scholarly journals FORMULATION AND CARACTERIZATION OF QUERCETIN NIOSOME WITH CONCENTRATION VARIATIONS OF SPAN 20 SURFACTANT

2021 ◽  
Vol 18 (2) ◽  
pp. 84-94
Author(s):  
Weka Sidha Bhagawan ◽  
Rahmi Annisa ◽  
Atiza Fajrin Maulidya
Keyword(s):  
Encapsulation Efficiency ◽  
Ph Value ◽  
Particle Morphology ◽  
Cholesterol Concentration ◽  
Organoleptic Properties ◽  
Reverse Phase ◽  
Yellow Colour ◽  
Measurement Results ◽  
Ph Range ◽  
Low Solubility

Quercetin has low solubility, absorption and bioavailability which limits its practical use as a drug or supplement. Therefore, it is important to formulate a quercetin niosome system with various concentrations of span 20 as a surfactant. This investigation aimed to formulate and analyse a quercetin niosome preparation with span 20 variations to provide optimal quercetin solubility. Niosomes were prepared using various concentrations of span 20. In the present study, the quercetin niosome used the reverse phase evaporation (RPE) method. Quercetin niosome is characterised by its organoleptic properties, pH value, particle morphology comprising the particle shape and size, and encapsulation efficiency. Organoleptic observations of the quercetin niosome included a yellow colour, distinctive quercetin odour and thick consistency for all formulas. The pH remained within the physiological pH range of skin. Quercetin niosome morphology was close to spherical while the niosome particle size results were 2.13 µm (F1), 2.99 µm (F2) and 3.31 µm (F3). The quercetin niosome encapsulation efficiency results were 81.86 ± 0.47% (F1), 84.02 ± 0.26% (F2) and 88.24 ± 0.10% (F3). Quercetin niosome were successfully prepared using multiple span 20 concentrations below the cholesterol concentration characterised by the measurement results of organoleptic, pH, particle morphology and encapsulation efficiency.

scholarly journals Evaluation of the Physical Stability of Nanostructured Lipid Carrier (NLC) Meloxicam Before and After Strorage 40 Days

2018 ◽  
Vol 8 (2) ◽  
Author(s):  
Rahmi Annisa ◽  
Dewi Melani ◽  
Esti Hendradi
Keyword(s):  
Particle Size ◽  
Ph Value ◽  
Physical Stability ◽  
Particle Morphology ◽  
Entrapment Efficiency ◽  
Nanostructured Lipid Carrier ◽  
Measurement Results ◽  
Before And After ◽  
Value Range ◽  
Efficiency Test

Objective: The aims this study was to determine the effect of lipid ratio Monostearin and Miglyol 808 roomates gives the physical stability after storage 40 days. Methods: The NLC making was done by using emulsification method in the formation of NLC meloxicam, 3 different lipid ratios were used, including ratios of 6: 4, 7: 3, 8: 2. Results: NLC meloxicam physical stability of the pH, viscosity, particle size, particle morphology and entrapment efficiency. NLC meloxicam belongs to semisolid preparations with pH value range of 5.72-5.87. Increasing viscosity of NLC system is caused by the increase of solid lipid. The measurement results of particle size of three different lipid formulas indicated that the lipid particle size was less than 1000 nm. Entrapment efficiency test of all NLC-lipid compositions revealed quite high result (> 80%). Conclusion: The system uses lipid monostearin NLC meloxicam and Miglyol 808 at a ratio of 8: 2 is the most optimal combination shows physical stability after storage 40 days.

scholarly journals PENGARUH SUBSTITUSI SARI KACANG KOMAK (LABLAB PURPUREUS (L.) SWEET) DAN SUSU SKIM TERHADAP SIFAT ORGANOLEPTIK, NILAI PH, DAN TOTAL BAKTERI ASAM LAKTAT YOGHURT KACANG KOMAK

2018 ◽  
Vol 12 (1) ◽  
pp. 72
Author(s):  
Astrid Widiastuti ◽  
Judiono Judiono
Keyword(s):  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Ph Value ◽  
Skim Milk ◽  
Lactobacillus Bulgaricus ◽  
Lablab Purpureus ◽  
Organoleptic Properties ◽  
Gram Staining ◽  
Randomized Design ◽  
Measurement Results

