whatman paper
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2022 ◽  
Vol 951 (1) ◽  
pp. 012057
Author(s):  
N R Yanti ◽  
M Andika ◽  
S Maulida ◽  
Riani ◽  
I Sulaiman ◽  
...  

Abstract Areca nut contains tannin which has a great potential to apply as natural colour agent in food industries. Tannin offers specific colour and alter its colour due to environmental sensitivity. This study aims to fabricate a tannin-based colour indicator from areca nut in smart packaging in the form of a strip type and to characterize the indicator at different storage conditions and at various pH solutions. The indicators were synthesized using filter paper (No.1 and No.42) soaked in a solution with 1, 3, and 5% areca nut ethanolic extract. Then the indicators were stored at room temperature and 4-7°C for 10 days, then their Red Green Blue (RGB) coefficient values were measured. Characterization of the indicators at pH 3-10 were also determined by RGB coefficient. The results showed that the indicator stored at 4-7°C had more stable RGB coefficient than the indicator stored at room temperature indicated the indicator was influenced by the temperature factor. The indicator offered a potential to be used as a sensor on packaging of temperature sensitive foods. The indicator using Whatman paper No.42 with 1% of extract steadily decreased in RGB coefficient and changed its colour to darker in basic pH solution while the indicator with other treatments had unstable alteration RGB coefficient and colour.


2021 ◽  
Vol 7 (4) ◽  
pp. 1-22
Author(s):  
Mukasa Tebandeke I.Z ◽  
Karume I ◽  
Ssebuwufu J ◽  
Wasajja H.Z ◽  
Nankinga R ◽  
...  

Pollution resulting from unsustainable agricultural and urbanization activities in the Ruhezamyenda and Bunyonyi catchments are threatening lake Bunyonyi. These have led to high chemical oxygen demand (COD), electrical conductivity, turbidity, pH, iron (II) concentration and low dissolved oxygen (DO5). In this study we have investigated the how COD, turbidity, pH, concentration of iron, total suspended solids, total nutrients and DO5 of water changed with distance in lake. Water sampled from different distances in the lake filtered using Whatman paper at ambient temperatures was tested for COD, electrical conductivity, turbidity, total nutrients, iron, hardness and DO5. COD was 20.8±.0.03mg/L to 16 ± 0.03mg/L; total hardness was 16.5±0.2 mg/L to 18.6 ± 0.3 mg/L total nitrate was 103.5± 2 mg/L to 88 ± 3 mg/L; total phosphate was 100.8 ±.2.5 to 87± 3 mg/L; high TSS values from 3.4 ± 0.1 mg/L to 2.5 ± 0.1 mg/L showed contamination of water. As pH decreased from 8.3 ± 0.03 to 7.6 ± 0.04 revealed that bases were getting removed. The turbidity dropped from 25.7 ± 0.3 NTU to 20 ± 2 NTU due settling down of sediments. Iron (II) concentration ranging from 1.1± 0.1 to 0.8± 0.1 mgL-1 . Dissolved oxygen decreased from 7.9 ±0.3 mg/L to 4.8 ± 0.2 mg/L indicating surface water can uphold life of aquatic organisms. Total hardness ranged from 0.22± 0.05 to 0.19± 0.05 mg/L Electrical conductivity was high and ranged from 130± 5 to 150± 5 µS/cm indicating presence of electrolytes. Lake Bunyonyi water is not greatly polluted, but requires to be safe guarded against poor unsustainable agricultural practices, sewage draining from towns, schools and hotels in nearby settlements.


2021 ◽  
Vol 18 (2) ◽  
pp. 61
Author(s):  
Dwi Mukti Kusumastuti ◽  
Zainul Cholid ◽  
Winny Adriatmoko

Tooth extraction causes prolonged bleeding complications and the body will respond with hemostasis. Currently developing natural medicines to help the process of hemostasis. Red dragon fruit peel, which is generally a waste containing tannins, flavonoids, and saponins to stop bleeding. Purpose was to find out the effect of red dragon fruit peel extract on bleeding time in the tail of Balb-C strain mice. 16 mice samples were adapted for one week. Mice were divided into 2 groups subsquently fasted for 7 hours. The first group as a control (0.5% Na-CMC). The second group was given red dragon fruit peel extract which was divided into three sub-groups at a dose of 0.5 mg / g BW, mg / g BW, and 1.5 mg / g BW. All samples were waited for 45 minutes and cut along 2 cm from the tip of the tail. Blood is spilled on Whatman paper which has 30 seconds in each box. The number of blood spots on the box was calculated and multiplied by 30 seconds. The result showed that bleeding time in the group given red dragon fruit peel extract was significantly lower (p <0.05) than in the control group. The conclusion was red dragon fruit peel extract (Hylocereus Polyrhizus) has an effect on shortening the bleeding time in cutting the tail of bulb-c strain mice and the dose of red dragon fruit peel extract (Hylocereus Polyrhizus) which has the most significant effect is 1 mg / BB mice.


