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Abstrak :
ABSTRAK
Kolesterol memiliki fungsi fisiologis yang luas dalam tubuh manusia, namun jika konsentrasinya melebihi batas normal maka dapat memicu penyakit seperti arteriosklerosis. Oleh karena itu metode penentuan kolesterol yang cepat dan akurat dikembangkan. Dari semua metode, sensor enzimatik banyak mendapat perhatian, namun sensor ini memilik kekurangan seperti mudah terdenaturasi. Oleh sebab itu penentuan kadar kolesterol menggunakan sensor non-enzimatik saat ini banyak dikembangkan. Perangkat sensor kolesterol non-enzimatik yang dibuat dalam penelitian ini yaitu screen printed electrode SPE yang dideposisi Cu, Ni, dan CuNi yang terhubung dengan potensiostat. Elektrodeposisi Cu, Ni, dan CuNi masing ndash; masing dilakukan pada potensial -0,512 V, -0,326 V, dan -0,804 V dengan variasi waktu deposisi 60 s, 30 s, dan 5 s. Waktu deposisi optimum yang didapatkan yaitu 60 s berdasarkan nilai linearitas, LOD, dan sensitivitas yang didapat dari deteksi kolesterol sistem batch. Cu/SPE, Ni/SPE, CuNi/SPE kemudian diterapkan dalam sistem Flow Injection Analysis FIA . Kinerja sensor optimum diperoleh pada sistem FIA dengan laju alir 0,5 mL/menit dan konsentrasi KOH 1 M. Sensor Cu/SPE, Ni/SPE, dan CuNi/SPE dalam sistem FIA masing ndash; masing memiliki LOD sebesar 1,08, 13,59, 1,24 M dan sensitivitas sebesar 3.584,97, 465,98, 3.258,54 A mM-1 cm-2. Sensor Cu/SPE, Ni/SPE, CuNi/SPE memiliki repeatabilitas yang baik dengan nilai RSD masing ndash; masing 0,68 1,58, dan 1,16. Sensor Cu/SPE, Ni/SPE, CuNi/SPE memiliki reprodusibilitas yang baik dengan nilai RSD masing ndash; masing 0,72, 1,76, dan 0,91. Sensor memiliki stabilitas yang baik yang diukur selama lima hari berturut ndash; turut dengan nilai RSD masing ndash; masing 0,66, 1,54, dan 0,93. Sensor juga selektif terhadap kolesterol dari zat penginterferensi umum yaitu glukosa, sukrosa, fruktosa, asam askorbat, dan NaCl. Cu/SPE, Ni/SPE, dan CuNi/SPE berhasil menentukan kadar kolesterol dalam sampel susu kemasan dan menunjukkan perbedaan hasil 1,88 , 3,59 , dan 3,05 serta recovery 99,79 , 98,61 dan 99,02 berturut ndash; turut.

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ABSTRACT
Cholesterol has a wide physiological function in the human body, but if the concentration exceeds the normal limit it can trigger diseases such as arteriosklerosis. So rapid and accurate method of determining cholesterol is developed. Of all the methods, enzymatic sensors have received much attention, but these sensors have such deficiencies as easily denatured. Therefore, the determination of cholesterol levels using non enzymatic sensors is now widely developed. The non enzymatic cholesterol sensor device made in this study is a screen printed electrode SPE deposited with Cu, Ni, and CuNi connected to a potentiostat. The electrodeposition of Cu, Ni, and CuNi were each performed at a potential of 0.512 V, 0.326 V, and 0.804 V with variations of deposition time of 60 s, 30 s, and 5 s. The optimum deposition time obtained was 60 s based on linearity, LOD, and sensitivity obtained from batch system cholesterol detection. Cu SPE, Ni SPE, CuNi SPE are then applied in the Flow Injection Analysis FIA system. The optimum sensor performance was obtained in FIA system with 0.5 mL min flow rate and KOH concentration of 1 M. Cu SPE, Ni SPE, and CuNi SPE sensors in FIA system each have LOD of 1.08, 13.59, 1.24 M and sensitivity of 3,584.97, 465.98, 3,258.54 A mM 1 cm 2. Cu SPE, Ni SPE, CuNi SPE sensors have good repeatability with RSD values of 0.68 1.58 and 1.16, respectively. Cu SPE, Ni SPE, CuNi SPE sensors have good reproducibility with RSD values of 0.72, 1.76, and 0.91, respectively. The sensors have good stability measured for five consecutive days with RSD values of 0.66, 1.54, and 0.93, respectively. Sensors are also selective against cholesterol from common interfering substances such as glucose, sucrose, fructose, ascorbic acid, and NaCl. Cu SPE, Ni SPE, and CuNi SPE succeeded in determining cholesterol levels in packaging milk samples and showing a difference of 1.88 , 3.59 , and 3.05 and 99.79 , 98.61 And 99.02 respectively.