Lablab bean has potential as alternative food subtituteof soybean Lablab Bean has nutrients content which is not much  different, but fatcontent is much lower than soybean. Yogurt is milk fermented by the lactic acid bacteria Streptococcus thermophilusand Lactobacillus bulgaricusthat tranformmilk sugar (lactose) into lactic acid to obtain acidity, smell,  and specifi c fl avor. The aim of this research was to study the effect of substitution of lablab bean milk and skim milk to organoleptic properties, pH value, and the total of lactic acid bacteria (LAB). The Experimental design was appliedusing completely randomized design with 30 untrained panelists. The research conducted in three treatments with two repetitions. The data collected are total LAB and pH value. The organoleptic properties test used was hedonic quality test with one repitition. The pH value was measured using an electronic pH meter. The total of LAB was measuredusing Man Rogosa and Sharpe (MRS) media. The level of lactic acid was measured using acidity test. The treatment applied was the effect of substitution of lablab bean milk 92%, 95%, and 96,5%, and skim milk 8%, 5%, and 3,5%. Data were analyzed with Anova, Kruskal Wallis, Duncan Multi Range with signifi cance level p < 0,05. The result showedthat organoleptic properties ofsubstituion 92:8 is closer to the expected quality ofyoghurt with the lowest pH value, and the highest pH value is substitution96,5 :3,5. The measurement results of the total LAB and lactic acid levels showed the substitution 92:8 has the highest value and the substitution of 96,5:3,5 has the lowest value. The result of Microscopic on Gram staining showed that Streptococcus thermopillus and Lactobacillus bulgaricus bacteria were found in lablab beans yoghurt. This result indicates that the lablab bean can be potentially used as the main material to make yoghurt.

Improving Topical Skin Delivery of Monocrotaline Via Liposome Gel-based Nanosystems

2019 ◽  
Vol 16 (10) ◽  
pp. 940-950 ◽  
Author(s):  
Jiandong Yu ◽  
Zhi Chen ◽  
Yan-zhi Yin ◽  
Chaoyuan Tang ◽  
Enying Hu ◽  
...  
Keyword(s):  
Gradient Method ◽  
Encapsulation Efficiency ◽  
Ph Value ◽  
Topical Administration ◽  
Ph Gradient ◽  
Stability Factor ◽  
Buffer Solution ◽  
Skin Delivery ◽  
Skin Retention

Background: In this study, a liposomal gel based on a pH-gradient method was used to increase the skin-layer retention of monocrotaline (MCT) for topical administration. Methods: Using the Box-Behnken design, different formulations were designed to form liposome suspensions with optimal encapsulation efficiency (EE%) and stability factor (KE). In order to keep MCT in liposomes and accumulate in skin slowly and selectively, MCT liposome suspensions were engineered into gels. Results: A pH-gradient method was used to prepare liposome suspensions. The optimal formulation of liposome suspensions (encapsulation efficiency: 83.10 ± 0.21%) was as follows: MCT 12 mg, soybean phosphatidyl choline (sbPC) 200 mg, cholesterol (CH) 41 mg, vitamin E (VE) 5 mg, and citric acid buffer solution (CBS) 4.0 10 mL (pH 7.0). The final formulation of liposomal gels consisted of 32 mL liposome suspensions, 4.76 mL deionized water, 0.40 g Carbopol-940, 1.6 g glycerol, 0.04 g methylparaben, and a suitable amount of triethanolamine for pH value adjustment. The results of in vitro drug release showed that MCT in liposomal gels could be released in 12 h constantly in physiological saline as a Ritger-Peppas model. Compared with plain MCT in gel form, liposomal MCT in gel had higher skin retention in vitro. Conclusion: In this study, liposomal gels were formed for greater skin retention of MCT. It is potentially beneficial for reducing toxicities of MCT by topical administration with liposomal gel.

Formulation and Stability Test of Lip Cream Preparation of Kenop Flower Ethanol Extract (Gomphrena globosa L.)

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Mevi Irianti Tonapa ◽  
Rani Dewi Pratiwi ◽  
Elsye Gunawan
Keyword(s):  
Ph Value ◽  
Ethanol Extract ◽  
Stability Test ◽  
Gomphrena Globosa ◽  
Homogeneous Composition ◽  
Semi Solid ◽  
The Stability ◽  
Ph Range ◽  
Average Dispersion ◽  
Brown Color

Kenop Flower (Gomphrena globosa L.) is used in the manufacture of lip cream because contains betacyanin pigments that function as color pigments. This study aims to determine the physical quality and stability of the lip cream preparation of the ethanol extract of kenop flower (Gomphrena globosa L.). This research was conducted experimentally, including the manufacture of lip cream formulations with ethanol extract of kenop flower (Gomphrena globosa L.) with a concentration of 10%. The results of the physical examination test for lip cream preparations for all preparations have a distinctive vanilla aroma with a semi-solid texture, F0 has ivory white color and F1-F3 has a brown color. The preparations had a homogeneous composition, average pH 6-7, had good greasing power, 5.0-5.8 average dispersion and 60.33-66.67 seconds average adhesion. The stability test carried out on day 28 found that all preparations were stable, had a distinctive vanilla aroma with a semi-solid texture, F0 had ivory white color and F1-F3 had a brown color. The preparation has a homogeneous composition; the average pH is 6-7. Where the lip cream formulas F1 and F3 decreased the pH value on the 28th day from 7 to 6 but tended to be stable and in the pH range that matched the lip pH. And there is no phase separation in all formulas.

