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"Carbon nanotubes and graphene is a timely second edition of the original Science and Technology of Carbon Nanotubes. Updated to include expanded coverage of the preparation, purification, structural characterization, and common application areas of single- and multi-walled CNT structures, this work compares, contrasts, and, where appropriate, unitizes CNT to graphene. This much expanded second edition reference supports knowledge discovery, production of impactful carbon research, encourages transition between research fields, and aids the formation of emergent applications. New chapters encompass recent developments in the theoretical treatments of electronic and vibrational structures, and magnetic, optical, and electrical solid-state properties, providing a vital base to research. Current and potential applications of both materials, including the prospect for large-scale synthesis of graphene, biological structures, and flexible electronics, are also critically discussed."

"Health and environmental safety of nanomaterials addresses concerns about the impact of nanomaterials on the environment and human health, and examines the safety of specific nanomaterials. Understanding the unique chemical and physical properties of nanostructures has led to many developments in the applications of nanocomposite materials. While these materials have applications in a huge range of areas, their potential for toxicity must be thoroughly understood.Part one introduces the properties of nanomaterials, nanofillers, and nanocomposites, and questions whether they are more toxic than their bulk counterparts. Part two looks at the release and exposure of nanomaterials. The text covers sampling techniques and data analysis methods used to assess nanoparticle exposure, as well as protocols for testing the safety of polymer nanocomposites. It explains characterization techniques of airborne nanoparticles and life cycle assessment of engineered nanomaterials. Part three focuses on the safety of certain nanomaterials, including nanolayered silicates, carbon nanotubes, and metal oxides. In particular, it explores the potential ecotoxicological hazards associated with the different structures of carbon nanotubes and the safe recycling of inorganic and carbon nanoparticles. The final two chapters address the risks of nanomaterials in fire conditions, their thermal degradation, flammability, and toxicity in different fire scenarios."

"Materials science and engineering of carbon : fundamentals provides a comprehensive introduction to carbon, the fourth most abundant element in the universe. The contents are organized into two main parts. Following a brief introduction on the history of carbon materials, Part 1 focuses on the fundamental science on the preparation and characterization of various carbon materials, and Part 2 concentrates on their engineering and applications, including hot areas like energy storage and environmental remediation. The book also includes up-to-date advanced information on such newer carbon-based materials as carbon nanotubes and nanofibers, fullerenes and graphenes."

"Paparan radikal bebas berlebih dapat menimbulkan stres oksidatif yang menyebabkan permasalahan pada kulit. Hal ini umumnya disebabkan akibat paparan sinar UV dan polusi udara. Untuk mengatasi efek buruk akibat radikal bebas, kulit memerlukan antioksidan yang cukup untuk mencegah reaksi oksidasi, salah satunya dengan tokotrienol. Aktivitas antioksidan pada tokotrienol dapat mencegah reaksi oksidasi oleh radikal bebas yang berlebih pada kulit. Penggunaan tokotrienol banyak dimanfaatkan pada kosmetik topikal sebagai antioksidan untuk melindungi kulit. Namun toktorienol memiliki keterbatasan yaitu tidak stabil dikarenakan adanya ikatan rangkap pada rantai samping tokotrienol, sehingga tokotrienol mudah teroksidasi. Akibat dari ketidakstabilan tokotrienol, hal ini dapat menurunkan efektivitas antioksidan dari tokotrienol. Salah satu strategi yang dapat dilakukan untuk menjaga stabilitas tokotrienol adalah dengan memformulasikan tokotrienol kedalam Nanostructured lipid carriers (NLC). NLC terdiri atas campuran lipid padat dan lipid cair dengan penambahan surfaktan. Matriks campuran lipid pada NLC mampu melindungi tokotrienol dari pengaruh luar sehingga tetap tarjaga stabilitasnya. Tujuan penulisan artikel ini adalah mengkaji lebih dalam mengenai nanokosmetik tokotrienol sebagai antioksidan untuk kulit dengan penghantaran NLC untuk menjaga stabilitas tokotrienol. NLC salah satu bentuk nanokosmetik yang berpotensi diaplikasikan sebagai sistem penghantaran kosmetik  yang dapat menjaga stabilitas zat aktif.

