Se Samples Research Articles

Boosting the thermoelectric properties of n-type PbSe through the dual incorporation of Sb and Al

PbSe has attracted significant attention as a medium-temperature thermoelectric (TE) material due to its abundance and low cost. This study demonstrate that in the novel thermoelectric system of AlxPb0.9975Sb0.0025Se samples (x = 0, 0.005, 0.01, 0.02, and 0.03), the electronic conductivity of pure PbSe was enhanced by Sb doping. Introducing a small amount of Al to occupy the Pb vacancies not only increases the Hall carrier concentration in PbSe, but also resulting in an increase in Seebeck coefficient (S). At 873 K, the power factor (PF) of the sample with x = 0.02 increases to 16 μW cm−1 K−2. In addition, the total thermal conductivity did not increase significantly, so the thermoelectric performance was effectively improved, a maximum figure of merit (ZT) of 1.8 is achieved at 873 K, along with a high average ZT (ZTavg) of approximately 1 over the temperature range of 300–873 K.

Microstructural Instability and Its Effects on Thermoelectric Properties of SnSe and Na-Doped SnSe.

Effects of thermal cycling on the microstructure and thermoelectric properties are studied for the undoped and Na-doped SnSe samples using X-ray computed tomography and property measurements. It is observed that thermal cycling causes significant cracks to develop, which decrease both the electrical and lattice thermal conductivities but do not affect the thermopower. The zT values are drastically reduced after the repeated heat treatment. It is important to account for density changes during cycling to obtain accurate values of the thermal conductivity. Even before thermal cycling, the spark-plasma sintered (SPS) samples have a significant number of microcracks. The orientation of cracks within the SPS pellets and their effect on the microstructure are influenced by the presence of a Na-rich impurity. The SnSe and Sn0.995Na0.005Se samples without the impurity develop cracks and exhibit grain growth parallel to the pellet surface, which is also the plane of the 2D SnSe layers. The Sn0.97Na0.03Se sample containing the impurity develops cracks that are orthogonal to the pellet surface. Such an orientation of cracks in Sn0.97Na0.03Se inhibits grain growth. All samples appear mechanically unstable after thermal cycling.

Abstract PO4-08-09: Concordance analysis of paired breast cancer core needle biopsies and surgical excision samples using the Oncotype DX Breast Recurrence Score® assay