Abstrak :
Penentuan kadar glukosa menggunakan sensor non-enzimatik pada saat ini banyak dikembangkan sebagai alternatif, sensor glukosa non-enzimatik berupa perangkat yang praktis dan sederhana, digunakan Screen Printed Electrode (SPE) sebagai sensor, kemudian dimodifikasi dengan carbon nanotube (CNT). Pada penelitian ini, digunakan oksida tembaga sebagai sensor non-enzimatik yang terdeposit dipermukaan SPE yang telah diteteskan CNT terfungsionalisasi-OH, dengan metode elektrodeposisi menggunakan larutan CuSO4 0.01M dalam 0,1M H2SO4. Variasi banyak jumlah tetesan CNT terfungsionalisasi-OH, potensial dan waktu deposisi dilakukan untuk mendapatkan deposit Cu/CNT-SPE yang optimum, karakterisasi dengan SEM-EDS. Uji deteksi glukosa dilakukan pada potensial +0.7 V vs Ag/AgCl. Deposit Cu/CNT-SPE dengan 1 tetesan CNT terfungsionalisasi-OH pada potensial -0.65 V selama 300 detik merupakan yang paling optimum, karena mempunyai sensitifitas paling tertinggi sebesar 2514.27 µA mM-1 cm-2, batas deteksi terendah sebesar 0.842 x 10-3 M dan linieritas paling baik sebesar R2 = 0.985. Sensor deposit Cu/CNT-SPE optimum digunakan pada sistem FIA, didapatkan laju alir optimum 0,5 mL/menit, konsentrasi NaOH 1 M sebagai larutan pembawa dilihat dari %RSD sebesar 1.12% rata-rata respon arus 0.000247 A. Pada variasi konsentrasi glukosa dihasilkan linieritas sebesar R2 = 0.982 dengan sensitifitas sebesar 4261.590 µA mM-1 cm-2, batas deteksi terndah sebesar 5.769 x 10-4 M sensor memiliki repeatabilitas yang baik dengan % RSD sebesar 1.52% (n=10). Uji stabilitas selama 5 hari pengamatan dengan %RSD sebesar 1.79%. Deteksi glukosa pada minuman kemasan merk N dengan %KR 13.6%, serta mencari %recovery sampel minunan kemasan merk N didapat 98,36%. Uji interferensi pada glukosa terhadap sukrosa, fruktosa, asam askorbat, asam nitrat dan natrium karbonat. ......Determination of glucose sensor using non-enzymatic sensor has been developed as an alternative to non-enzymatic glucose sensor with practical and simple device, using Screen Printed Electrode (SPE) as sensor, which then modified with carbon nanotube (CNT). In this study, copper oxide are used as non-enzymatic sensor deposited on the surface of SPE dripped with functionalized CNT-OH, using electodeposition method with solution of 0.01 M CuSO4 in 0.1 M H2SO4. Droplets of functionalized CNT-OH, deposition potential and time are varied to find the optimal Cu/CNT-SPE deposit, characterize with SEM-EDS. Glucose detection were tested at the potential of +0.7 V vs Ag/AgCl. The test found that the optimal deposit was Cu/CNT-SPE with 1 droplet of functionalized CNT-OH at potential -0.65 V for 300 seconds, with highest sensitivity of 2514.27 µA mM-1 cm-2, lowest detection limit of 0.842 x 10-3M, and best linearity of R2 = 0.985. The optimal sensor depositition Cu/CNT-SPE electrode were used on flow system FIA, with result of optimal flow rate of 0.5 mL/min, concentration of 1 M NaOH as a carrier seen from %RSD of 1.12% with average current response 0.000247 A. The result of variation of glucose concentration was linearity of R2 = 0.981 with sensitivity 4261.590 µA mM-1 cm-2, lowest detection limit of 5.769 x 10-4M, sensor have good repeatability at %RSD of 1.52% (n=10). Stability test for 5 days resulted in %RSD of 1.79%. Glucose detection in a beverage N yielded %KR of 13.6%, and %recovery of beverage N yielded 98.36%. Interference test on glucose to sucrose, fructose, ascorbic acid, nitric acid and sodium carbonate.