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Exposure to excessive free radicals can cause oxidative stress which leads to problems on the skin. Often time this is caused by UV rays exposure and air pollution. In order to prevent oxidative stress the skin needs enough antioxidants, one of which is tocotrienol. Commercial industry, especially cosmetics, often uses tocotrienol for topical application on the skin. However, because of the double bonds on its side chain, tocotrienol is not a stable compound, making it easily oxidized. The unstable structure of tocotrienol can reduce the antioxidants effect, which is the essential feature of tocotrienol. One strategy that can maintain the stability of tocotrienol is combining it with Nanostructured Lipid Carriers (NLC). NLC is a delivery system molecule made from a mixture of solid lipids and liquid lipids with the addition of surfactants. NLC can protect the tocotrienol in the lipid matrix from external influences so that the stability is maintained. The purpose of writing this article is to examine more deeply about the nanocosmetic of tocotrienol as antioxidants for the skin by delivering NLC to maintain stability of tocotrienol.

NLC is a form of nanocosmetics that has the potential to be applied as a cosmetic delivery system that can maintain the stability of active substances.

 

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"Glimepirid merupakan salah satu obat yang termasuk dalam sistem klasifikasi biofarmasetika kelas II dengan kelarutan yang rendah sehingga disolusi rendah. Penelitian ini bertujuan untuk membuat nanostructured lipid carrier (NLC) yang berpotensi meningkatkan disolusi dengan glimepirid sebagai zat aktif dan ditujukan untuk pemberian melalui oral. Pada penelitian ini dibuat tiga formula NLC yang mengandung asam stearat sebagai lipid, minyak zaitun sebagai minyak, sukrosa laurat L-1695 dan sorbitan monostearat sebagai surfaktan dengan perbandingan lipid:minyak 5:5; 7:3; 8:2 secara berturut-turut untuk formula A, B dan C. Pembuatan NLC dilakukan dengan metode homogenisasi panas menggunakan homogenizer bühler dengan kecepatan 15000 rpm selama 20 menit dan sonikasi selama 2 menit. Lalu dilakukan karakterisasi yang meliputi ukuran partikel, indeks polidispersitas dan potensial zeta, morfologi, penetapan kadar, efisiensi penjerapan, uji pelepasan obat dengan membran dialisis, serta uji stabilitas. Seluruh formula NLC glimepirid yang diperoleh berwarna putih dengan ukuran partikel 294-515 nm. Potensial zeta ketiga formula NLC glimepirid memiliki nilai -31,5 hingga -35,2 mV dan indeks polidispersitas 0,406-0,433. NLC glimepirid dievaluasi dengan Transmission Electron Microscopy (TEM) dan tampak memiliki bentuk elipsoid. Kadar glimeprid dalam ketiga formula NLC 95,88-96,84% (b/b). Efisiensi penjerapan formula pada seluruhh formula 75,96-78,78% (b/b). Kumulatif pelepasan obat ketiga formula NLC glimepirid 1,56-1,62 kali lebih tinggi bila dibandingkan dengan glimepirid dan berdasarkan uji ANOVA terdapat perbedaan yang signifikan (p<0,05). Hasil uji stabilitas menunjukkan penurunan kestabilan seiring dengan berjalannya waktu. Berdasarkan hasil yang didapatkan ketiga formula NLC Glimepirid dapat digunakan untuk administrasi oral dan memiliki disolusi yang lebih tinggi dibandingkan glimepirid murni.

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Glimepiride is one of the drugs classified in class two biopharmaceutical classification system with low solubility and low dissolution. The aim of the present study was to prepare glimepiride loaded nanostructured lipid carrier (NLC) that suitable for oral administration and could improve dissolution. In this research, three NLC formulas were made of stearic acid as lipid, olive oil as oil, sucrose laurate L-1695 and sorbitan monostearate as surfactant with ratio oil:lipid 5:5; 7:3 and 8:2 for formula A, B and C. NLC was prepared by hot homogenization with bühler homogenizer 15000 rpm for 20 minutes and sonication for 2 minutes. The result was characterized for its particle size, polydispersity index, zeta potential, morphology, drug content, entrapment efficiency, drug release test by using dialysis membrane, and stability test. The entire NLC glimepiride formula obtained has white color with particle size 294-515 nm. Zeta potential for all formula were -31,5 to -35,2 mV and polydispersity index 0,406-0433. Morphology particle evaluated with Transmission Electron Microscopy (TEM) and the result showed NLC glimepiride has ellipsoid shape. Drug content for NLC glimepiride for all formula were 95,88-96,84% (w/w) and entrapment efficiency were 75,96-78,78% (w/w). NLC Glimepiride showed cumulative drug release 1,56-1,62 higher than glimepiride and one way ANOVA test showed significant difference between NLC glimepiride and glimepiride (p<0,05). Stability study of NLC glimepiride formula showed a decrease in stability over time. In conclusion, NLC Glimepiride could be used for oral administration and showed higher dissolution than pure glimepiride. "