Abstract INTRODUCTION: The Oncotype DX Breast Recurrence Score® (RS) assay is validated to predict risk of distant recurrence at 10 years and the benefit of adjuvant chemotherapy in patients with estrogen receptor (ER)+, HER2- early breast cancer who receive 5 years of endocrine therapy. The feasibility of Oncotype DX® testing with diagnostic core needle biopsies (CNB) was demonstrated through analysis of a large commercial laboratory experience. The neoadjuvant ADAPT study showed the clinical utility of deriving the Recurrence Score® (RS) result from CNB as well. However, data are limited on concordance of RS results from paired CNB and surgical samples. Our primary objective was to determine the degree of concordance of RS results between paired tissue samples from the same primary breast tumor of patients with early stage, ER+, HER2- invasive breast cancer who had a CNB and subsequent surgical excision (SE; lumpectomy or mastectomy) without intervening systemic therapy. METHODS: Patients with a commercial RS result on either CNB or subsequent SE were identified through medical record and clinical database review. A pathologist reviewed archival tissue samples to confirm eligibility and selected the other paired CNB or SE block most representative of the tumor tissue for subsequent study Oncotype DX testing. Descriptive statistics were used to summarize patient and tumor characteristics. Wilcoxon signed rank, McNemar’s and Cochran-Mantel-Haenszel tests were used to compare RS between SE and CNB paired samples. Cohen’s Kappa and 95% confidence intervals (CIs) were used to compare the agreement of categorical RS (0-25 and 26-100) result between SE and CNB paired samples. Lin’s concordance correlation and 95% CIs were used to compare agreement of continuous RS between paired samples. RESULTS: A total of 134 patients were identified with paired CNB and SE samples with a median time of 34 (range 5-103) days between collections. Of the 134 patients, a commercial RS result was available for 25 (18.7%) with CNB and 109 (81.3%) with SE. A study RS result was then generated on the other paired sample. Median age was 62 years (range 33-99; 23 patients [17%] were age ≤50 vs. 111 [83%] age >50). Cases were predominantly node negative (107/134 node negative vs. 26/134 node positive; 1/134 unknown) invasive ductal carcinomas (104/134 ductal vs. 18/134 classic lobular vs. 12/134 other). Mean RS results were 15.6 (range 0-56) and 16.6 (range 0-59) for CNB and SE, respectively (p = 0.003), with no statistically significant differences in RS category defined as low vs. high risk (119/134 CNB vs. 114/134 SE for RS 0-25 and 15/134 CNB vs 20/134 SE for RS 26-100; p = 0.13) or low vs. intermediate vs. high risk (85/134 CNB vs. 78/134 SE for RS 0-17 and 43/134 CNB vs. 48/134 SE for RS 18-30 and 6/134 CNB vs. 8/134 SE for RS 31-100; p = 0.19). No differences were observed based on age relative to 50 years or nodal status (data not shown). Cohen’s Kappa statistic k = 0.64 (95% CI, 0.44-0.83) supports substantial agreement between the CNB and SE samples. Lin’s concordance correlation coefficient (CCC) demonstrates similar agreement for the continuous RS result between paired samples (CCC = 0.86 [0.80-0.90]). Overall percent agreement was 91.8% (87.1-96.4%). CONCLUSIONS: Studies evaluating the level of concordance of ER, progesterone receptor, and HER2 biomarker status between CNB and SE samples have found high concordance rates, albeit varied. We now provide data demonstrating high concordance of RS results between CNB and SE specimens obtained from the same breast primary tumor without intervening systemic therapy. This supports use of either biopsy source for testing with a genomic predictor to identify those patients who will most likely benefit from chemotherapy and which patients may be spared. Citation Format: Aziza Nassar, Jodi Carter, Paige Innis, Satish Seerapu, Christy Russell, Helena Hanna, Abigail Lochala, Minetta Liu. Concordance analysis of paired breast cancer core needle biopsies and surgical excision samples using the Oncotype DX Breast Recurrence Score® assay [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO4-08-09.

Enhancement of thermoelectric properties in rapidly synthesised β-Cu2Se using optimized Cu content and microwave hybrid heating

To our knowledge, this is the first study to successfully synthesise high-temperature-phase copper selenide (β-Cu2Se) at room temperature using rapid microwave hybrid heating (MHH). Controlling the starting Cu/Se ratio is the critical parameter for adjusting the content of α- and β-phases in the as-synthesised sample. The relatively low Cu composition causes impurities to form in the Cu3Se2 phase, deteriorating the thermoelectric (TE) properties of the Cu2Se material. The β phase formation at room temperature promotes electrical conductivity. The thermal conductivities of the Cu2.0Se samples were 0.5–0.8 Wm−1K−1 at 303–673 K. A strong electronic-phonon interaction may potentially couple electronic thermal conductivity (κe) and lattice thermal conductivity (κL), resulting in incomplete separability of κL and κe in the β-Cu2.0Se sample. The Cu2.0Se exhibited a ZT value of 0.65 at 523 K because of its considerably lowered thermal conductivity.

Probing an enhanced anisotropy Seebeck coefficient and low thermal conductivity in polycrystalline Al doped SnSe nanostructure

Recently, SnSe based thermoelectric materials attained much interest due to their environment friendly IV–VI semiconductor group. Herein, Al doped SnSe (Sn1−xAlxSe) specimens were prepared by combined ball milling and spark plasma sintering. High resolution transmission electron microscopy analysis of (Sn1−xAlxSe) nanostructure samples confirmed the existence of different crystal defects and dislocation induced by Al doping. Lower thermal conductivity (0.63 W/mK at 750 K) is observed for Sno.92Al0.08Se samples than pristine SnSe (1.14 W/mK at 750 K), which is mainly attributed to various crystal defects, such as lattice dislocation, stacking fault, grain boundary scattering, and excellent anharmonic bonding nature of SnSe. The maximum electrical conductivity is observed for the SAS-2 sample, which correlates well with the low activation energy of 0.20 eV. The minimal doping of Al (SAS-2) decoupled the strong interdependency of electrical and thermal transport properties, leading to a maximum ZT of 0.18 at 743 K. The Al doped SnSe (Sn1−xAlxSe) induced point defects in the sample, which provides a new strategy for waste heat recovery.

