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1.
BioTech (Basel) ; 12(2)2023 May 03.
Article in English | MEDLINE | ID: covidwho-2326920

ABSTRACT

Immobilized metal affinity chromatography (IMAC) is a popular and valuable method for the affinity purification of polyhistidine-tagged recombinant proteins. However, it often shows practical limitations, which might require cumbersome optimizations, additional polishing, and enrichment steps. Here, we present functionalized corundum particles for the efficient, economical, and fast purification of recombinant proteins in a column-free format. The corundum surface is first derivatized with the amino silane APTES, then EDTA dianhydride, and subsequently loaded with nickel ions. The Kaiser test, well known in solid-phase peptide synthesis, was used to monitor amino silanization and the reaction with EDTA dianhydride. In addition, ICP-MS was performed to quantify the metal-binding capacity. His-tagged protein A/G (PAG), mixed with bovine serum albumin (BSA), was used as a test system. The PAG binding capacity was around 3 mg protein per gram of corundum or 2.4 mg per 1 mL of corundum suspension. Cytoplasm obtained from different E. coli strains was examined as examples of a complex matrix. The imidazole concentration was varied in the loading and washing buffers. As expected, higher imidazole concentrations during loading are usually beneficial when higher purities are desired. Even when higher sample volumes, such as one liter, were used, recombinant protein down to a concentration of 1 µg/mL could be isolated selectively. Comparing the corundum material with standard Ni-NTA agarose beads indicated higher purities of proteins isolated using corundum. His6-MBP-mSA2, a fusion protein consisting of monomeric streptavidin and maltose-binding protein in the cytoplasm of E. coli, was purified successfully. To show that this method is also suitable for mammalian cell culture supernatants, purification of the SARS-CoV-2-S-RBD-His8 expressed in human Expi293F cells was performed. The material cost of the nickel-loaded corundum material (without regeneration) is estimated to be less than 30 cents for 1 g of functionalized support or 10 cents per milligram of isolated protein. Another advantage of the novel system is the corundum particles' extremely high physical and chemical stability. The new material should be applicable in small laboratories and large-scale industrial applications. In summary, we could show that this new material is an efficient, robust, and cost-effective purification platform for the purification of His-tagged proteins, even in challenging, complex matrices and large sample volumes of low product concentration.

2.
TrAC - Trends in Analytical Chemistry ; 162 (no pagination), 2023.
Article in English | EMBASE | ID: covidwho-2293300

ABSTRACT

Biomarker detection has attracted increasing interest in recent years due to the minimally or non-invasive sampling process. Single entity analysis of biomarkers is expected to provide real-time and accurate biological information for early disease diagnosis and prognosis, which is critical to the effective disease treatment and is also important in personalized medicine. As an innovative single entity analysis method, nanopore sensing is a pioneering single-molecule detection technique that is widely used in analytical bioanalytical fields. In this review, we overview the recent progress of nanopore biomarker detection as new approaches to disease diagnosis. In highlighted studies, nanopore was focusing on detecting biomarkers of different categories of communicable and noncommunicable diseases, such as pandemic COVID-19, AIDS, cancers, neurologic diseases, etc. Various sensitive and selective nanopore detecting strategies for different types of biomarkers are summarized. In addition, the challenges, opportunities, and direction for future development of nanopore-based biomarker sensors are also discussed.Copyright © 2023 Elsevier B.V.

3.
Journal of Building Engineering ; 72, 2023.
Article in English | Scopus | ID: covidwho-2290595

ABSTRACT

Stepping up the extraction of valuable resources from the oil palm agro-industry was fraught with palm kernel shell (PKS) disposal challenges. One mitigating measure was to recover these materials for use in fired brick production. So PKS and clay materials were characterized for their physical, mineral and thermal properties. These characterizations revealed the high content of SiO2 and Al2O3 in the clay resources and the 95.60% organic content of PKS along with its estimated 21, 774.94 (kJ/kg) higher heating value (HHV). Indexed minerals from X-ray diffraction (XRD) studies of the clay material were kaolinite, quartz, calcite and goethite. Bricks prepared with the inclusion of up to 16 wt% PKS were fired at 900 and 1000 °C. For bricks fired at 1000 °C, bulk densities decreased from 2.07 to 1.54 g/cm3, apparent porosity increased up to 89.14%, water absorption increased from 100% in reference bricks to 203.54% with the addition of 16 wt% PKS. While compressive strengths decreases were in the range of 21.67–6.07 MPa, thermal insulation improved by 22%. Similar trends were established for bricks fired at 900 °C. The analyses showed that PKS addition was more effective in tailoring the technical properties of the bricks than changes in firing temperature. The marginal differences in technical properties of bricks fired at 1000 °C relative to the 900 °C fired brick units were understood from scanning electron microscopy (SEM) studies. Therefore, this research has provided compelling evidences for use of PKS in fired brick production. © 2023 Elsevier Ltd