2021 ◽  
Vol 10 (3) ◽  
pp. 53-59
Author(s):  
Desmagrini Desmagrini ◽  
Awitdrus Awitdrus ◽  
Erman Taer ◽  
Rakhmawati Farma

Abstrak. Karbon aktif yang berasal dari biomassa telah menjadi bahan elektroda paling kompetitif untuk superkapasitor karena sifatnya yang terbarukan dan berkelanjutan. Upaya optimalisasi dilakukan untuk proses pembuatan sel superkapasitor dengan memvariasikan separator agar dapat memperoleh kapasitansi spesifik yang tinggi. Biomassa biji kurma sebagai bahan dasar pembuatan elektroda karbon melalui proses prakarbonisasi, aktivasi kimia dengan aktivator KOH 0,3M, proses karbonisasi dengan suhu 650oC dialiri gas nitrogen. Penyusutan massa karbon sebesar 24,59%. Nilai densitas dari elektroda karbon setelah dilakukan proses karbonisasi adalah 0,852 g cm-3. Analisis struktur mikro menunjukkan bahwa elektroda karbon bersifat amorf ditunjukkan dengan adanya puncak pada sudut 2θ sekitar 24o dan 44o. Kapasitansi spesifik ditentukan dengan metode Cyclic Voltametry dan didapati sebesar 217,22; 176,18; dan 82,8 F/g masing-masing untuk variasi separator kertas whatman, kertas saring, dan membran telur ayam. Hasil penelitian menunjukkan bahwa pada kertas whatman merupakan separator terbaik untuk elektroda karbon dari biji kurma. Oleh karena itu karbon aktif yang dibuat dari biji kurma dengan biaya rendah, ketersedian mudah, dan berkelanjutan dapat diaplikasikan sebagai bahan elektroda untuk superkapasitor.Abstract. Activated carbon derived from biomass has become the most competitive electrode material for supercapacitors due to its renewable and sustainable nature. Optimization efforts are made for the process of making supercapacitor cells by varying the separator in order to obtain a high specific capacitance. Date seed biomass as the basic material for making carbon electrodes through a pre-carbonization process, chemical activation with a KOH activator of 0.3M, the carbonization process at a temperature of 650oC flowed with nitrogen gas. Shrinkage of carbon by 24.59%. The density value of the carbon electrode that was carried out by the carbonization process was 0.852 g.cm-3. The microstructure analysis showed that the carbon electrode was amorphous indicated by the presence of a peak at an angle of 2θ around 24o and 44o. Specific capacitance was determined by the Cyclic Voltametry method and was found to be 217.22, 176.18, and 82.8 F/g respectively for the Whatman paper, filter paper, and chicken egg membrane separator variations. The results showed that whatman paper was the best separator for carbon electrodes from date palm seeds. Therefore, activated carbon made from date seeds with low cost, easy availability, and sustainability can be applied as an electrode material for supercapacitors.Keywords: Date seed, Activated Carbon, Supercapacitor, Carbon Electrode, Separator


2021 ◽  
Vol 10 (3) ◽  
pp. 291-298
Author(s):  
Jusup Suprijanto ◽  
Juwita Lesly Senduk ◽  
Dewi Basthika Makrima

