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Fulltext High activity of Ag-doped Cd0.1Zn0.9S photocatalyst prepared by the hydrothermal method for hydrogen production under visible-light irradiation

Yuliati L, Kimi M, Shamsuddin M

Beilstein J Nanotechnol, 2014;5:587-95.
PMID: 24991495 DOI: 10.3762/bjnano.5.69

The hydrothermal method was used as a new approach to prepare a series of Ag-doped Cd0.1Zn0.9S photocatalysts. The effect of Ag doping on the properties and photocatalytic activity of Cd0.1Zn0.9S was studied for the hydrogen production from water reduction under visible light irradiation.
A urea precursor to synthesize carbon nitride with mesoporosity for enhanced activity in the photocatalytic removal of phenol

Lee SC, Lintang HO, Yuliati L

Chem Asian J, 2012 Sep;7(9):2139-44.
PMID: 22733646 DOI: 10.1002/asia.201200383

A urea precursor was used for the first time to prepare mesoporous carbon nitride (MCN) by a thermal polymerization process with silica nanospheres as a hard template. Although the prepared MCN samples have similar structures and optical properties, it was revealed that the specific surface area, pore-size distribution, and morphology of the MCN samples depend on the initial mass ratio of urea to silica. Compared to the bulk carbon nitride (BCN) that only gave 20% phenol removal (6 h of irradiation), the activities can be enhanced up to 74% on MCN samples for photocatalytic removal of phenol under visible-light irradiation. The highest conversion was obtained on MCN with an initial mass ratio of urea to silica of 5, which has high surface area of 191 m(2) g(-1) and a nanoporous structure with uniform pore-size distribution of 7 nm. In addition to the high activity, the MCN sample also showed high photocatalytic stability.
Fulltext Highly ordered mesoporous silica film nanocomposites containing gold nanoparticles for the catalytic reduction of 4-nitrophenol

Jalani MA, Yuliati L, Lee SL, Lintang HO

Beilstein J Nanotechnol, 2019;10:1368-1379.
PMID: 31355105 DOI: 10.3762/bjnano.10.135

We report that transparent mesostructured silica/gold nanocomposite materials with an interpore distance of 4.1 nm, as-synthesized from a templated sol-gel synthesis method using discotic trinuclear gold(I) pyrazolate complex, were successfully utilized for the fabrication of thin film mesoporous silica nanocomposites containing gold nanoparticles. The material exhibited a highly ordered hexagonal structure when subjected to a thermal hydrogen reduction treatment at 210 °C. In contrast, when the material was subjected to calcination as a heat treatment from 190 to 450 °C, the thin film nanocomposites showed an intense d100 X-ray diffraction peak. Moreover, gold nanoparticles inside the thin film nanocomposites were confirmed by the presence of the d111 diffraction peak at 2θ = 38.2°, a surface plasmon resonance peak between 500-580 nm, and the spherical shape observed in the transmission electron microscope images, as well as the visual change in color from pink to purple. Interestingly, by simply dipping the material into a reaction solution of 4-nitrophenol at room temperature, the highly ordered structure of the as-fabricated silica/gold nanoparticle thin film composite after thermal hydrogen reduction at 210 °C resulted in an improved catalytic activity for the reduction of 4-nitrophenol to 4-aminophenol compared to the material calcined at 250 °C. Such catalytic activity is due to the presence of gold nanoparticles of smaller size in the silicate channels of the highly ordered mesoporous film nanocomposites.
Mesoporous carbon nitride for adsorption and fluorescence sensor of N-nitrosopyrrolidine

Sam MS, Lintang HO, Sanagi MM, Lee SL, Yuliati L

Spectrochim Acta A Mol Biomol Spectrosc, 2014 Apr 24;124:357-64.
PMID: 24503155 DOI: 10.1016/j.saa.2013.12.113

A metal-free mesoporous carbon nitride (MCN) was investigated for the first time as an adsorbent for N-nitrosopyrrolidine (NPYR), which is one of the nitrosamine pollutants. Under the same condition, the adsorption capability of the MCN was found to be higher than that of the MCM-41. Since the adsorption isotherm was consistent with Langmuir and Freundlich model equations, it was suggested that the adsorption of NPYR molecules on the MCN occurred in the form of mono-molecular layer on the heterogeneous surface sites. It was proposed that MCN with suitable adsorption sites was beneficial for the adsorption of NPYR. The evidence on the interaction between the NPYR molecules and the MCN was supported by fluorescence spectroscopy. Two excitation wavelengths owing to the terminal N-C and N=C groups were used to monitor the interactions between the emission sites of the MCN and the NPYR molecules. It was confirmed that the intensity of the emission sites was quenched almost linearly with the concentration of NPYR. This result obviously suggested that the MCN would be applicable as a fluorescence sensor for detection of the NPYR molecules. From the Stern-Volmer plot, the quenching rate constant of terminal N-C groups was determined to be ca. two times higher than that of the N=C groups on MCN, suggesting that the terminal N-C groups on MCN would be the favoured sites interacted with the NPYR. Since initial concentration can be easily recovered, the interactions of NPYR on MCN were weak and might only involve electrostatic interactions.
Liquid-gas boundary catalysis by using gold/polystyrene-coated hollow titania

Ran NH, Yuliati L, Lee SL, Mahlia TM, Nur H

J Colloid Interface Sci, 2013 Mar 15;394:490-7.
PMID: 23380399 DOI: 10.1016/j.jcis.2012.12.045

A microparticle material of gold/polystyrene-coated hollow titania was successfully synthesized. The synthesis steps involved hydrothermal synthesis of a carbon sphere from sucrose as a template, coating of the carbon sphere with titania, removal of the carbon sphere to produce hollow titania, followed by coating of polystyrene on the surface of hollow titania and then attachment of gold nanoparticles. It has been demonstrated that this material can float on water due to its low density and it is a potential catalyst for liquid-gas boundary catalysis in oxidation of benzyl alcohol by using molecular oxygen.
Fulltext Ellagic acid and hydroxyapatite promote angiogenesis marker in bone defect

Nirwana I, Munadziroh E, Yuliati A, Fadhila AI, Nurliana, Wardhana AS, et al.