4.
Chemical Engineering Journal ; 463:N.PAG-N.PAG, 2023.
Article in English | Academic Search Complete | ID: covidwho-2298968

ABSTRACT

• Pd/ m- Al 2 O 3 -Si catalyst exhibited high efficiency in converting α- amino -ε- caprolactam (α- ACL) to dimethyl-protected cyclic lysine (DMCL). • The lack of Brönsted acid sites on Pd/ m- Al 2 O 3 -Si surface facilitated the formation of DMCL and suppressed undesirable reaction process. • Pd/ m- Al 2 O 3 -Si catalyst with microspherical morphology performed excellent stability and physical strength during the catalytic process. • The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited a great potential in the synthesis of self-cleaning antibacterial materials. Antibacterial monomers are prerequisites for synthesizing antibacterial polymers, especially during the current COVID-19 pandemic. Dimethyl-protected cyclic lysine (DMCL) is a promising functional monomer for nylon-6 based self-cleaning antibacterial polymers. However, the production of DMCL still faces formidable challenges, such as harsh reaction conditions and low catalyst activities. In this study, we developed a Pd/ m -Al 2 O 3 -Si catalyst, which exhibited high efficiency in converting α -amino- ε -caprolactam (α -ACL) to DMCL, affording a yield of as high as 97.1% at 100 °C and 1 MPa H 2. The lack of Brönsted acid sites on the catalyst surface facilitated the formation of DMCL and suppressed undesirable hydrolysis or cracking by-products from the lactam-based reactant. The recycled experiments showed that Pd/ m -Al 2 O 3 -Si performed excellent stability and physical strength with essentially no damage to its microspheres after the reaction. The nylon‑6 copolymers produced from the as-synthesized DMCL exhibited similar structure and thermal stability with pure nylon-6, showing great potential in synthesizing the self-cleaning antibacterial polymers. This work provides a sustainable and efficient method for producing DMCL and other lysine-based antibacterial monomers, showing a great prospect for the utilization of bio-based chemicals in synthesizing functional polymers. [ FROM AUTHOR] Copyright of Chemical Engineering Journal is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

5.
Journal of the Energy Institute ; 108, 2023.
Article in English | Scopus | ID: covidwho-2296574

ABSTRACT

Millions of face mask has been converted to waste since the onset of COVID-19 virus. Hence, present study explores the feasibility of converting disposable face masks to energy through catalytic pyrolysis process using a low-cost waste (spent aluminum hydroxide/oxide nanoparticle adsorbent) derived catalyst. Thermogravimetric analysis of the non-catalytic and catalytic pyrolysis of disposable face mask was conducted at varied heating rates of 10 °C/min, 20 °C/min, 30 °C/min, 40 °C/min, and 50 °C/min, respectively. Iso-conversional methods, Kissinger Akahira Sunose (KAS) and Ozawa Flynn Wall (OFW) were used for the kinetic study. The reaction mechanism was analyzed using Criado's z-master plot (CZMP) method along with the determination of thermodynamic parameters of the process. Results found that the addition of a catalyst to the process benefits the overall efficacy of the process by reducing the activation energy (Ea) (without catalyst;OFW-Ea: 188.7 kJ/mol, KAS-Ea: 186.2 kJ/mol) as well as lowering the disordered state of the process. Metal doped catalyst (Ni/ γ-Al2O3) (OFW-Ea: 168.4 kJ/mol, KAS-Ea: 167.8 kJ/mol) shows a larger reduction in activation energy in comparison to bare alumina (γ-Al2O3) (OFW-Ea: 183.2 kJ/mol, KAS-Ea: 180.4 kJ/mol). The current study presented disposable face masks as reclaimable in terms of energy and waste-derived catalyst as a potent solution to be explored in place of high-cost commercial catalysts. © 2023 Energy Institute