SIGNIFICANT EFFECT OF PH ON PHOTOCATALYTIC DEGRADATION OF ORGANIC POLLUTANTS USING SEMICONDUCTOR CATALYSTS

2016 ◽  
Vol 78 (8-3) ◽  
Author(s):  
Nur Farhana Jaafar ◽  
Aishah Abdul Jalil ◽  
Sugeng Triwahyono ◽  
Adnan Ripin ◽  
Mohamad Wijayanuddin Ali
Keyword(s):  
Carbon Dioxide ◽  
Methyl Orange ◽  
Physicochemical Properties ◽  
Photocatalytic Degradation ◽  
Organic Pollutants ◽  
Ph Value ◽  
Effect Of Ph ◽  
Electrolysis Method ◽  
Ph Range ◽  
Positively Charged

Photocatalytic is one of the inexpensive and non-toxic techniques for degradation of organic pollutants into harmless substances such as water and carbon dioxide. In this study, simple electrolysis method was used in preparation of Ag/TiO2 and α-Fe2O3/HY catalysts. The physicochemical properties of the catalysts were studied using XRD, FTIR, FESEM-EDX and surface area analysis. The pH of solution plays an important role in the photocatalytic degradation of organic pollutants which influences the surface-charge properties of the catalysts. Ag/TiO2 and α-Fe2O3/HY were used as catalyst on degradation of 2-chlorophenol (2-CP) and methyl orange (MO), respectively. The effect of pH on degradation of 2-CP and MO were investigated over a pH range from 2 to 9. Higher degradation of 2-CP and MO were obtained at pH 5 (74%) and pH 2 (80%), respectively. This finding might be explained by the amphoteric performance of the catalyst using point zero charge (pHZPC). The pHZPC for Ag/TiO2 and α-Fe2O3/HY was found to be at pH 6.3 and pH 7.2, respectively. Hence, the activities of the catalysts may have been affected by the existence of a strong electrostatic field between the positively charged catalysts surface and negatively charged 2-CP and MO caused a pH value lower than their pHZPC give greater degradation.

scholarly journals TiO2 Nano Flowers Based EGFET Sensor for pH Sensing

Coatings ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 251
Author(s):  
Chih-Chiang Yang ◽  
Kuan-Yu Chen ◽  
Yan-Kuin Su
Keyword(s):  
Ph Value ◽  
Ph Sensor ◽  
High Sensitivity ◽  
Experimental Result ◽  
Ph Sensing ◽  
Voltage Reference ◽  
Ph Sensors ◽  
Oxide Substrate ◽  
Ph Range ◽  
The Relationship

In this study, pH sensors were successfully fabricated on a fluorine-doped tin oxide substrate and grown via hydrothermal methods for 8 h for pH sensing characteristics. The morphology was obtained by high-resolution scanning electron microscopy and showed randomly oriented flower-like nanostructures. The TiO2 nanoflower pH sensors were measured over a pH range of 2–12. Results showed a high sensitivity of the TiO2 nano-flowers pH sensor, 2.7 (μA)1/2/pH, and a linear relationship between IDS and pH (regression of 0.9991). The relationship between voltage reference and pH displayed a sensitivity of a 46 mV/pH and a linear regression of 0.9989. The experimental result indicated that a flower-like TiO2 nanostructure extended gate field effect transistor (EGFET) pH sensor effectively detected the pH value.

Why is the hydrolytic activity of acetylcholinesterase pH dependent? Kinetic study of acetylcholine and acetylthiocholine hydrolysis catalyzed by acetylcholinesterase from electric eel

2018 ◽  
Vol 73 (9-10) ◽  
pp. 345-351 ◽  
Author(s):  
Alena Komersová ◽  
Markéta Kovářová ◽  
Karel Komers ◽  
Václav Lochař ◽  
Alexander Čegan
Keyword(s):  
Catalytic Activity ◽  
Ionic Strength ◽  
Ph Value ◽  
Hydrolytic Activity ◽  
Initial Substrate ◽  
Electric Eel ◽  
Value Range ◽  
Ph Dependent ◽  
Ph Range ◽  
Initial Substrate Concentration

AbstractThe dependence of the activity of acetylcholinesterase from electric eel at a pH value range of 4.8–9.8 (phosphate buffer), regarding acetylcholine and acetylthiocholine hydrolysis, was determined at 25 °C, ionic strength of 0.11 M, and initial substrate concentration of 4 mM. At a pH range of 4.8–9.8, the dependencesA(pH) form a sigmoid increasing curve with the maximum catalytic activity at a pH range 8–9.5. For acetylcholine hydrolysis, the kinetic reason for such an increase inAconsists mainly of an increase in the rate constantk2(Michaelis-Menten) model with increasing pH of the reaction mixture. For acetylthiocholine hydrolysis, the kinetic explication of the determined dependenceA(pH) is more complicated.