Lignin Microspheres Modified with Magnetite Nanoparticles as a Selenate Highly Porous Adsorbent.

Highly porous lignin-based microspheres, modified by magnetite nanoparticles, were used for the first time for the removal of selenate anions, Se(VI), from spiked and real water samples. The influence of experimental conditions: selenate concentration, adsorbent dosage and contact time on the adsorption capacity was investigated in a batch experimental mode. The FTIR, XRD, SEM techniques were used to analyze the structural and morphological properties of the native and exhausted adsorbent. The maximum adsorption capacity was found to be 69.9 mg/g for Se(VI) anions at pH 6.46 from the simulated water samples. The modified natural polymer was efficient in Se(VI) removal from the real (potable) water samples, originated from six cities in the Republic of Serbia, with an overage efficacy of 20%. The regeneration capacity of 61% in one cycle of desorption (0.5 M NaOH as desorption solution) of bio-based adsorbent was gained in this investigation. The examined material demonstrated a significant affinity for Se(VI) oxyanion, but a low potential for multi-cycle material application; consequently, the loaded sorbent could be proposed to be used as a Se fertilizer.

Hydrotreatment of Supercritical Carbon Dioxide Extracts of Hydrothermal Liquefaction Lignocellulosic Biocrude

Raw lignocellulosic biocrude produced by hydrothermal liquefaction and its supercritical carbon dioxide extract (SE) were hydrotreated at 350–405 °C and for 2–6 h utilizing commercial CoMo and NiMo catalysts. The hydrotreatment reduced the oxygen content of the SE down to 1.6 wt %, while the minimum oxygen content of the hydrotreated biocrude (HBC) was 3.1 wt %. No coke formation was observed in the hydrotreatment of the SE, while the yield of coke was 13 wt % when processing the raw biocrude. The hydrotreated SE (HSE) samples exhibited molecular weights 24–61% lower than that of the HBC samples, with larger low-boiling fractions (up to diesel). The better quality of the HSE and the absence of coke, together with the lower metal content of SE (0.2 g/kg) versus BC (8.5 g/kg), suggest that the implementation of hydrotreatment on SEs, instead of raw lignocellulosic biocrude, is a promising option.

High-field conduction in fresh and aged samples of Se and As2Se3 glasses

High-field conduction in fresh and aged samples of Se and As2Se3 glasses

MiR 31-3p Has the Highest Expression in Cesarean Scar Endometriosis.

Micro-RNAs expression can vary between different forms of endometriosis, but data on miRNA expression in cesarean scar endometriosis is lacking. The present study is comprised of 30 patients with endometriosis in the cesarean scar (scar endometriosis, SE), 14 patients with deep infiltrating endometriosis (DIE), 47 patients with endometrioma (ovarian endometrial cyst, OE), and 33 patients with healthy ovarian tissue as the control group (CG). In the initial experiment to identify possible dysregulated miRNAs, the levels of 754 miRNAs in formalin-fixed paraffin-embedded tissue (FFPE) samples from OE, high-grade ovarian cancer, endometrioid ovarian cancer, and CG were measured. We identified seven potentially dysregulated miRNAs: miR-1-3p, miR-31-3p, miR-125b-1-3p, miR-200b-3p, miR-548d, miR-502, and miR-503. We then examined the expression profiles of each of these miRNAs individually in the SE, DIE, OE, and CG FFPE samples using RT-qPCR. miR-31-3p had significantly higher levels of expression and miR-125b-1-3p had significantly lower levels of expression in SE compared to the controls. Overall, the higher expression levels of miR-31-3p and the lower expression levels of miR-125b-1-3p are consistent with the benign nature of SE. Importantly, the results of the present study demonstrate the possibility of using miRNA to monitor the risk of malignant transformation of endometriosis tissue.

Purification of Hydrogen from CO with Cu/ZSM-5 Adsorbents.