Mikroplastik adalah salah satu pencemar laut. Mikroplastik tidak dapat terdegradasi dengan cepat. Mikroplastik merupakan partikel plastik yang berukuran <5mm. Ukurannya yang kecil menyebabkannya dapat tertransportasikan ke seluruh tempat termasuk sistem tubuh ikan dan cumi-cumi. Penelitian dilakukan bertujuan mengetahui mikroplastik pada cumi – cumi (Loligo sp.) dan ikan kembung (Rastrelliger sp.). Penelitian dilakukan bulan Juli 2020 – November 2020 di Semarang Jawa Tengah. Pengambilan sampel dilakukan di TPI Tambak Lorok Semarang.  Pengukuran cumi-cumi dilakukan menggunakan jangka sorong dan ikan diukur menggunakan penggaris. Pembedahan cumi-cumi dan ikan dilakukan menggunakan gunting bedah untuk memisahkan alat pencernaan, tentakel serta insang ikan yang akan digunakan sebagai sampel. Pelarutan dilakukan menggunakan perendaman KOH 10% selama 24 jam untuk melarutkan bahan organik. Pemisahan partikel mikroplastik dilakukan setelah seluruh bahan organik pada sampel larut seluruhnya. Pemisahan partikel mikroplastik dilakukan menggunakan perendaman ZnCl2 selama 24 jam. Penyaringan sampel dilakukan setelah sampel mempunyai 2 layer, layer pertama diambil 10 ml kemudian disaring menggunakan kertas whatman dengan vacump pump. Sampel yang telah disaring dikeringkan, dilanjutkan uji FTIR. Hasil penelitian menunjukkan bahwa terdapat mikroplastik dalam cumi – cumi dan ikan kembung yang ada di TPI Tambak Lorok Semarang, FTIR menunjukkan terdapat polimer plastik jenis nitrile dan nylon. Microplastic is one of the pollutants of the sea. Microplastics do not degrade quickly. Microplastics are plastic particles <5mm in size. Its small size allows it to be transported all over the place including the body systems of fish and squid. The research was conducted to determine the microplastics in squid (Loligo sp.) And mackerel fish (Rastrelliger sp.). The research was conducted in July 2020 - November 2020 in Semarang, Central Java. Sampling was carried out at TPI Tambak Lorok Semarang. Measurements of squid were carried out using a caliper and fish were measured using a ruler. Squid and fish surgery is performed using surgical scissors to separate the digestive organs, tentacles and fish gills that will be used as samples. Dissolving was carried out using 10% KOH immersion for 24 hours to dissolve organic matter. The separation of microplastic particles is carried out after all the organic material in the sample is completely dissolved. The separation of microplastic particles was carried out using ZnCl2 immersion for 24 hours. Filtering of the sample is carried out after the sample has 2 layers, 10 ml of the first layer is taken then filtered using Whatman paper with a vacump pump. The filtered sample was dried, followed by the FTIR test. The results showed that there were microplastics in the squid and mackerel in Tambak Lorok Semarang, FTIR showed that there were plastic polymers of nitrile and nylon types. 


2021 ◽  
Vol 5 (1) ◽  
pp. 50
Author(s):  
Medya Ayunda Fitri ◽  
Farikha Alfi Syahriyah ◽  
Yulia Tri Rahkadima

Penggunaan silika sering digunakan dalam berbagai industri. Tujuan penelitian ini adalah untuk mengetahui kadar silika pada tanah vertisol di desa Bringinbendo. Penelitian ini dimulai dengan perendaman tanah pada aquadest, kemudian dicuci sebanyak 3 kali dan dikeringkan pada 110°C selama 24 jam. Selanjutnya dihaluskan hingga ukuran 250 mesh. Tahapan kedua yaitu sintesis silika dengan metode ekstraksi alkali dan diikuti presipitasi asam. 20 gram serbuk tanah diekstraksi dalam 100 ml NaOH (3, 5, dan 7M) sambil diaduk dan dipanaskan pada 80°C. Selanjutnya ditambahkan aquadest sebanyak 250 ml dan disaring menggunakan kertas Whatman. Filtrat dititrasi dengan HCl 5M sambil diaduk hingga pH mencapai 7. Suspensi dipertahankan pada temperatur kamar selama 24 jam, disaring, dan dicuci sebanyak 5 kali dengan aquadest kemudian dikeringkan. Hasil dari penelitian yaitu massa silika paling besar terdapat pada konsentrasi NaOH 7M pada waktu 1 jam yaitu 2,59 gram dan tanah vertisol di Desa Bringinbendo memiliki kadar silika dalam kategori sedang dengan persentase sebesar 77,7%.Silica is widely used in industry. The aim of this study was to determine the silica content in vertisol soil in Bringinbendo village. This research was started by soaking the soil in aquadest, then washed 3 times and dried it at 110 ° C for 24 hours. Furthermore, smoothed to 250 mesh size. The second stage is the synthesis of silica using the alkaline extraction method and the treatment of acids. 20 grams of soil powder were extracted in 100 ml NaOH (3, 5, dan 7M) while stirring and heated at 80 ° C. Next, 250 ml of aquadest was added and filtered using Whatman paper. The filtrate was titrated with 5M HCl while stirring until the pH reached 7. The suspension was maintained at room temperature for 24 hours, filtered, and 5 times with aquadest then dried. The results of the mass study were that the greatest silica was found in 7M NaOH concentration at 1 hour, namely 2.59 grams and vertisol soil in Bringinbendo Village had silica content in the medium category with a proportion of 77.7%.


Author(s):  
Adela Gómez-Luque ◽  
Juan Carlos Parejo ◽  
Maria Zoraida Clavijo-Chamorro ◽  
Fidel López-Espuela ◽  
Faustin Munyaruguru ◽  
...  