6.
Advanced Materials Technologies ; 2023.
Article in English | Scopus | ID: covidwho-2253439

ABSTRACT

The COVID-19 pandemic, which began in 2019, has highlighted the importance of testing and tracking infected individuals as a means of mitigating the spread of the virus. In this context, the development of sensitive and rapid methods for the detection of SARS-CoV-2, the virus responsible for COVID-19, is crucial. Here, a biosensor based on oligonucleotide-gated nanomaterials for the specific detection of SARS-CoV-2 spike protein is presented. The sensing system consists of a nanoporous anodic alumina disk loaded with the fluorescent indicator rhodamine B and capped with a DNA aptamer that selectively binds the SARS-CoV-2 spike protein. The system is initially evaluated using pseudotype virus systems based on vesicular stomatitis virus carrying different SARS-CoV-2 S-proteins on their surface. When the pseudotype virus is present, the cap of the solid is selectively removed, triggering the release of the dye from the pore voids to the medium. The nanodevice demonstrated its ability to detect pseudotype virus concentrations as low as 7.5·103 PFU mL. In addition, the nanodevice is tested on nasopharyngeal samples from individuals suspected of having COVID-19. © 2023 The Authors. Advanced Materials Technologies published by Wiley-VCH GmbH.

7.
Materials (Basel) ; 16(3)2023 Jan 21.
Article in English | MEDLINE | ID: covidwho-2276635

ABSTRACT

Reanodizing metal underlayers through porous anodic alumina has already been used extensively to fabricate ordered columns of different metal oxides. Here, we present similar 3D multilayered nanostructures with unprecedented complexity. Two-level 3D column-like nanofilms have been synthesized by anodizing an Al/Nb metal layer in aqueous oxalic acid for forming the first level, and an Al/Ta layer in aqueous tartaric acid for forming the second level of the structure. Both levels were then reanodized in aqueous boric acid. The Ta layer deposited on partially dissolved porous anodic alumina of the first level, with protruding tops of niobia columns, acquired a unique hexagonally-packed structure. The morphology of the first and second levels was determined using scanning electron microscopy. Prolonged etching for 24 h in a 50%wt aqueous phosphoric acid was used to remove the porous anodic alumina. The formation mechanism of aluminum phosphates on the second-level columns in the process of long-time cold etching is considered. The model for the growth of columns on a Ta hexagonally-packed structure of the second level is proposed and described. The described approach can be applied to create 3D two- or three-level column-like systems from various valve metals (Ta, Nb, W, Hf, V, Ti), their combinations and alloys, with adjustable column sizes and scaling. The results of optical simulation show a high sensitivity of two-level column-like 3D nanofilms to biomedical objects and liquids. Among potential applications of these two-level column-like 3D nanofilms are photonic crystals for full-color displays, chemical sensors and biosensor, solar cells and thermoresponsive shape memory polymers.

8.
2022 Ural-Siberian Conference on Computational Technologies in Cognitive Science, Genomics and Biomedicine, CSGB 2022 ; : 300-303, 2022.
Article in English | Scopus | ID: covidwho-2051954

ABSTRACT

As preventive, curative and restorative measures in modern conditions of the spread of infectious diseases (Covid 19), the use of sorption materials and detoxification methods with their use in hemosorption are of particular importance. It is known that hemosorption is an effective method of detoxification of the body, and no less important is the use of safe sorbents in relation to the shaped elements of blood, both time-tested sorbents and new, less studied, but more promising from the point of view of their safe production technology. The purpose of this work is to study with the help of scanning flow cytometry the effect of a sorbent with carbon nanofiber A1203@PDMS/CNF in comparison with a carbon-free sorbent A1203@PDMS on morphofunctional parameters erythrocytes. The study of the physico-chemical properties of sorbents was carried out according to standard methods. The biological properties of sorbents were evaluated by its effect on erythrocytes of erythrocyte concentrate during hemoperfusion of blood through columns with sorbents using the method of scanning flow cytometry according to the standard method. The data obtained using the method of scanning flow cytometry made it possible to conclude that the studied sorbents do not have a traumatic effect on the morphofunctional parameters of erythrocytes. The introduction of carbon nanofiber into the composition of the sorbent in an amount of 0.02% improves the functional parameters of blood erythrocytes both in comparison with the initial donor blood and compared to the sorbent without carbon. © 2022 IEEE.

