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Abstrak :
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.

Abstrak :
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. ......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.

 

Abstrak :
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.

Abstrak :
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.

Abstrak :
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. ......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. 

Abstrak :
Kemajuan pada bidang bioteknologi saat ini telah banyak memanfaatkan protein dan peptida sebagai agen terapeutik untuk berbagai macam penyakit. Salah satu protein peptida terapeutik yaitu kalsitonin salmon yang digunakan untuk mengobati hiperkalsemia pada penderita hiperparatiroid. Namun, dalam penghantarannya kalsitonin salmon masih memiliki kekurangan, seperti mudah terdegradasi oleh enzim pencernaan saat diberikan secara peroral dan ketidaknyamanan saat menggunakan kalsitonin injeksi maupun intranasal. Penghantaran transdermal menjadi salah satu alternatif yang dapat digunakan untuk menghantarkan kalsitonin salmon secara efektif. Pada penghantaran transdermal, kalsitonin salmon memiliki hambatan penetrasi seperti bobot molekul yang besar dan sifatnya yang hidrofilik, sehingga diperlukan formula yang tepat untuk menghantarkan kalsitonin salmon melalui rute transdermal seperti memformulasikannya dalam pembawa Nanostructured Lipid Carrier (NLC). Tujuan penelitian ini adalah untuk menghasilkan sediaan transdermal kalsitonin dalam pembawa NLC yang dapat meningkatkan penetrasi kalsitonin dan memenuhi persyaratan stabilitas. Enam formula NLC (F1-F6) dibuat dengan metode emulsi ganda dengan penguapan. Formula dikarakterisasi pada ukuran partikel, indeks polidispersitas, zeta potensial, efisiensi penjerapan, dan morfologi partikel. Kemudian, NLC kalsitonin salmon diformulasikan dalam pembawa emulgel. Emulgel NLC kalsitonin salmon dilakukan uji penetrasi in vitro dan studi stabilitas. Hasil penelitian ini menunjukan formula NLC rasio 75:25 lipid padat dan lipid cair dengan konsentrasi kalsitonin salmon 0,04% (F3) merupakan formula optimal, dengan karakteristik ukuran partikel 135,6 nm, indeks polidispersitas 0,1, potensial zeta 34,7 mV, efisiensi penjerapan 99,6%, dan morfologi menunjukkan vesikel berbentuk speris. Berdasarkan hasil uji penetrasi, emulgel NLC kalsitonin menghasilkan peningkatan lima kali lipat dibandingkan dengan emulgel kalsitonin non-NLC. Selain itu, studi stabilitas menggambarkan kadar kalsitonin setelah enam bulan masing-masing 46,09-68,59% dan 43,45-60,59% pada kondisi penyimpanan 5º±3ºC dan 25º±2ºC dengan kelembaban relatif 60%±5%. ......Currently advances in biotechnology has been using proteins and peptides as therapeutic agents. One of therapeutics protein peptide is salmon calcitonin that is used to treat hypercalcemia in hyperparathyroid. However, calcitonin still has limitations in its delivery, such as being easily degraded by digestive enzymes when using perorally, and causing discomfort when using injectable or intranasal. Transdermal delivery is one of the alternative methods that can effectively deliver salmon calcitonin. In transdermal delivery, salmon calcitonin has obstacles to penetration such as hydrophilic and large molecular weight, thus an appropriate formula is needed to deliver through the transdermal route such as formulating in a Nanostructured Lipid Carrier (NLC) carrier system. The aim of this study was to produce calcitonin transdermal in NLC system that can increase the penetration and met the stability requirements. Six formulas of calcitonin NLC were prepared by the double emulsion-evaporation method, then all formulas were characterized in terms of particle size, polydispersity index, zeta potential, entrapment efficiency, and morphology. Salmon Calcitonin NLC were then formulated into NLC-based emulgel. Further, in vitro penetration and stability of NLC calcitonin emulgel studies were conducted. The result showed that formula NLC using 75:25 ratio of solid lipid to liquid lipid with 0.04% drug concentration (F3) was optimal, with a particle size of 135.6 nm, an polydispersity index 0.1, the zeta potential of -34.7 mV, entrapment efficiency of 99.6%, and spherical vesicle morphology. According to the percutaneous penetration study, the NLC salmon calcitonin emulgel resulted in a fivefold enhancement compared to the non-NLC salmon calcitonin emulgel. Moreover, the stability study illustrated salmon calcitonin levels after six months were 46.09-60.95% and 43.45-68.59% at storage conditions of 5º±3ºC and 25º±2ºC with relative humidity 60%±5%, respectively.