"Nanostructured Lipid Carrier NLc adalah teknologi baru dari jenis nanoemulsi yang dapat meningkatkan bioavaibilitas zat aktif yang bersifat non polar. Jahe putih Zingiber officinale Rosc adalah tanaman obat yang efektif sebagai anti-toksoplasma secara in vitro dengan kandungan senyawa aktif utamanya gingerol yang bersifat semi polar. Jahe merah Zingiber officinale Roscoe var. Rubrum adalah varian jahe yang memiliki kandungan zat aktif gingerol lebih tinggi dibandingkan jahe putih sehingga berpeluang memiliki aktivitas anti-toksoplasma yang lebih baik. Untuk meningkatkan efektivitasnya secara in vivo, perlu pengembangan formulasi ekstrak jahe menjadi bentuk NLc.Tujuan penelitian ini adalah memperoleh metoda ekstraksi untuk mendapatkan ekstrak jahe merah yang paling efektif secara in vitro terhadap T.gondii stadium takhizoit, memperoleh formula NLc-ekstrak jahe merah dengan karakteristik terbaik dan mendapatkan data in vivo aktivitas anti-toksoplasma pada stadium takhizoit dari NLc-ekstrak jahe merah yang terbaik.Metoda yang dilakukan mencakup skrining ekstraksi jahe merah dengan dua jenis ekstraksi dan tiga jenis pelarut pengekstrasi terhadap efektivitasnya pada sel vero yang diinduksi takhizoit in vitro . Ekstrak yang paling efektif diformulasikan menjadi bentuk NLc dengan variasi konsentrasi fase lipid dan fase air, dan komposisi jenis lipid cair dan lipid padatnya. Pembentukan NLc dilakukan dengan metoda High Pressure Homogenizer tekanan 450 bar dengan variasi jumlah siklus. Evaluasi NLc meliputi distribusi dan ukuran partikel, potensial zeta, efisiensi penjerapan, analisa morfologi bentuk partikel dan uji stabilitas pada formula NLc-jahe merah yang paling baik. Tahapan selanjutnya adalah uji in vivo mencakup uji toksisitas akut dan uji efektivitas menggunakan hewan mencit yang diinduksi takhizoit secara intraperitonial.Hasil menunjukkan bahwa metoda ekstraksi yang terbaik adalah metoda maserasi dengan pelarut etanol 96 menghasilkan ekstrak JE96M yang dapat menghambat pertumbuhan takhizoit yang tinggi pada sel vero. Formula NLc-ekstrak jahe merah yang terbaik adalah F7A dengan komposisi minyak sawit:minyak zaitun:lipoid S75 = 14:5,5:5,5 fase lipid 25 dan kadar ekstrak jahe merah 2 . Formula NLc ndash;ekstrak jahe merah F7A pada dosis 100-200mg/kgbb secara peroral efektif sebagai anti-toksoplasma pada mencit, mampu meningkatkan umur hidup mencit diatas 70 setelah diinduksi dengan takhizoit.

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Nanostructured Lipid Carrier NLc is a new technology of the nanoemulsion type. The advantage of NLc is to increase the bioavailability of non polar active substances. White ginger / big ginger Zingiber officinale Roscoe is a medicinal plant that proves effective as an in vitro anti-toxoplasma. This plant has bioactive compounds named gingerols that are semi-polar. Red ginger Zingiber officinale Rosc var Rubrum is another variant of ginger that contains a higher content of gingerols compared to white ginger/big ginger so, therefore it is used in this study to increase the activity of anti-toxoplasma. In order to enhance its effectiveness for in vivo study, the ginger extract is formulated into NLc form that is become the background of this research. The purpose of this study is to obtain the extraction method and to obtain the most effective red ginger extract in vitro on T. gondii takhizoit stage, to obtain the red ginger NLc-extract formula with the best characteristics, and to obtain of anti-toxoplasma activity at the tachizoite stage of NLc-the best red ginger extract. The methods include red ginger extraction screening with two types of extraction process and three types of extracting solvents. Furthermore, the extract tested the effectiveness on tachizoite in vitro using vero cells that induced a tachizoite strain of RH. The most effective extracts were formulated into NLc forms with variations in lipid and water phase concentrations, and the compositions of the liquid lipids and lipids. Formation of NLc was done by High-Pressure Homogenizer method of pressure 450 barr with the variation of cycle number. The NLc evaluation includes the distribution and particle size, and zeta potentials performed so determine the most stable NLc-red ginger extract. In addition, the determination of the effectiveness of adsorption, particle shape morphology analysis and stability test on the best red NLc-ginger formula. The next step is the in vivo test including an acute toxicity test and the effectiveness test, using intraperitoneally induced tachizoite mice. The results showed that the most effective extraction method was the maceration method with 96 ethanol because the extract produced JE96M could inhibit the high tachizoite growth in vero cells. The best NLc-red ginger extract formula is F7A with the composition of palm oil: olive oil: lipids S75 = 14: 5,5 : 5,5 25 lipid phase and 2 red ginger extract level. Formula NLc-red ginger extract F7A at a dose of 100-200 mg / kgbb is peroral effective as an anti-toxoplasma in mice, able to increase mice life above 70 after induced by tachizoite."