The transition to a hydrogen economy requires the development of cost-effective methods for purifying hydrogen from CO. In this study, we explore the possibilities of Cu/ZSM-5 as an adsorbent for this purpose. Samples obtained by cation exchange from aqueous solution (AE) and solid-state exchange with CuCl (SE) were characterized by in situ EPR and FTIR, H2-TPR, CO-TPD, etc. The AE samples possess mainly isolated Cu2+ cations not adsorbing CO. Reduction generates Cu+ sites demonstrating different affinity to CO, with the strongest centres desorbing CO at about 350 °C. The SE samples have about twice higher Cu/Al ratios, as one H+ is exchanged with one Cu+ cation. Although some of the introduced Cu+ sites are oxidized to Cu2+ upon contact with air, they easily recover their original oxidation state after thermal treatment in vacuum or under inert gas stream. In addition, these Cu+ centres regenerate at relatively low temperatures. It is important that water does not block the CO adsorption sites because of the formation of Cu+(CO)(H2O)x complexes. Dynamic adsorption studies show that Cu/ZSM-5 selectively adsorbs CO in the presence of hydrogen. The results indicate that the SE samples are very perspective materials for purification of H2 from CO.

The content and health risk assessment of selected elements in bee pollen and propolis from Turkey

This study aimed to determine the concentrations of potentially toxic elements (PTEs), including Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, Se, Sn, V, and Zn, in pollen and propolis samples collected from migratory beekeeping areas in Turkey. A health risk assessment was performed to identify the potential risk of these PTEs to consumers in terms of public health. Concentrations of the elements were analyzed by inductively coupled plasma optical emission spectroscopy. The most abundant element in the bee pollen and propolis samples was Fe, with average concentrations of 47.3 and 390 mg kg−1, respectively, followed by Al, Zn, Mn and Sn. Concentrations of all elements except Cu, Mn and Sn were higher in propolis than in pollen. The concentrations of Fe, Al, and Zn in the propolis samples were over eight, seven, and two times higher than in the bee pollen samples, respectively. Se, Cd, and Hg in pollen and Se and Cd in propolis were below the detection limits. Pb, Co, and Cr were detected below 0.62, 0.06, and 0.91 mg kg−1, in pollen samples, respectively. Co and Hg were detected below 0.68, and 0.18 mg kg−1, in propolis samples, respectively. Detection of the PTEs contamination level and assessment of the health risks in pollen and propolis is necessary to ascertain quality and safety before consumption. In this study, we concluded that bee pollen and propolis may be good indicators for the screening of environmental pollution with PTEs and standards regulating acceptable concentrations of these pollutants in bee products should be established. In addition, it has been determined that consumption at the specified rates does not pose a risk. This study suggests the determination of admissible concentrations of PTEs in bee pollen and propolis.

The influence of selenium amount added into the graphite box during the selenization of solution deposited CIGSe thin films.

Cu(In,Ga)Se2 (CIGSe) semiconductor is an efficient light absorber material for thin-film solar cell technology. The sequential evaporation of precursor solution, followed by the selenization process, is a promising non-vacuum and low-cost approach for CIGSe thin-film fabrication. The main properties of CIGSe thin films are strongly affected by the post-selenization step. Hence, thorough control of selenization parameters is essential for achieving pure crystalline, large grain films needed for high-performance solar cell devices. In this study, the impact of selenium (Se) amount added during the selenization step was evaluated. The structural, morphological, and compositional properties of the selenized thin films were investigated. The CIGSe precursor film was deposited by a spin-coating technique using a thiol/amine-based solution, followed by annealing with different Se amounts (100, 200, and 300 mg) within a partially closed small round graphite container. In all cases, uniform films of 1.2–1.5 µm thickness with a well-defined single chalcopyrite phase were obtained. It was observed that the grain size and Se content increased with increasing Se mass added. Moreover, the sample selenized with 200 mg Se resulted in higher surface coverage, thinner fine-grained layer, and less MoSe2 formation than the excess Se samples.

Selenium-amended biochar mitigates inorganic mercury and methylmercury accumulation in rice (Oryza sativa L.)

