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M. Widyo Wartono
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ALCHEMY Jurnal Penelitian Kimia
ISSN : 14124092     EISSN : 24434183     DOI : -
ALCHEMY Jurnal Penelitian Kimia is a chemistry journal published by Sebelas Maret University, Surakarta. ALCHEMY Jurnal Penelitian Kimia publishes original research articles or review articles in organic chemistry, inorganic chemistry, analytical chemistry, physical chemistry, biochemistry, and environmental chemistry.
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Articles 264 Documents
Profil Kandungan Kimia, Fenolik Total, dan Aktivitas Antioksidan Ekstrak Etanol Tumbuhan Litsea firma (Blume) Hook F Yana Aisya Putri; Rini Muharini; Ira Lestari; Masriani Masriani; Rudiyansyah Rudiyansyah; Antonius R.B. Ola
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 1 (2024): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.1.74158.38-48

Abstract

Litsea firma (Blume) Hook f atau medang piawas merupakan salah satu tumbuhan tingkat tinggi yang dijumpai di Kabupaten Melawi, Kalimantan Barat, Indonesia. Masyarakat setempat memanfaatkannya sebagai obat tradisional untuk menyembuhkan alergi kulit dan menghilangkan bau badan. Penelitian ini bertujuan untuk menentukan profil kandungan kimia, fenolik total, dan aktivitas antioksidan ekstrak akar, batang, dan daun Litsea firma. Analisis fitokimia dan kromatogram reversed phase-high performance liquid chromatography (RP-HPLC) menunjukkan bahwa komponen utama pada setiap ekstrak etanol adalah golongan senyawa fenolik dan cenderung bersifat polar. Kadar fenolik total ditentukan menggunakan metoda Folin-Ciocalteu. Hasil menunjukkan bahwa kadar fenolik total tertinggi adalah ekstrak etanol batang sebesar 90,85 mg GAE/g ekstrak, diikuti ekstrak akar (70,29 mg GAE/g ekstrak) dan daun (51,52 mg GAE/g ekstrak). Penentuan aktivitas antioksidan dilakukan menggunakan 2,2-Diphenyl-1-picrylhydrazyl (DPPH) dengan asam askorbat sebagai kontrol positif. Ekstrak akar, batang, dan daun menunjukkan aktivitas antioksidan moderat dengan IC50 secara berurutan sebesar 134,45 ppm, 112,21 ppm, dan 157,94 ppm,. Dengan demikian, ekstrak batang merupakan sumber senyawa fenolik dan antioksidan yang lebih baik dibandingkan bagian lain tumbuhan L. firma (Blume) Hook f. Characterization of Chemical Composition, Phenolic Content, and Antioxidant Activity of Ethanol Extract from Litsea firma (Blume) Hook F Plants. Litsea firma (Blume) Hook f is one of the higher plants distributed widely in Sungai Pinang Village, Melawi Regency, West Kalimantan, Indonesia. Local people use some parts of the plant as a traditional medicine to cure skin allergies and eliminate body odor. This study aimed to analyze the chemistry profile, measure the phenolic content, and determine the antioxidant activity of Litsea firma roots, stems, and leaf extracts. Phytochemical and reversed phase-high performance liquid chromatography (RV-HPLC) chromatogram analysis on each ethanolic extract showed that each extract possessed a similar phytochemical profile of polar phenolic compounds as major compounds. The Folin-Ciocalteu method was used to determine the total phenolic content using gallic acid as a standard. The results showed that the total phenolic content in the roots, stems, and leaves extract was 70.29, 90.85, and 51.52 mg GAE/g extract, respectively., where phenolic content in the stems was the highest. Antioxidant activity was evaluated using 2,2-Diphenyl-1-picrylhydrazyl (DPPH) with ascorbic acid as a reference standard. The extracts of the roots, stems, and leaves showed moderate antioxidant activity with IC50 values of 134.45 ppm, 112.21 ppm, and 157.94 ppm, respectively. Thus, stem extract Litsea firma Blume has a better antioxidant and phenolic resource from this species.
Studi Bioakumulasi Ion Logam Pb(II) oleh Tumbuhan Mangrove (Sonneratia alba) di Perairan Desa Passo Kota Ambon Abraham Mariwy; Sunarti Sunarti; Cynthia T Tewernussa
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 2 (2024): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.2.74274.267-277