Abstrak :
Minyak kelapa sawit merupakan salah satu komoditas ekspor utama Indonesia ke berbagai negara. Hasil fraksinasi utama minyak kelapa sawit yaitu palm stearin (fraksi padat) dan palm olein (fraksi cair). Pengembangan penggunaan palm stearin dan palm olein dibidang farmasi perlu dilakukan untuk meningkatkan manfaat dari minyak kelapa sawit, diantaranya dengan pembuatan Nanostructured Lipid Carrier (NLC). Medroksiprogesteron asetat yang merupakan salahsatu obat KB dipilih sebagai zat aktif yang dibuat dalam bentuk NLC, untuk mensukseskan program Keluarga Berencana. Tingkat putus pakai suntik KB 28%. Alasan wanita berhenti menggunakan alat KB diantaranya karena menginginkan metode yang lebih efektif. Hal ini dapat diatasi dengan pemberian secara transdermal. Tetapi dalam pemberian secara transdermal, stratum korneum menjadi barrier terbesar untuk transpor obat ke dalam kulit. Penelitian ini dilakukan untuk meningkatkan penetrasi obat ke dalam kulit dengan pembuatan medroksiprogesteron asetat dalam bentuk NLC. NLC dibuat dengan metode high shear homogenization (HSH) dan ultrasonikasi. Optimasi formula NLC dilakukan dengan membuat 3 variasi komposisi palm stearin : palm olein (7:3); (5:5);(3:7). Berdasarkan hasil optimasi, NLC dengan perbandingan palm stearin : palm olein (7:3) dipilih sebagai formula optimum dengan karakteristik ukuran partikel 110+0,49 nm, zeta potensial -27,53+1,13 mV, indeks polidispersitas 0,13+0,03 dan efisiensi penjerapan 98,39+0,006 %. NLC terpilih dibuat menjadi bentuk sediaan gel, dibandingkan dengan gel non NLC medroksiprogesteron asetat dan diuji secara in vitro menggunakan uji sel difusi franz. Berdasarkan hasil uji in vitro nilai fluks untuk NLC 285,81 ng/cm2.jam dan untuk gel non NLC 119,25 ng/cm2.jam. Jumlah kumulatif medroksiprogesteron asetat terpenetrasi untuk NLC 5461,66+679,1 ng/cm2 sedangkan untuk non NLC 2204,20+333,68 ng/cm2. Lag time untuk NLC 0,34 jam dan non NLC 2,73 jam. Berdasarkan penelitian dapat disimpulkan bahwa NLC medroksiprogesteron asetat mempunyai daya penetrasi lebih besar dibandingkan dengan non NLC medroksiprogesteron asetat. ......Crude palm oil is one of main commodities exported by Indonesia to many countries. The main fractions of palm oil are palm stearin (solid fraction) and palm olein (liquid fraction). The development of palm stearin and palm olein in the pharmaceutical sector needs to be carried out to increase the benefits of palm oil, this includes manufacture of Nanostructured Lipid Carrier (NLC). Medroxyprogesterone acetate, which is one of the injectable contraceptive drugs,was chosen as the active substance in the NLC, for the success of the Family Planning program. The discontinuation rate for KB injections is 28%. Some of the reasons why patients stop using family planning devices are because they want a more effective method. This problem can be treated with transdermal administration. However, in transdermal administration, stratum corneum is the biggest barrier for drug transport into the skin. This research was conducted to increase the penetration of the drug into the skin by forming medroxyprogesterone acetate to an NLC. NLC was made by high shear homogenization (HSH) and ultrasonication methods. The NLC optimization formula performed by making 3 variations of palm stearin composition: palm olein (7:3); (5:5); (3:7). Based on the optimization results, NLC with a ratio of palm stearin : palm olein (7:3) was chosen as the optimum formula with the characteristics of particle size 110+0.49 nm, zeta potential -27.53+1.13 mV, polydispersity index 0.13+0.03 and entrapment efficiency 98.39+0.006 % . The selected NLC was made into a gel dosage form, compared with non-NLC medroxyprogesterone acetate gel and tested in-vitro using the Franz diffusion cell. Based on the in-vitro test results, the flux value for NLC was 285.81 ng/cm2.hour and for non-NLC gel was 119.25 ng/cm2.hour. The cumulative amount of medroxyprogesterone acetate penetrated for NLC was 5461.66 +679.1 ng/cm2 while for non-NLC was 2204.20+333.68 ng/cm2. Lag time for NLC was 0.34 hours and non-NLC was 2.73 hours. Based on the research, it can be concluded that NLC medroxyprogesterone acetate has higher penetration than non NLC medroxyprogesterone acetate.