Rice, as a dominant crop in China and Asia, can be a major route of methylmercury (MeHg) exposure for humans in inland China, especially in those living in mercury (Hg) polluted areas. Soil is the most prominent MeHg accumulation source for rice grains. The development of management practices to reduce MeHg in rice grains is crucial. This study explored the mitigation effect of biochar (BC) and sodium selenite-amended biochar (BC + Se) on MeHg production in paddy soil and accumulation in rice. Mercury-contaminated soil was treated with 1% and 5% of both BC and BC + Se. Soil MeHg concentration slightly increased under 1% BC/BC + Se compared to control soil but decreased at the rate of 5%. Moreover, soil phytoavailable MeHg (P–MeHg) diminished as the amount of Se-amended BC increased. BC + Se effectively mitigated MeHg accumulation in rice grains. The highest average contents of MeHg and inorganic Hg (IHg) in rice seeds were found in the control samples, followed by the 1%-BC, 5%-BC, 1%-BC + Se, and 5%-BC + Se samples. Under the 5%-BC + Se treatment, rice MeHg levels were reduced significantly (94%) compared to the control, and P–MeHg concentrations in soil were lower than all the other experimental groups throughout the rice-growing season. These results demonstrate the effectiveness of BC + Se in reducing MeHg and IHg accumulation in rice and could be employed for remediation of Hg polluted paddies.

Grace Catalysts Technologies reports 1Q 2021 results; delivers strong start to the year

Wide gap II-VI semiconductors are still in the center of interest as they can be applied in bandgap engineering, interband and intersubband transitions, diluted materials, and devices. It is because of the possibility of tuning material properties by alloying to get the required parameters of devices.The paper shows the application of piezoelectric photothermal spectroscopy to determine the energy gap and the thermal diffusivity of CdxZn1−xSe mixed crystals. It is shown that both of these parameters could be obtained due to the measurements and the interpretation of the piezoelectric photothermal phase spectra.The influence of the surface preparation on the character of the amplitude and phase piezoelectric photothermal spectra is investigated for Cd0.3Zn0.7Se and Cd0.5Zn0.5Se samples and presented. The proper method of surface treatment of the material is essential for the device quality, and the piezoelectric photothermal method gives the possibility to choose and evaluate the appropriate one.The character of the dependences of the energy gap values and thermal diffusivities of CdxZn1−xSe crystals on their composition is investigated and presented.

Photothermal determination of the optical and thermal parameters of CdxZn1-xSe mixed crystals

Wide gap II-VI semiconductors are still in the center of interest as they can be applied in bandgap engineering, interband and intersubband transitions, diluted materials, and devices. It is because of the possibility of tuning material properties by alloying to get the required parameters of devices.The paper shows the application of piezoelectric photothermal spectroscopy to determine the energy gap and the thermal diffusivity of CdxZn1−xSe mixed crystals. It is shown that both of these parameters could be obtained due to the measurements and the interpretation of the piezoelectric photothermal phase spectra.The influence of the surface preparation on the character of the amplitude and phase piezoelectric photothermal spectra is investigated for Cd0.3Zn0.7Se and Cd0.5Zn0.5Se samples and presented. The proper method of surface treatment of the material is essential for the device quality, and the piezoelectric photothermal method gives the possibility to choose and evaluate the appropriate one.The character of the dependences of the energy gap values and thermal diffusivities of CdxZn1−xSe crystals on their composition is investigated and presented.

Valence Band Structure of Chalcogenide Obtained by X‐Ray Photoelectron Spectroscopy and Etching Technique

Chalcogenide glass, such as GeSe, has been widely used in the selector device for high‐density vertically stackable memory application due to their nonlinear electrical property. The electronic structure of the valence band, from which the nature of the bonding, the short‐range structure, and the Fermi level can be obtained, is of great importance to understand their unique electrical behavior. However, the surface oxidation issue makes it difficult to obtain the accurate valence band structure by X‐ray photoelectron spectroscopy (XPS). Herein, XPS depth profiles using the combination of the monatomic and cluster ion etching are performed to determine the valence band structures of amorphous Ge–Se films capped with a thin carbon layer. The completely different etching behavior dependent on composition in the depth profiles may be closely associated with the intrinsic bonding configurations of the amorphous films. After obtaining the fresh surface, the intrinsic valence band structures of amorphous Ge–Se samples demonstrate the different bonding behavior and short‐range structure. Most importantly, the Fermi level of amorphous GexSe100−x compounds is also determined.