Abstract

ABSTRAK. Jenis partikel dan kandungan Pb pada sedimen, akar dan daun, adalah variabel penting untuk mempelajari akumulasi ion logam Pb(II) oleh tumbuhan mangrove pada perairan Desa Passo Kota Ambon. Jenis partikel sedimen dianalisis menggunakan sieve shaker. Kandungan logam timbal (Pb) pada sedimen, akar dan daun mangrove diukur menggunakan spektrofotometer serapan atom. Kemampuan akumulasi dan translokasi timbal (Pb) pada tumbuhan mangrove (Sonneratia alba) diketahui dari nilai BCF (bioconcentration factor) dan TF (translocation factor). Hasil penelitian menunjukkan bahwa jenis partikel pada stasiun I untuk graval 33,55%, pasir 63,38%, dan lumpur 0,98%, pada stasiun II graval 28,41%, pasir 70,06%, dan lumpur 3,01%, dan stasiun III untuk graval 49,69%, pasir 51,24%, dan lumpur 2,83%. Kandungan logam  timbal (Pb) pada sedimen, akar dan daun di stasiun I secara berturut-turut adalah 41,53; 7,04; dan 2,52 mg/kg; pada stasiun II secara berturut-turut sebesar 44,34; 1,12; dan 3,12 mg/kg; sedangkan pada stasiun III sebesar 43,19; 15,37; dan 20,31 mg/kg. Nilai BCF yang diperoleh pada stasiun I, II, dan III secara berturut-turut yakni 0,22; 0,09; 0,82. Nilai TF pada stasiun I, II, dan III berturut-turut adalah 0,35, 2,78, 1,32. ABSTRACT. (Pb(II) Metal Ions Bioaccumulation Study by Mangrove Plants (Sonneratia alba) in Passo Village Waters Ambon City). Particle types and Pb content in sediments, roots, and leaves are important variables in studying the accumulation of Pb metal by mangrove plants in Passo Village Ambon City waters. Sediment particles were analyzed using a sieve shaker. The content of lead metal (Pb) in sediments, roots, and leaves of mangroves was measured using an atomic absorption spectrophotometer. The ability of lead (Pb) accumulation and translocation in mangrove (Sonneratia alba) plants is known from the BCF (bioconcentration factor)  and TF (translocation factor) values. The results showed that the particle available at station I for gravel 33.55%, sand 63.38%, and mud 0.98%, at station II for gravel 28.41%, sand 70.06%, and mud 3.01 %, and at station III for gravel 49.69%, sand 51.24%, and mud 2.83%. Metal lead (Pb) content in sediments, roots, and leaves in station I were 41.53, 7.04, 2.52 mg /kg, in station II were 44.34, 1.12, 3.12 mg/kg, while in station III were 43.19, 15.37, 20.31 mg/kg, respectively. The BCF values obtained at stations I, II, and III were 0.22, 0.09, and 0.82, respectively. The TF values at stations I, II, and III were 0.35, 2.78, and 1.32, respectively.
Suppressed Ion Chromatographic Analysis of Anionic Macroelements in Nutmeg (Myristica fragrans) Diversity Specific to North Maluku Muhammad Amin; Deasy Liestianty; Abu Rahmat Ibrahim; Nahdiah Amin; Budhi Oktavia
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 1 (2024): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.1.80543.151-161

