar dan menjelaskan respon kurang baik pada paper based sensor. Data optimasi dan kurva kalibrasi linier terhadap uji interferensi logam Cu dengan nilai y = 0.1204x + 0.0385, dan konsentrasi nya sebesar 0.455 mg / L. Pada logam Fe dengan nilai y = 0.0519x + 0.031 dan konsentrasi sebesar 0.597 mg / L. Pada uji interferensi peroksida di air keran sebesar 0.25 mg / L dan dikolam renang sebesar 0.552 mg / L. Pada interferensi senyawa klorida di air keran didapatkan sebesar 420.165 mg / L dan dikolam renang sebesar 422.215 mg / L.

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Sodium hypochlorite (NaOCl) is common compounds used as a disinfectant in aquatic environments, such as tap water and swimming pool water. In this study, Silica-MB@GO-NH2 nanoparticles were synthesized and applied for paper based sensors, based on fluorescence method under UV-A exposure, for the detection of of pure NaOCl, tap water, and swimming pool samples. The results of FTIR characterization  show the absorption peaks showed the formation of Silica-MB@GO-NH2 nanoparticles. Raman spectroscopy result depict the presence of peaks in the D band and G band with a ratio of  which indicating the presence of GO-NH2 and Silica-MB@GO-NH2. To determine the wavelength of %R, a UV-DRS test was carried out on a paper-based sensor with variations in NaOCl concentration and the result was 367,282 nm-1 and the sample test for tap water and swimming pool water was 388,704 nm-1 which depict that it can absorb light in the ultraviolet (UV) region. In testing the paper based sensor under a UV-A lamp, it shows that only a little light glow and explains the poor response to the paper based sensor. Then obtained optimization data and linear calibration curve for the interference test for Cu metal with a value of y = 0.1204x + 0.0385, and its concentration is 0.455 mg / L. The Fe metal with a value of y = 0.0519x + 0.031 with a concentration of 0.597 mg / L. In the peroxide interference test in tap water of 0.25 mg / L and in the swimming pool of 0.552 mg / L. On the interference of chloride compounds in tap water it was obtained at 420,165 mg / L and in the swimming pool at 422.215 mg / L.  "

"In this thesis, Claudia Backes guides the reader through her multidisciplinary research into the non-covalent functionalization of carbon nanotubes in water. Although one of the most remarkable materials of the 21st century, carbon nanotubes often have limited application because of their intrinsically low solubility and polydispersity. The author shows that rational surfactant design is a powerful tool for chemists because it can unmask the key to solubilization and allow us to tailor nanotube surface and optical properties in a fully reversible fashion. Aspects of organic, physical and analytical chemistry, as well as colloidal sciences are covered in this outstanding work which brings us one step closer to exploiting this super-material to its full potential."