Synergistic Enhancement of Thermoelectric Performances by Cl-Doping and Pb-Excess in (Pb,Sn)Se Topological Crystal Insulator.

We investigated the thermoelectric properties of the Pb0.75Sn0.25Se and Pb0.79Sn0.25Se1−xClx (x = 0.0, 0.2, 0.3, 0.5, 1.0, 2.0 mol.%) compounds, synthesized by hot-press sintering. The electrical transport properties showed that low concentration doping of Cl (below 0.3 mol.%) in the Pb-excess (Pb,Sn)Se samples increased the carrier concentration and the Hall mobility by the increase of carriers’ mean free path. The effective mass of the carrier was also enhanced from the measurements of the Seebeck coefficient. The enhanced effective masses of the carrier by the Cl-doping can be understood by the enhanced electron-phonon interaction, caused by the crystalline mirror symmetry breaking. The significantly decreased lattice thermal conductivities showed that the crystalline mirror symmetry breaking decreased the lattice thermal conductivity of the Pb-excess (Pb,Sn)Se. By the Cl-doping and the Pb-excess’s synergistic effect, which can suppress the bipolar effect, the zT values of x = 0.2 and 0.3 mol.% reached 0.8 at 773 K. Therefore, we suggest that Pb-excess and the crystalline mirror symmetry breaking by Cl-doping are effective for high thermoelectric performance in the (Pb,Sn)Se.

Selective sulfuration, phosphorization and selenylation: A universal strategy toward Co-Ni-M@CeO2/NF (M = O, S, P and Se) interface engineering for efficient water splitting electrocatalysis

Although the Co-Ni-M (M = O, S, P and Se) materials exhibit excellent oxygen evolution or hydrogen evolution properties, they still display inferior overall water splitting activity, thus hindering their large-scale practical industrial application. Constructing a heterogeneous Co-Ni-M/oxide interface (M = O, S, P and Se) would be a promising approach to enhance the water splitting performance of Co-Ni-M (M = O, S, P and Se) samples in an alkaline medium, however, that it remains unexplored and challenged. In this paper, the Co-Ni-M@CeO2/NF (M = O, S, P and Se) electrodes was firstly in situ grown on three-dimensional (3D) conductive nickel foams (NF) support through selective sulfuration, phosphorization and selenylation of the Co-Ni-O@CeO2 under a N2 atmosphere. The Co-Ni-S@CeO2/NF display superior oxygen evolution reaction performance with requiring overpotential of 170 mV@20 mA cm−2 and Co-Ni-P@CeO2/NF display excellent hydrogen evolution reaction activity with requiring an overpotential 120 mV@10 mA cm−2 in an alkaline medium. What’s more, an electrode pairing of Co-Ni-S@CeO2/NF//Co-Ni-P@CeO2/NF was assembled for overall water splitting using the Co-Ni-S@CeO2/NF material as anodic catalyst together with the Co-Ni-P@CeO2/NF material as efficient cathodic catalyst. The assembled alkaline electrolyzer required a relatively small cell voltage of 1.60 V to obtain a current density of 10 mA cm−2, which is one of the best electrocatalytic activities reported so far. The Co-Ni-S@CeO2/NF//Co-Ni-P@CeO2/NF also displayed relatively satisfactory durability and the current density had no significant attenuation during a 10 h electrocatalytic measurement in 1.0 M KOH. This selective sulfuration, phosphorization and selenylation strategy is effective in developing the M hybrid /oxide interface (M = O, S, P and Se) for overall water splitting applications.