Abstract

This study proposed an ion chromatography method for analyzing anionic macroelements (fluoride, chloride, nitrite, bromide, nitrate, sulfate, and phosphate), and applied it to nutmeg (Myristica fragrans) diversity to explore the potential of nutmeg as an electrolyte. The analysis method was based on a suppressed conductivity system that simultaneously analyzed the anionic macroelements on Metrohm Supp A 250/4.0 column using 8.0 mM sodium carbonate (Na2CO3) and 0.25 mM sodium bicarbonate (NaHCO3) as a mixture eluent. Excellent peak resolution and completed separation were achieved within 18 min when the flow rate of the detector was 0.8 mL/min. The peak height with calibration curves at 2.5 ‒ 30.0 mg/L concentration ranges was obtained for all anionic macroelements. All collected nutmeg samples were specific to North Maluku. Based on the standard samples used, the analysis results revealed that only four anionic macroelements (chloride, nitrate, sulfate, and phosphate) were found in the nutmeg samples, and the concentration of each anion (e.g., chloride ion, and so) was different for each type of nutmeg. The highest total of anionic macroelements concentration was found in the Myristica succedanea (1605.05 mg/kg) nutmeg sample, while Myristica specioga had the lowest (661.76 mg/kg). The method was validated regarding the detection limit (LOD) and reproducibility.
TiO2-N/Polystyrene photocatalyst-combined Corona Plasma Treatment for Methylene Blue Degradation Kusumandari Kusumandari; Ahmad Qusnudin; Teguh Endah Saraswati; Davit Dhruv
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 1 (2024): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.1.76692.62-69

Abstract

This study employed the corona plasma method combined with TiO2-N/PS photocatalyst to degrade dye pollutants. The plasma reactor consisted of two needle-shaped stainless steel electrodes connected to a voltage of 8 kV. Methylene blue (MB) solution was used as a model pollutant with varied initial concentrations of 10, 50, and 100 ppm. The degradation efficiency was evaluated based on the absorbance of the degraded MB solution measured using a UV-Vis spectrophotometer. The results exhibited that the longer plasma treatment duration caused the absorbance value of the degraded MB to decrease, and then the MB degradation efficiency increased. MB-10 demonstrated a maximum degradation efficiency of 99.40% after plasma treatment for 30 minutes. Meanwhile, MB-50 and MB-100 reached maximum degradation efficiencies of 95.29 and 86.55% efficiency after plasma treatment for 60 minutes. The greater initial MB concentration caused the longer degradation process. Furthermore, the results revealed no increase in degradation efficiency due to the addition of TiO2-N/PS photocatalyst into the plasma treatment. The degradation efficiencies of MB-10, MB-50, and MB-100 under TiO2-N/PS-combined plasma treatment for 30 min were 94.48, 81.57, and 5.22%, respectively. This suggests the possibility that the UV light generated during the plasma process cannot activate the TiO2-N/PS photocatalyst.
Nessler Method Verification for Determining Ammonia in Shrimp Pond Wastewater and Its Application in the Ammonia Adsorption Test with Lampung Natural Zeolite Ni Luh Gede Ratna Juliasih; Lia Madyo Ratri; Andi Setiawan; Mita Rilyanti; Rinawati Rinawati; Agung Abadi Kiswandono; Fitri Kurniawati
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 2 (2024): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.2.72456.257-266

Abstract

Ammonia levels exceeding 0.50 mg/L can threaten organisms in aquatic environments. The Nessler method is one of the ammonia analysis methods based on the reaction between ammonia in a basic solution and Nessler reagent (K2HgI4), forming a colloidal dispersion with a brownish-yellow colour. The colour intensity is determined by spectrophotometry. This research aims to verify the Nessler method for determining ammonia levels in shrimp pond wastewater. The research results indicate that the Nessler method shows good linearity in the range of ammonia concentrations from 1 to 5 mg/L, with a correlation coefficient (R2) value of 0.9962. The precision value was determined from repeatability, expressed as %RSD (Relative Standard Deviation), i.e., 1.92%, and it meets acceptance criteria, which should be less than 0.5 of the Horwitz RSD. The accuracy obtained from the standard addition method provides a percentage recovery value of 99.25%, meeting the AOAC acceptance criteria. The detection limit and quantification limit of the technique are 0.3883 mg/L and 1.2943 mg/L, respectively. The verified method is then applied to analyze shrimp pond wastewater samples from Sriminosari Village, East Lampung, resulting in an ammonia concentration of 1.52 mg/L. The ammonia levels were then reduced by adsorption with natural zeolite Lampung, decreasing ammonia levels by 20.30%. Meanwhile, adsorption with an activated zeolite reduced the ammonia levels by 45.30%.
Preparation and Characterization of Carbon/Si Nanocomposites Synthesized by Chemical Vapor Deposition (CVD) Using SiC and SiO2 Retno Duwi Hardini; Teguh Endah Saraswati; Sentot Budi Rahardjo; Alaa Keshtta
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 2 (2024): September
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.2.80438.218-225