Abstrak :
Perkembangan industri pengolahan limbah elektronik di Indonesia masih sangat minim dan masih menggunakan metode konvensional yang masih tergolong berbahaya bagi lingkungan dan manusia. Seiring dengan berjalannya waktu, dilakukan berbagai penelitian untuk mengatasi masalah tersebut, salah satunya adalah penggunaan larutan asam klorida. Pada penelitian kali ini digunakan sampel Printed Circuit Board untuk melihat perilaku elektrokimia dari logam Cu pada larutan asam klorida dengan konsentrasi 0.1 M, 0.2 M dan 0.5 M dengan menggunakan metode pengujian pelindian, pengujian polarisasi linear dan pengujian Electrochemical Impedance Spectroscopy EIS. Hasil penelitan EIS menunjukan bahwa pengujian PCB-Cu pada larutan asam klorida 0.5 M memiliki diameter kurva semicircle paling kecil diantara larutan asam klorida yang lain. Berdasarkan hasil fitting kurva Nyquist dengan model sirkuit ekuivalen, didapatkan bahwa hasil nilai Rctpaling kecil diantara konsentrasi lain dan lama waktu celup dimiliki oleh larutan asam klorida 0.5 M dengan waktu celup 60 menit yaitu sebesar 0.33 x 103?. Kemudian hasil pengujian polarisasi menunjukan densitas arus dan laju korosi terbesar diantara konsentrasi lain dimiliki oleh larutan asam klorida 0.5 M yaitu sebesar 1.302 A/cm2dan 0.074 mm/year. Hasil ini menunjukan bahwa peningkatan nilai konsentrasi dari larutan asam klorida akan membuat nilai transfer muatan Rct menjadi semakin berkurang, namun meningkatkan densitas arus dan laju korosi dimana hal tersebut menandakan bahwa laju pelindian dari logam Cu pada Printed Circuit Board PCB semakin meningkat seiring dengan peningkatan konsentrasi dari larutan asam klorida.

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The development of electronic waste processing industry in Indonesia is still very minimum and still uses conventional methods that are still classified as dangerous for the environment and human. Over time, various studies were conducted to solve the problem, one of which was the use of hydrochloric acid solution. In this research, experiments are performed using Printed Circuit Board as the sample,to see the electrochemical behaviour of Copper in chloride solution with concentration of 0.1 M, 0.2 M and 0.5 M using leaching, linear polarization and Electrochemical Impedance Spectroscopy EIS method. The result of EIS test shows that the experiment of PCB Cu in 0.5 M chloride solution has the smallest diameter of semicircle curve among other chloride solution.Based on fitting results of Nyquist curve with equivalent circuit model, shows that the smallest Rct value among other concentration and immersion time held by 0.5 M Chloride Solution with 60 minutes of immersion time which is 0.33 x 103, then based on linear polarization test shows that the biggest current density and corrosion rate value among other chloride solution held by 0.5 M Chloride Solution which are 1.302 A cm2and 0.074 mm year. These results shows that with the increase of concentration of chloride solution will decrease the value of charge transfer resistance Rct , but on the other hand will increase the current density and corrosion rate, and can be concluded that recovery rate of Copper from Printed Circuit Board PCB increases along with the increase of concentration of Chloride Soluton.