The long-term use of topical hydroquinone as an anti-hyperpigmentation treatment has well-known, unwanted effects. Deoxyarbutin (4-[(tetrahydro-2H-pyran-2-yl)oxy]phenol) is a relatively new tyrosinase inhibitor, with stronger inhibitory potency than hydroquinone, that exhibited decreased cytotoxicity against melanocytes and other cells. This study developed novel nanostructured lipid carriers (NLCs) for improved topical delivery of deoxyarbutin (dArb), leading to improved depigmenting efficacy. dArb is a hydrophobic substance, but it easily degrades in aqueous medium and is thermolabile. Screening and optimisation of the solid lipid, liquid lipid, surfactant, co-surfactant and production methods were performed to choose the optimum particle size and stability for NLCs. One percent dArb NLCs were obtained from a combination of cetyl palmitate (CP) and caprylic/capric tryglicerides (Myr) in 12% total lipids using poloxamer 188 (P-188) and polyethylene glycol (PEG) 400 as a surfactant and co-surfactant, respectively, with a particle diameter of approximately 500 nm and a polydispersity index (PI) <0.4. These NLCs were produced using the simple method of high-shear homogenisation (10,000 rpm, 5 minutes) and ultrasonication (3.5 min). The compatibility between the substances in the formula was evaluated using Fourier Transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The morphology of the NLCs was observed using transmission electron microscopy (TEM). In vitro penetration of dArb NLCs was evaluated and compared to the nanoemulsion (NE) and conventional emulsion (CR) delivery methods across Spangler’s membrane (SS). Delivery improvement was clearly observed, and after 8 h of application, dArb gel-NLCs showed the highest dArb penetration, followed by liquid NLCs, NE, and CR.

Abstract. In this study we propose a digital dermatoscopy method to measure the human skin roughness. By using this method we eliminate the use of silicon replica. Digital dermatoscopy consists of handheld digital microscope, image processing and information extraction of skin roughness level. To reduce the noise due to the variation of reflection factor on the skin we use median filter. Hence, by Fourier transform the skin texture is imaged in terms of 2D frequencyspatial distribution. Skin roughness is determined from its entropy, where the roughness level is proportional to the entropy. Three types of experiment have been performed by evaluating: (i) the skin replicas; (ii) young and elderly skin; and (iii) seven volunteers treated by anti wrinkle cosmetic in three weeks period. We find for the first and second experiment that our system did manage to quantify the roughness, while on the third experiment, six of seven volunteers, the roughness are succeeded to be identified.

No abstract

Betametason 17-valerat merupakan kortikosteroid topikal dengan efek anti-inflamasi yang banyak digunakan dalam pengobatan dermatitis. Senyawa ini memiliki kelarutan yang rendah dalam air dan mudah terurai menjadi betametason 21-valerat dalam suasana asam atau pun basa. Salah satu alternatif untuk meningkatkan stabilitas obat yang mudah terurai adalah membuatnya dalam bentuk mikroemulsi. Penelitian ini bertujuan untuk membuat formulasi mikroemulsi minyak dalam air yang mengandung betametason 17-valerat. Evaluasi mikroemulsi meliputi organoleptik, pH, viskositas, penentuan ukuran globul, uji stabilitas fisik menggunakan sentrifugasi dan metode freeze-thaw, dan penentuan kadar zat aktif yang disimpan pada suhu 40â—¦C dan kelembaban 75%. Formula mikroemulsi M/A yang stabil dihasilkan dari komposisi yang terdiri dari air, isopropil miristat, Tween 80, etanol, dan propilen glikol, PEG 6000 dengan perbandingan 33 : 10 : 36 : 9 : 10 : 2. Mikroemulsi yang dihasilkan berwarna kuning jernih, dengan viskositas sediaan adalah 1193,52 ± 23,42 cPs dan pH adalah 3-4. Tidak ada perubahan yang signifikan dari warna, bau, viskositas dan pH mikroemulsi setelah pengamatan selama 28 hari. Uji freeze-thaw menunjukkan bahwa mikroemulsi stabil selama 6 siklus dan uji sentrifugasi pada 3750 rpm selama 5 jam memperlihatkan tidak adanya pemisahan fasa. Diameter rata-rata dari globul mikroemulsi adalah 18,79 ±1,09 nm. Hasil uji stabilitas dipercepat menunjukkan tidak ada penurunan kadar yang berarti selama penyimpanan 28 hari pada suhu suhu 40â—¦C dan kelembaban 75%. Kadar betametason 17-valerat yang tersisa dalam mikroemulsi adalah 99,96 ± 0,16 μg/mL.Kata kunci : mikroemulsi, betametason 17-valerat, stabilitas.Betamethasone 17-valerate is a topical corticosteroid with anti-inflammatory effects that are widely used in the treatment of dermatitis. This compound has a low solubility in water and degradate into betamethasone 21-valerate in acid or alkaline condition. The aim of this study was to perform formulation of oil in water (o/w) microemulsion system that consist of betamethasone 17-valerate. The evaluations of microemulsion include of organoleptic, pH, viscosity, oil droplet size, physical stability test using centrifugation and freeze-thaw methods and content of active substance during storage at 40°C and RH 75%. The stable O/W microemulsion formula obtained from this study was the formula which consisted of water, isopropyl miristate, Tween 80, ethanol, propylen glycol, PEG 6000 with ratio of 35:10: 36:9:10:2 respectively. The microemulsion was clear and light yellow, the viscosity was 1193.52 ± 23.42 cPs and its pH was 3-4. There was no significant change in color, odor, viscosity and pH of this microemulsion after observation for 28 days. The freeze-thaw test showed that the microemulsion was stable until 6th cycles, and centrifugation test at 3750 rpm for 5 hours showed that there was no phase separation occured. The mean diameters of the microemulsions were 18.79 ± 1.09 nm. The result from accelerated stability test revealed that there was no descent of betametason content after observation for 28 days at 40°C and 75% RH The remaining concentration of betamethasone 17-valerate in microemulsion was 99.96 ± 0.16 μg/mL.Keywords: microemulsion, betametazone 17-valerate, stability.