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Efavirenz perlu mencapai konsentrasi serum memadai (1-4 µg/mL) karena ketidaksesuaian kadar obat dapat menyebabkan kegagalan terapi atau toksisitas sistem saraf pusat. Terdapat variabilitas yang signifikan dalam respon pasien terhadap pengobatan efavirenz sehingga perlu dilakukan pemantauan terapi obat (PTO) pada pasien yang menerima efavirenz. Oleh karena itu, diperlukan pengembangan metode bioanalisis efavirenz. Sebelumnya telah dikembangkan metode analisis efavirenz dalam dried blood spot (DBS) menggunakan Kromatografi Cair Kinerja Tinggi-Photodiode Array (KCKT-PDA) tanpa menggunakan baku dalam dengan hasil analisis yang kurang baik pada parameter sensitivitas, akurasi dan presisi, serta tidak sesuai dengan panduan bioanalisis terkini. Penelitian ini bertujuan untuk mengembangkan metode analisis efavirenz dalam DBS yang optimal dan tervalidasi menggunakan baku dalam. Preparasi sampel DBS dilakukan menggunakan metode presipitasi protein dengan volume penotolan darah 30 µL, pengeringan selama 2 jam, ekstraksi menggunakan 300 µL metanol, pengocokan dengan vorteks selama 10 detik, sonikasi selama 1 menit, dan sentrifugasi dengan kecepatan 5.000 rpm selama 5 menit. 200 µL supernatan dipipet dan diuapkan dengan aliran gas nitrogen, kemudian direkonstitusi dengan 100 μL fase gerak. Hasil preparasi sampel dianalisis dengan elusi isokratik menggunakan kolom C18 (Sunfire^TM 5 µm; 250 x 4.6 mm) pada suhu 40^oC; fase gerak asetonitril (ACN):dapar fosfat 10 mMol pH 3 (70:30); laju alir 0,8 mL/min; deteksi UV pada 245 nm; dan baku dalam warfarin natrium. Metode ini memperoleh LLOQ 0,1 μg/mL dan menunjukkan linearitas dalam rentang konsentrasi 0,1-30 μg/mL. Metode ini telah terbukti valid sesuai dengan persyaratan yang ditetapkan oleh US Food and Drug Administration (2018) dan European Medicines Agency (2022). Metode ini lebih sensitif serta lebih akurat dan presisi dengan penambahan baku dalam. Metode juga lebih sederhana sehingga membuat aplikasinya pada PTO menjadi lebih mudah dengan memberikan hasil yang tepat untuk mengurangi risiko efek samping dan meningkatkan efektivitas pengobatan.

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Efavirenz needs to reach adequate serum concentrations (1-4 µg/mL) as inconsistencies in drug levels may result in treatment failure or central nervous system toxicity. Significant variability in patient response to efavirenz treatment requires monitoring of drug levels in blood. Therefore, the development of bioanalytical methods for efavirenz is necessary. The previously published method for determining efavirenz in dried blood spot (DBS) using High-Performance Liquid Chromatography-Photodiode Array (HPLC-PDA) did not use any internal standard and showed poor results in terms of sensitivity, accuracy, and precision. It also did not comply with the current bioanalytical guidelines. This study aims to develop an optimum and validated analysis of efavirenz in DBS, utilizing an internal standard. DBS sample preparation used the protein precipitation method with 30 µL blood spotting volume, dried for 2 hours, extracted using 300 µL of methanol, vortexed for 10 seconds, sonicated for 1 minute, and centrifuged at 5000 rpm for 5 minutes. The 200 µL supernatant was pipetted and evaporated using nitrogen gas flow, then reconstituted with 100 µL of mobile phase.  Samples were analyzed with isocratic elution using C18 column (Sunfire TM 5 µm; 250 x 4.6 mm) at 40^oC; mobile phase acetonitrile (ACN):phosphate buffer 10 mM pH 3 (70:30); flow rate of 0.8 mL/min; UV detection at 245 nm; and warfarin as internal standard. This method obtained LLOQ of 0.1 μg/mL and shows linearity within the concentration range of 0.1-30 μg/mL. The method has been validated according to the requirements set by the US Food and Drug Administration (2018) and the European Medicines Agency (2022). This method is more sensitive, accurate, and precise with the addition of an internal standard. This simpler method makes its application for therapeutic drug monitoring (TDM) easier and ensures appropriate results, thereby reducing the risk of side effects and increasing the effectiveness of the treatment.

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"Exciting results are blooming, thanks to a convergence between unprecedented asteroseismic data obtained by the satellites CoRoT and KEPLER, and state-of-the-art models of the internal structure of red giants and of galactic evolution. The pulsation properties now available for thousands of red giants promise to add valuable and independent constraints to current models of structure and evolution of our galaxy. Such a close connection between these domains opens a new very promising gate in our understanding of stars and galaxies. In this book international leaders in the field offer a wide perspective of the recent advancements in, asteroseismology of red giants, models of the atmosphere, internal structure, and evolution of red giants, and stellar population synthesis and models of the Milky Way."