scholarly journals Structure of bovine cytochromecoxidase in the ligand-free reduced state at neutral pH

2018 ◽  
Vol 74 (2) ◽  
pp. 92-98 ◽  
Author(s):  
Fangjia Luo ◽  
Kyoko Shinzawa-Itoh ◽  
Kaede Hagimoto ◽  
Atsuhiro Shimada ◽  
Satoru Shimada ◽  
...  
Keyword(s):  
Ph Value ◽  
Proton Pumping ◽  
Molecular Surface ◽  
Cellular Respiration ◽  
Inner Mitochondrial Membrane ◽  
Ph Change ◽  
Structural Alterations ◽  
Ligand Free ◽  
Wide Ph Range ◽  
Ph Range

Cytochromecoxidase (CcO), the terminal oxidase in cellular respiration, couples proton pumping to O2reduction. Mammalian CcO resides in the inner mitochondrial membrane. Previously, a model of H-pathway proton pumping was proposed based on various CcO crystal structures. However, all previously determined structures were solved using crystals obtained at pH 5.7, which differs from the environmental pH of CcO in the inner membrane. The structures of fully oxidized and ligand-free reduced CcO at pH 7.3 have now been determined. Structural comparison between the oxidized and reduced states revealed that the structural alterations that occurred upon redox change at pH 5.7 in Asp51, the magnesium-containing cluster, haem groups and helix X, which provide important structural evidence for the H-pathway proton-pumping proposal, also occur at pH 7.3. These structural alterations were restricted to a local region of CcO; no domain movement was detected, nor were significant structural alterations detected in peripheral regions at either pH value. These observations indicate that the small and precise structural alterations that occur over the course of the reaction cycle are not affected by pH change, and that isolated CcO precisely performs proton pumpingviathe H-pathway over a wide pH range. Because the pH is not uniform across the molecular surface of CcO, the fact that the overall structure of CcO is not affected by pH changes ensures the high enzymatic efficiency of this protein in the mitochondria.

Influence of pH on the Absorption and Fluorescence Spectra of 6,7-Dihydroxycoumarin in Aqueous Solution

1982 ◽  
Vol 37 (3) ◽  
pp. 262-265 ◽  
Author(s):  
Jerzy Grzywacz ◽  
Stanisława Taszner
Keyword(s):  
Aqueous Solution ◽  
Fluorescence Spectra ◽  
Singlet State ◽  
Ph Value ◽  
Emission Spectra ◽  
Excited Singlet ◽  
Acid Base ◽  
Wide Ph Range ◽  
Ph Range ◽  
Influence Of Ph

Abstract Absorption and emission spectra of 6,7-dihydroxycoumarin [6,7-DHC] in aqueous solution over a wide pH range are reported. The absorption spectra proved to be strongly sensitive to the pH-value of the solution, whereas the emission spectra change in this range only insignificantly. An interpretation is attempted on the basis of the differences of the acid-base properties of the 6,7-DHC molecule in its ground and excited singlet state. For this purpose the pKa's and pKax's values have been calculated. It has been stated that in the excited state the phototautomer form is very unlikely.

scholarly journals Fabrication of Eco-Friendly Superabsorbent Composites Based on Waste Semicoke

Polymers ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2347
Author(s):  
Yongsheng Wang ◽  
Yongfeng Zhu ◽  
Yan Liu ◽  
Aiqin Wang
Keyword(s):  
Acrylic Acid ◽  
Ph Value ◽  
High Water ◽  
Sem Analysis ◽  
Water Absorbency ◽  
Ammonium Persulphate ◽  
Wide Ph Range ◽  
Maximum Water ◽  
Ph Range ◽  
Superabsorbent Composites

A series of novel superabsorbent composites of poly(acrylic acid)/semicoke were prepared by polymerization of acrylic acid using ammonium persulphate as initiator, N,N′-methylenebisacrylamide as crosslinker and semicoke which was the by-product of coal carbonizing as the inorganic components. FTIR and SEM analysis indicated that the superabsorbent composites had been successfully polymerized and the semicoke participated in construction of the 3D polymeric network. Meanwhile, the effects of initiator, crosslinker, semicoke, and neutralization degree, as well as the pH value, were investigated, and the results showed that superabsorbent composites containing 10% of semicoke possessed the maximum water absorbency of 584 g/g in distilled water and 75 g/g in 0.9% NaCl solution. The superabsorbent composites kept the high water absorbency within a wide pH range of 4–11, and still exhibited better re-swelling capability even after seven times. The superabsorbent composite with its excellent performance is a potential water-retaining agent used in agriculture.

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