ABSTRAK Retinil palmitat (RP) merupakan golongan retinioid, yaitu ester vitamin A (Retinol) yang memiliki gugus palmitat pada ujung rantainya. Retinil palmitat banyak digunakan sebagai antioksidan dan anti kerut dalam industri kosmetika. Hal yang perlu diperhatikan dalam formulasi RP yaitu menjaga stabilitas dari panas, cahaya dan oksigen, sehingga perlu dicari sistem yang mampu melindungi RP dari degradasi. Salah satunya dibuat dalam sistem Nanostructured lipid carriers (NLC), sebagaimana diketahui bahwa NLC merupakan sistem penghantaran obat yang bisa meminimalisir degradasi. Tujuan penelitian ini adalah untuk mengembangkan sistem penghantaran NLC untuk meningkatkan stabilitas serta potensi antioksidan dan meningkatkan difusi RP melalui kulit. Bahan-bahan yang digunakan untuk pembuatan NLC dengan metode teknik mikroemulsi yaitu 4% PEG-8 beeswax dan 4% Isopropil miristat sebagai lipid padat dan lipid cair, 13% Polisorbat 80 sebagai surfaktan, dan 10% Sukrosa stearat sebagai kosurfaktan. Karakterisasi yang dilakukan yaitu pengukuran ukuran partikel dan polidisperistas indeks, efisiensi penjerapan, uji difusi dengan Franz diffusion cell, karakterisasi morfologi dengan Transmission electron microscopy (TEM) dan uji aktivitas antioksidan dengan DPPH. NLC-RP memiliki ukuran partikel 65,63±1,09 nm, indeks polidispersitas 0,32±0,07, efisiensi penjerapan 94,55±0,76%, hasil uji difusi tertinggi yaitu pada NLC-RP 52,58±4,37%, diikuti krim NLC-RP 36,36±1,46%, krim RP 18,70±2,13% dan emulsi RP 18,22±1,50%. Uji stabilitas fisika dan kimia NLC-RP disimpan selama 60 hari pada suhu 25°C RH 65% dan 40°C RH 75% menunjukan bahwa tidak ada perubahan pada kondisi tersebut. Dari penelitian ini didapat kesimpulan bahwa NLC-RP mampu menjaga stabilitas retinil palmitat. Sedangkan NLC-RP yang dimasukan kedalam krim mengalami penurunan kadar sebanyak 58,15% pada suhu ruang dan 70,05% pada suhu 40°C serta penurunan potensi antioksidan akibat keberadaan basis krim.Kata kunci: antioksidan, DPPH, nanostructured lipid carrier, retinil palmitatRETINYL PALMITATE NANOSTRUCTURED LIPID CARRIER (NLC) FORMULATION AND ANTIOXIDANT POTENTIAL TEST ABSTRACT Retinyl palmitate (RP), member of retinoid family is an ester of retinol with palmitate functional group at the end of the chain. RP is commonly used as antioxidants and anti-wrinkle component in cosmetic industry. RP instability requires a formulation system which makes it stable against heat, light and oxygen, such as Nanostructured Lipid Carriers (NLC). NLC is known as notable drug delivery system to minimize degradation. The aim of this research is to develop NLC delivery system to improve stability and antioxidant activity and increase RP diffusion through the skin. Materials used in NLC formulation were obtained using microemulsion technique are 4% PEG-8 beeswax and 4% isopropyl myristate as lipids in solid and liquid form, respectively; 13% polysorbate 80 as surfactant and 10% sucrose stearate as cosurfactant. Characterization NLC were evaluated using particle size measurement, polydispersity index, entrapment efficiency, in vitro diffusion testing using Franz diffusion cell, morphological characterization using Transmission Electron Microscopy (TEM) and antioxidant activity using DPPH. Particle size of NLC-RP was 65,63±1,09 nm, polydispersity index of 0,32±0,07, entrapment efficiency of 94,55±0,76%. Penetration result showed liquid NLC-RP difusion the highest 52,58±4,37%, followed by NLC-RP in cream 36,36±1,46%, RP in cream 18,70±2,13% and RP in emulsion 18,22±1,50%. Physical and chemical stability testing NLC-RP were stored for 60 days at 25°C RH 65% and 40°C RH 75%, the results shown there are no changed in these condition. Research results showed NLC-RP is able to maintain stability of RP, meanwhile NLC RP in cream formulation shows 58.15% amount decrease in room temperature and 70.05% amount decrease at 400C, and antioxidant activity decrease due to cream formulation.Keywords: antioxidant, DPPH, nanostructured lipid carrier, retinyl palmitate