J Oral Biol Craniofac Res, 2022;12(1):116-120.
PMID: 34840942 DOI: 10.1016/j.jobcr.2021.11.008

The combination of hydroxyapatite and the herbal extract ellagic acid is expected to accelerate the bone healing process (osteogenesis) due to the extract's anti-inflammatory and antioxidant properties. The osteogenesis process is closely associated with angiogenesis markers, such as fibroblast growth factor 2 (FGF-2), vascular endothelial growth factor (VEGF) and alkali phosphatase (ALP). The objective of this study is to analyse the combination of ellagic acid and hydroxyapatite to promote FGF-2, VEGF and ALP expression as angiogenesis markers in a bone defect model. The research sample comprised 30 male Wistar rats with a defect introduced on the left femur; these were divided into three groups for treatment with ellagic acid and hydroxyapatite, hydroxyapatite and polyethylene glycol (PEG) (control). On days 7 and 14 days after treatment, the Wistar rats were euthanised, and the femoral bone tissue was removed for the immunohistochemical analysis of FGF-2, VEGF and ALP expression. FGF-2 and ALP expression increased in the group treated with ellagic acid and hydroxyapatite on days 7 and 14 post treatment (p
Anti-Inflammatory Effects of Calcium Hydroxide Combined with Ellagic Acid as Pulp Capping Material: In Vivo Study

Sari AF, Nirwana I, Yuliati A, Meizarini A, Rahayu RP, Palupi R, et al.

Eur J Dent, 2024 Nov 07.
PMID: 39510525 DOI: 10.1055/s-0044-1791243

OBJECTIVES: Pulp capping is a pivotal treatment in dentistry aimed at preserving pulp vitality. While calcium hydroxide has long been considered the gold standard in pulp capping materials, its long-term use can induce chronic inflammation, ultimately leading to pulp necrosis and affecting human health. In this context, ellagic acid, a natural compound with potent anti-inflammatory properties, emerged as a promising adjunct to mitigate inflammation associated with calcium hydroxide application, thereby sustaining pulp vitality. This study aimed to investigate the inflammatory response by alterations in neutrophil, macrophage, lymphocyte, and tumor necrosis factor-α (TNF-α) expression following the treatment with a combination of calcium hydroxide and ellagic acid.
MATERIALS AND METHODS: Dental pulp perforation was made on 27 male Wistar rats on the upper first molar and then pulp capped with calcium hydroxide and ellagic acid. The pulp of the control positive group was capped with calcium hydroxide, and the control group was not capped. The teeth were then extracted after 1, 3, and 7 days posttreatment. The differences in the number of neutrophils, macrophages, lymphocytes, and TNF-α expression were analyzed using one-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) test.
RESULTS: The treatment combination of calcium hydroxide and ellagic acid showed the lowest neutrophil number and TNF-α expression compared with the other groups (p
Fulltext The efficacy of okra fruit extract on the expression of transforming growth factor beta 1 in the tooth socket of diabetic Wistar rats

Luthfi M, Yuliati, Wijayanti EH, Abdul Razak FB, Irmalia WR

Dent Res J (Isfahan), 2021;18:91.
PMID: 35003556 DOI: 10.4103/1735-3327.330872

Background: Patients with diabetes mellitus suffer from an additional macrophage dysfunction in the secretion of growth factor, which later decreases transforming growth factor beta 1 (TGF-β1). This condition disrupts proliferation and angiogenesis. Extract of okra fruit (Abelmoschus esculentus) contains flavonoid, an active substance which acts as antioxidant, anti-inflammation, and antidiabetes. The purpose of this study is to analyze the difference in TGF-β1 expression in wound-healing process after tooth extraction of diabetic Wistar rats.
Materials and Methods: This is a laboratory experimental study using pretest and posttest on 24 Wistar rats which are divided into two groups: control group (treated with streptozotocin induction but without administration of okra fruit extract) and treatment group (treated with streptozotocin induction and oral administration of 250 mg/kg okra fruit extract once a day). Extractions of the rats' mandibular left incisors were performed using a pair of modified forceps and an elevator. The tooth sockets were then irrigated using saline solution. Four rats in each group were sacrificed on day 3 (KO1, PO1), 5 (KO2, PO2), and 7 (KO3, PO3). The socket tissues from the rats were then immunohistochemically analyzed. Data were analyzed at level significance of 0.05.
Results: The average level of TGF-β1 expression in the treatment groups was higher compared to the control group: PO1 (11.59 ± 0.58), PO2 (15.15 ± 1.07), and PO3 (18.75 ± 2.73) as compared to KO1 (5.32 ± 1.69), KO2 (8.47 ± 0.60), and KO3 (9.28 ± 1.16) with P = 0.001.
Conclusion: The administration of okra fruit extract can increase the level of TGF-β1 in wounds after tooth extraction of diabetic Wistar rats.