Accumulation of Phyto-mediated nano-CeO2 and selenium doped CeO2 on Macrotyloma uniflorum (horse gram) seed by nano-priming to enhance seedling vigor

Abstract Herein, we designed a facile nano-bio catalyst by equipping Phyto-mediated Cerium oxide (CeO2 NPs) and Selenium doped Cerium oxide (Se–CeO2 NPs) in a simplistic green way to boost germination and vigor of horse gram seeds with probable values on accumulation. High stable nano CeO2 was prepared with aqueous seed extract of Cassia angustifolia by an optimized amount of ammonium ceric sulphate solution, temperature, pH, and reaction duration. The properties and activities of CeO2 NPs were enhanced by the addition of sodium selenite as a source of selenium dopant. The powdered samples of CeO2 and Se–CeO2 were annealed and characterized using UV-DRS, FT-IR, XRD, DLS, and HRTEM with EDAX. The screened parameters define the particle size of CeO2 and Se–CeO2 which helps to protect plant cells without impairment. The Phyto-mediated CeO2 and Se–CeO2 nanoparticles were made to invigorate in Macrotyloma uniflorum (horse gram) seeds by nano-priming treatment. The determined germination rate, root phenotype, shoot phenotype, and vigor index by nano-priming were correlated with the hydropriming method without a negative impact. The cytotoxicity of the synthesized samples was also tested in the Vero cell line using MTT assay to prove its non-toxic nature. The effect of translocation and accumulation of CeO2 and Se–CeO2 was examined by viewing the cross-sectional images of root and stem in SEM with EDAX. The result investigates with conserve nanotechnological scheme on small scale application by nano-priming proves the existence of CeO2 and Se–CeO2 in the Macrotyloma uniflorum (horse gram) seed which primes the rapid yield in seed germination and seedlings vigor. The novel stable nano-bio catalyst Se–CeO2 with high protein plant source and sodium selenite as a dopant compound to enhance the yield of horse gram seed compared to CeO2 without raising cytotoxicity.

IN VITRO ANTI-WRINKLE AND TYROSINASE INHIBITORY ACTIVITIES OF GRAPEFRUIT PEEL and STRAWBERRY EXTRACTS

The research aims to analyse the antioxidant, anti-tyrosinase and anti-wrinkle activities from grapefruit (Citrus Maxima L) and strawberry extracts. Samples were extracted by maceration using 96% ethanol and ethyl acetate, subsequently. The Ferric Reducing Antioxidant Power (FRAP) and β-carotene bleaching (BCB) were used to measure the antioxidant activity. The effect of anti-wrinkle was determined by testing the inhibition of elastase and collagenase enzyme, while anti-tyrosinase activity was analysed using mushroom tyrosinase enzyme. The results showed that strawberry extracts in ethanolic (SE) and ethyl acetate (SEA) have antioxidant activity in FRAP (EC50 = 404.39 ± 3.27 µg / mL and 1978.65 ± 37.25 µg/mL) and BCB (IC50 = 292.30 ± 4.69 µg/mL and 671.11 ± 6.74 µg/mL). Whereas the grapefruit peel extracts both in ethanolic (GPE) and ethyl acetate (GPEA) have antioxidant activity in FRAP (EC50 219.47 ± 71.96 µg / ml and 309.44 ± 95.76 µg/ml) and BCB (EC50 245.19 ± 162.47 µg/ml and 567.54 ± 95.31 µg/ml). As positive standards for FRAP antioxidant analysis were quercetin and vitamin C which has IC50 respectively 18.97 ± 4.50 µg/mL and 24.47 ± 1.44 µg/mL. While in BCB analysis, Butylated Hydroxy Toluene (BHT) used as positive standard (IC50 38.68 ± 5.70 µg/mL). The samples of SE, SEA, GPE and GPEA showed tyrosinase inhibitory activity which the IC50 values were respectively 492.68 ± 1.43; 2658 ± 48.08; 3312.5 ± 222.74; 2985.17 ± 122.80 µg/ml. Kojic acid (IC50 111.52 ± 0.42 µg/ml) is used as positive standard in this study. In addition, SE, SEA, GPE and GPEA were able to inhibit elastase and collagenase enzymes, although their activities were still lower than the positive standard used in this study. Elastastinal in concentration 50 µg/mL giving elastase inhibition about 71.71 ± 0.81 µg/mL, while vitamin C in the same concentration showed collagenase inhibition about 66.79 ± 1.23 µg/mL. It can be concluded that the extract of strawberry and grapefruit peel has antioxidant, anti-tyrosinase and anti-wrinkle activity through inhibition of elastase and collagenase enzymes; thus, they can be used as antiaging cosmetic ingredients.