Abstract

Carbon-based nanocomposite materials have attracted the attention of researchers in the last decade due to their unique properties applicable in wide applications. This study aims to synthesize and study the characteristics of the carbon-based nanocomposite material produced using the chemical vapor deposition (CVD) method with SiC and SiO2. The CVD process was carried out at 900 ℃ in a vacuum with flowing argon, hydrogen, and acetylene gases. The CVD process produced nanocomposites with more sp3 hybridized carbon atoms, as indicated by the D peak in the Raman spectra. The diffraction pattern analyses show that the resulting carbon powder nanocomposite growth with SiC powder (CSiC) reveals a carbon diffraction peak C(002) and has an elongated form confirmed by an electron microscope. In comparison, the resulting carbon powder nanocomposite growth with SiO2 powder (CSiO2) has a spherical form and presents a carbon diffraction peak C(002). CSiC nanocomposites showed both symmetric and asymmetric C‒H stretching. In FTIR data, CSiO2 nanocomposites show more intense O‒H group peaks but lower-intensity C‒H group vibrations.
Pengaruh Variasi Konsentrasi Gliserol pada Ekstraksi Glukomanan dari Umbi Porang (Amorphophallus oncophyllus) Triana Kusumaningsih; Melinia Puspita Prahastiwi; Venty Suryanti
ALCHEMY Jurnal Penelitian Kimia Vol 20, No 1 (2024): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.20.1.79438.138-150

Abstract

Kandungan glukomanan yang tinggi pada umbi tanaman porang (Amorphophallus oncophyllus) telah menjadikannya sebagai salah satu sumber glukomanan potensial di Indonesia. Glukomanan yang dikenal dengan kandungan gulanya yang rendah, dapat menjadi makanan pengganti beras yang sehat. Penelitian ini berfokus pada ekstraksi glukomanan menggunakan gliserol, penentuan kadar proksimat, dan penilaian kadar kalsium oksalat dalam glukomanan. Gliserol cairan yang tidak berwarna, tidak berbau, berasa manis, dan tidak beracun, digunakan dalam proses ekstraksi. Ekstraksi glukomanan melibatkan maserasi dengan berbagai konsentrasi gliserol (45, 65, dan 85% v/v). Proses maserasi dilakukan dengan pengadukan pada 12.000 rpm selama 1 jam, diulang dua kali, dan diikuti dengan tiga kali pencucian dengan air suling. Untuk mengurangi kadar kalsium oksalat pada umbi porang, dilakukan perendaman dalam larutan NaCl 10% dan 20% (b/v) pada suhu 80°C selama 30 menit. Konsentrasi gliserol 85% (v/v) memberikan hasil yang optimal untuk ekstraksi glukomanan, menghasilkan glukomanan dengan kandungan 61,2%. Analisis proksimat menunjukkan glukomanan dengan kadar lemak 0,29%; protein 2,33%; karbohidrat 9,41%; air 9,40%; dan abu 2,08%. Konsentrasi NaCl yang paling efektif untuk menurunkan kadar kalsium oksalat adalah 20%, yang menghasilkan penurunan kadar kalsium oksalat sebesar 88,44%. Effect of Glycerol Concentration Variation on Glucomannan Extraction from Porang Tubers (Amorphophallus oncophyllus). Due to the high glucomannan content in its tubers, the porang plant (Amorphophallus oncophyllus) emerges as a potential glucomannan source in Indonesia. Glucomannan, known for its low sugar content, can serve as a healthy rice substitute. This study focuses on glucomannan extraction using glycerol, determining proximate levels, and assessing calcium oxalate levels in glucomannan. Glycerol, a colorless, odorless, sweet-tasting, and non-toxic liquid, was employed in the extraction process. Glucomannan extraction involved maceration with varying glycerol concentrations (45, 65, and 85% v/v). Maceration, accompanied by stirring at 12,000 rpm for 1 hour, was repeated twice, followed by three washes with distilled water. To reduce calcium oxalate levels in porang tubers, soaking using 10% and 20% (w/v) NaCl solution at 80°C for 30 minutes was carried out. An 85% (v/v) glycerol concentration yielded optimal results for glucomannan extraction, producing glucomannan with a content of 61.2%. Proximate analysis indicated glucomannan with 0.29% fat, 2.33% protein, 9.41% carbohydrates, 9.40% water, and 2.08% ash content. The most effective NaCl concentration for reducing calcium oxalate content was 20%, resulting in an 88.44% reduction in calcium oxalate levels
The Characterization of Capsule Shell from Acid-Hydrolyzed Palm Oil Starch Amalia Khairunnisa; Pratika Viogenta; Nani Kartinah; Desy Aulia Azzahra
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 1 (2025): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.1.93550.72-81