"Minyak kelapa sawit dan turunannya saat ini tidak banyak dimanfaatkan dalam bidang farmasi terutama sebagai sistem pembawa obat. Palm stearin dan palm kernel merupakan turunan minyak kelapa sawit mengandung lipid yang dapat digunakan dalam formulasi berbasis lipid, salah satunya nanostructured lipid carrier (NLC). Penelitian ini bertujuan untuk mendapatkan komposisi palm stearin-palm kernel yang optimum untuk menghasilkan NLC dengan karakteristik yang sesuai dan memiliki kemampuan penetrasi subkutan yang lebih baik dibandingkan dengan formulasi tanpa NLC. Optimasi pembuatan NLC mengandung linestrenol dilakukan dengan variasi komposisi palm stearin-palm kernel dengan perbandingan 4:6 (F1), 6:4 (F2), dan 5:5 (F3) kemudian NLC linestrenol yang diperoleh diformulasikan dalam gel dan dievaluasi. Karakterisasi dan evaluasi terhadap NLC linestrenol meliputi ukuran partikel, indeks polidispersitas, zeta potensial, efisiensi penjerapan, dan uji penetrasi in vitro. Formula terbaik dihasilkan oleh formula F2 dengan perbandingan palm stearin-palm kernel (6:4) yang menghasilkan ukuran partikel 129,20 ± 2,851 nm; zeta potensial -31,80 ± 2,36 mV; indeks polidispersitas 0,25 ± 0,075; bentuk sferis, efisiensi penjerapan 84,742 ± 0,264 % serta memiliki stabilitas yang baik dalam gel. Pada uji penetrasi in vitro, gel  NLC linestrenol formula 2 (FGN2) menghasilkan pelepasan obat yang terkontrol dengan jumlah kumulatif linestrenol terpenetrasi lebih tinggi dibandingkan formula gel tanpa NLC (FG) yaitu 74236,77 ng/cm2 untuk FGN2 dan 49591,93 ng/cm2 untuk FG. Nilai fluks untuk FGN2 dan FG masing-masing adalah 4008,6 ng.cm-2.jam-1 dan 3940 ng.cm-2.jam-1. Berdasarkan hasil tersebut, dapat disimpulkan bahwa komposisi palm stearin-palm kernel (6:4) menghasilkan NLC dengan kemampuan penetrasi yang lebih baik dan pelepasan obat yang lebih terkontrol dibandingkan dengan formula gel non NLC.

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Palm oil and its derivatives are currently not widely used in the pharmaceutical field particularly for drug delivery systems. Palm stearin and palm kernel oil were derivatives of the palm oil that contained lipid that can be used in lipid-based formulations such as nanostructured lipid carrier (NLC). The main purpose of this study was to develop an optimized ratio of palm stearin and palm kernel oil to obtained NLC with desirable characteristics and better subcutaneous penetration compared with formulation without NLC. NLC containing lynestrenol was optimized with the variation of palm stearin-palm kernel 4:6 (F1), 6:4 (F2), and 5:5 (F3) then NLC obtained were formulated into a gel dosage form. Formulations of NLC lynestrenol were evaluated on its particle size, polydispersity index, zeta potential, encapsulation efficiency, and in vitro penetration test. The best result obtained from formula F2 with ratio palm stearin-palm kernel (6:4) that produced particle size 129.20 ± 2.851 nm; zeta potential -31.80 ± 2.36 mV; polydispersity index 0.25 ± 0.075; spherical shape, entrapment efficiency 84.742 ± 0.264 % and physically stable. According to in vitro penetration test, NLC lynestrenol F2 (FGN2) showed controlled drug release with cumulative penetration of lynestrenol from FGN2 higher compared with lynestrenol gel without NLC (FG), which value of FGN2 was 74236.77 ng/cm2 and FG were 49591.93 ng/cm2. Flux for FGN2 and FG were 4008.6 ng.cm-2.hour-1 and 3940 ng.cm-2.hour-1, respectively. It can be concluded that the ratio of palm stearin:palm kernel (6:4) obtained NLC that had better subcutaneous penetration compared with formulation without NLC. "