Malaria has been for millennia one of the best known and most destructive diseases affecting humans. Its high impact has aroused great interest for the development of new effective and reliable diagnostic techniques. Recently it has been recently published that hairs from mammal hosts are able to capture, hold and finally remove foreign DNA sequences of Leishmania parasites. The aim of this study was to check if Plasmodium falciparum (P. falciparum) DNA remains stable in blood samples deposited in Whatman paper after suffering different transport and storage conditions, and to compare the sensitivity of these results with those offered by thick a smear and Rapid Diagnostic Test, and besides to examine whether P. falciparum DNA would be detected and quantified by Real time quantitative PCR (qPCR) from hairs of people with different types of malaria. P. falciparum Histidine Repeat Protein II (pHRP-II) antigen detection and P. falciparum DNA were detected in 18 of 19 dry blood samples adhered to Whatman paper (94.74%), besides, Plasmodium DNA was also detected in seven out of 19 hair samples analyzed (36.84%), remaining stable until analysis for several months under the exposure to different environmental conditions. Although the sensitivity of PCR for the diagnosis of malaria in hair samples is not as high as blood analysis, the study of Plasmodium DNA presence in blood and hair could constitute a complementary tool with numerous advantages in sample collection, transport and storage. We suggest that the method could be also applied to medical, forensic and paleo-parasitological diagnosis, not only for malaria but also for searching many other pathogens in hair samples.


Molecules ◽  
2020 ◽  
Vol 25 (14) ◽  
pp. 3182
Author(s):  
Leopold Tie ◽  
Mina Răileanu ◽  
Mihaela Bacalum ◽  
Irina Codita ◽  
Ștefania Mădălina Negrea ◽  
...  

Nowadays, thanks to nanotechnological progress, which itself guides us more and more closely toward not only the efficient design of innovative nanomaterials or nanostructures, but to the improvement of their functionality, we benefit from an important asset in the battle against pathogenic illnesses. Herein, we report a versatile biocompatible plasmonic nanoplatform based on a Whatman paper incorporating positively-charged gold nanospherical particles via the immersion approach. The morphological characterization of the as-engineered-plasmonic paper was examined by SEM (scanning electron microscopy) and HRTEM (high-resolution transmission electron microscopy) investigations, while its surface chemical modification with a synthetic polypeptide, specifically RRWHRWWRR-NH2 (P2), was proved by monitoring the plasmonic response of loaded gold nanospheres and the emission signal of P2 via fluorescence spectroscopy. The as-functionalized plasmonic paper is non-cytotoxic towards BJ fibroblast human cells at bactericidal concentrations. Finally, the antimicrobial activity of the P2-functionalized plasmonic paper on both planktonic bacteria and biofilms was tested against two reference strains: Gram-positive Bacteria, i.e., Staphylococcus aureus and the Gram-negative Bacteria, i.e., Escherichia coli, determining microbial inhibition of up to 100% for planktonic bacteria. In line with the above presented nanoplatform’s proper design, followed by their functionalization with active antimicrobial peptides, new roads can be open for determining antibiotic-free treatments against different relevant pathogens.


Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1025
Author(s):  
Laurentiu Susu ◽  
Andreea Campu ◽  
Simion Astilean ◽  
Monica Focsan

Designing innovative (nano)detection platforms, respecting their low-cost and fabrication simplicity, capable to chemically detect multiple target analytes by employing the same engineered device, is still a great challenge in the multiplexed biosensor development. In this scientific context, in the current manuscript, we exploit the low-cost plasmonic calligraphy as a versatile approach to directly draw continuous plasmonic lines on Whatman paper using a regular ballpoint pen successively filled with two different anisotropic nanoparticles shapes (gold bipyramids—AuBPs and gold nanorods—AuNRs) as colloidal inks. After the efficient immobilization of the positively-charged AuBPs and AuNRs onto the paper fibres, proved by Scanning Electron Microscopy (SEM) investigations, the specificity of our as-calligraphed-paper platform is ensured by coating the selected lines with a thin layer of anionic poly(styrene sulfonate) polyelectrolyte, creating, consequently, a well-defined plasmonic array of charge-selective regions. Finally, the functionality of the well-isolated and as-miniaturized active plasmonic array is, subsequently, tested using the anionic Rose-Bengal and cationic Rhodamine 6G target analytes and proved by complementary dual optical “ON/OFF Switch” sensing (i.e. Surface-enhanced Raman Scattering sensing/metal-enhanced fluorescence sensing) onto the same plasmonic line, developing thus a simple multiplexed plasmonic array platform, which could further facilitate the well-desired biomarker detection in complex mixtures.


2020 ◽  
Vol 50 (5) ◽  
pp. 559-567
Author(s):  
Muthaiyan Lakshmanakumar ◽  
Swaminathan Sethuraman ◽  
K. S. Rajan ◽  
Uma Maheswari Krishnan ◽  
John Bosco Balaguru Rayappan

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