Abstract

Acid hydrolysis of palm trunk starch can increase the amylose content in starch, providing a stronger and more stable film. This study aims to obtain the best-modified starch concentration ratio with hydroxypropyl methylcellulose (HPMC) and identify their characteristics. Modifying palm trunk starch was conducted with an acetic buffer using CH3COONa and CH3COOH, decolorizing starch with activated carbon. Manufacturing a capsule shell was performed with weight ratio variations of modified starch and HPMC 1:1 (F1), 2:1 (F2), and 3:1 (F3). All formulations produced firm and elastic capsule shells. The capsule products were consistent in an average weight of F1 (0.10 g), F2 (0.11 g), and F3 (0.14 g). The average disintegration test results were F1 (10 minutes, 27.57 seconds), F2 (6 minutes, 47.06 seconds), and F3 (4 minutes, 34.24 seconds). Tensile strength results were F1 (2.147 MPa), F2 (2.565 MPa), and F3 (2.159 MPa). Fourier Transform Infrared (FTIR) results showed a vibration at a wavenumber of 1560 cm-1 corresponding to the characteristic fingerprint of the C–O vibration stretching in the capsule shell made from starch modified by HPMC. The concentration of modified starch affects the capsule shell’s characteristics, showing that capsule shell F2 (2:1) has the best formulation.
Green-Fuel Production Through Co-Processing Biomass Derived Oil with Standard Gasoil Feedstock Rizki Ekananda; Rokhmaturrokhman Rokhmaturrokhman; Wilda Yuni Parinduri; Zaky Al Fatony
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 1 (2025): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.1.91418.130-137

Abstract

To enhance refinery revenue through the use of new and renewable materials, lab-scale research on green-fuel production has been conducted. This involved co-processing biomass-derived oil with standard gasoil feedstock and existing E-cat to assess its feasibility for commercial fluidized catalytic cracking (FCC) units. The catalytic cracking process varied the type of biomass-derived oil (Crude Palm Oil (CPO) and Refined Bleached Deodorized Palm Oil (RBDPO)) against standard gasoil, using typical operating parameters: cracking temperature of 510 °C, C/O ratio of ~6, and regenerator temperature of 715 °C. The Advanced Cracking Evaluation (ACE) reactor modeled one cycle of reaction and regeneration. Product yields were calculated using mass balance of liquid and gas products, modeled with GC Simdist, GC RGA, and CO2 Analyzer, while gasoline octane number was based on PONA composition using GC DHA. Results showed conversion rates of 85-86%, Research Octane Number (RON) of 91.2 – 93.55, and product yields for coke, dry gas, propylene, LPG, gasoline, LCO, and bottom fraction in the ranges of 6.9 – 7.1%, 1.26 – 3%, 6.79 – 8.5%, 19.52 – 23.1%, 44.8 – 51.63%, 10.21 – 11.4%, and 3 – 3.68%, respectively. Both CPO and RBDPO can be used as co-processing feedstock in FCC units, but adjustments in operating conditions, catalyst formulation, or optimization of the wet gas compressor may be needed due to higher light fraction (Propylene and LPG) and lower gasoline production.
Elektroda Pasta Karbon Termodifikasi Bentonit Alam untuk Analisis Ion Pb(II) dalam Air Laut Irdhawati Irdhawati; Ni Putu Gita Widi Saraswati; Emmy Sahara; Ayu Jyostisya Yotirani Arya Wijana
ALCHEMY Jurnal Penelitian Kimia Vol 21, No 1 (2025): March
Publisher : UNIVERSITAS SEBELAS MARET (UNS)

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20961/alchemy.21.1.80131.82-93

Abstract

Pada penelitian ini, elektroda pasta karbon termodifikasi bentonit alam digunakan untuk analisis ion Pb(II) dengan teknik voltametri pelucutan anodik. Tujuan penelitian ini untuk meningkatkan kepekaan pengukuran ion Pb(II). Parameter yang dioptimasi yaitu konsentrasi bentonit dalam pasta karbon, waktu deposisi, potensial deposisi, serta laju pindai. Rentang konsentrasi linier, limit deteksi, limit kuantisasi, keberulangan, dan persentase perolehan kembali telah divalidasi. Hasil yang diperoleh yaitu konsentrasi optimum bentonit dalam pasta karbon adalah 12%. Waktu deposisi optimum untuk elektroda pasta karbon (EPK) 120 detik, dan 90 detik menggunakan EPK termodifikasi bentonit alam (EPK-B), potensial deposisi optimum yaitu -0,43 V dengan EPK dan -0,23 V dengan EPK-B, serta laju pindai optimum yaitu 15 mV/s dengan EPK dan EPK-B. Hasil validasi pengukuran ion Pb(II) diperoleh konsentrasi linear pada rentang 10 – 1000 μg/L dengan EPK dan 5 – 500 μg/L dengan EPK-B. Limit deteksi dan limit kuantisasi masing-masing pengukuran yaitu 0,08 mg/L dan 0,25 mg/L menggunakan EPK, dan 0,19 mg/L dan 0,64 mg/L menggunakan EPK-B. Keberulangan pengukuran diperoleh nilai lebih kecil dari dua untuk kedua elektroda kerja. EPK-B pada kondisi optimum digunakan untuk menentukan konsentrasi ion Pb(II) dalam sampel air laut, diperoleh hasil 1,47 ± 0,31 mg/L.Carbon Paste Electrode Modified with Natural Bentonite for Analysis of Pb(II) Ion in Seawater. This research used a modified bentonite carbon paste electrode for Pb(II) ion analysis using the anodic stripping voltammetry technique. This research aims to increase the sensitivity of Pb(II) ion measurement. Optimized parameters were the concentration of natural bentonite in carbon paste, deposition time, deposition potential, and scan rate. The range of linear concentration, detection limit, quantitation limit, repeatability, and recovery percentage were validated. The results were obtained the optimum concentration of natural bentonite in carbon paste at 12%. The optimum deposition time with carbon paste electrode (CPE) was 120 seconds and with natural bentonite-modified carbon paste electrode (CPE-B) was 90 seconds, the optimum deposition potential with CPE was -0.43 V, and with CPE-B was -0.23 V, the optimum scan rate for both working electrodes had the same value of 15 mV/s. Pb (II) ion measurements were obtained in the linear concentration range of 10 – 1000 μg/L using CPE and 5 – 500 μg/L using CPE-B. The detection and quantitation limits were found at 0.08 mg/L and 0.25 mg /L for CPE, and 0.19 mg /L and 0.64 mg /L using CPE-B, respectively. The repeated measurements for both CPE and CPE-B produced Horwitz ratio values were less than two. CPE-B at the optimum measurement conditions was used to measure the concentration of Pb (II) ion in seawater sample, found at 1.47 ± 0.31 mg/L.