9.
Food Research ; 6(4):304-311, 2022.
Article in English | EMBASE | ID: covidwho-2044348

ABSTRACT

COVID-19 pandemic encourages the utilization of local food sources to ensure food availability. Busil (Xanthosoma sagittifolium) was readily available and affordable in Banjarnegara Regency in the Province of Central Java in Indonesia. However, the busil starch utilization was still rare due to the low functional properties of the native busil starch. The objective of this study was to explore busil starch physicochemical characterization enhancement after microwave irradiation treatment, especially on the stability of heat processing. This research was conducted in two steps. First, microwave treatment (with a variation of energy and irradiation time) of native busil starch (NBS), and the second was modified busil starch (MBS) physicochemical characterization. A rise in amylose was observed on MBS. SEM analysis was shown MBS granules are breakdown. Through viscosity, final viscosity, setback viscosity, peak time, and the pasting temperature of MBS generally were increased. Meanwhile, peak viscosity and breakdown viscosity of MBS was decreased. Thermal properties of MBS like onset (To), peak (Tp), and conclusion (Tc) temperatures were also increased. The degree of whiteness index (DW) of MBS was decreased. FTIR analysis has shown that microwave treatment did not cause functional group alteration. XRD analysis has also demonstrated no change in the diffraction pattern but a slight change in the crystallinity index. Generally, microwave treatment leads to MBS thermal stability and potentially broaden MBS utilization on food processing product.

10.
Nanomaterials (Basel) ; 12(15)2022 Jul 29.
Article in English | MEDLINE | ID: covidwho-1994123

ABSTRACT

The work introduces a localized surface plasmon resonance (LSPR) sensor chip integrated with vertical-cavity surface-emitting lasers (VCSELs). Using VCSEL as the light source, the hexagonal gold nanoparticle array was integrated with anodic aluminum oxide (AAO) as the mask on the light-emitting end face. The sensitivity sensing test of the refractive index solution was realized, combined with microfluidic technology. At the same time, the finite-difference time- domain (FDTD) algorithm was applied to model and simulate the gold nanostructures. The experimental results showed that the output power of the sensor was related to the refractive index of the sucrose solution. The maximum sensitivity of the sensor was 1.65 × 106 nW/RIU, which gives it great application potential in the field of biomolecular detection.

11.
Sustainability ; 14(13):7913, 2022.
Article in English | ProQuest Central | ID: covidwho-1934242

ABSTRACT

Indagation in the sphere of nanoparticle utilisation has provided commendatory upshots in discrete areas of application varying from medicinal use to environmental degradation alleviation. This study incorporates alumina nanoparticles as additives to diesel and biodiesel blends. The prime objective of the present study was the scrutinisation of the denouement of Al2O3 nanoparticle incorporation in diesel–biodiesel blends on a diesel engine’s performance and emission characteristics. Test fuel samples were prepared by blending different proportions of biodiesel and dispersing two concentrations of alumina nanoparticles (25 and 50 ppm) in the diesel. Dispersion was made without the use of a nanoparticle stabiliser to meet real-world feasibility. High-speed shearing was employed to blend the biodiesel and diesel, while nanoparticles were dispersed in the blends by ultrasonication. The blends so devised were tested using a single-cylinder diesel engine at fixed RPM and applied load for three compression ratios. Upshots of brake-specific fuel consumption (BSFC) and brake thermal efficiency (BTE) for fuel samples were measured with LabView-based software, whereas CO emissions and unburnt hydrocarbon (UBHC) emissions were computed using an external gas analyser attached to the exhaust vent of the engine. Investigation revealed that the inclusion of Al2O3 nanoparticles culminates in the amelioration of engine performance along with the alleviation of deleterious exhaust from engine. Furthermore, the incorporation of alumina nanoparticles assisted in the amelioration of dwindled performance attributed to biodiesel blending. More favourable results of nanoparticle inclusion were obtained at higher compression ratios compared to lower ones. Reckoning evinced that the Al2O3 nanoparticle is a lucrative introduction for fuels to boost the performance and dwindle the deleterious exhaust of diesel engines.

12.
Journal of the American College of Cardiology ; 79(9):2570, 2022.
Article in English | EMBASE | ID: covidwho-1768645

ABSTRACT

Background: The mRNA COVID vaccine is a rare cause of myocarditis in young patients. We describe a case of cardiogenic shock with extensive workup ruling out COVID vaccine induced myocarditis. Case: 42-year-old female who drinks 5 Monster energy drinks and 3-4 cups of coffee daily presented to the hospital with palpitations two weeks following her mRNA COVID vaccine. EKG showed atrial tachycardia with heart rates of 160 beats per minute. Adenosine and Lopressor were administered resulting in hemodynamic instability requiring norepinephrine. An echocardiogram showed dilated cardiomyopathy with ejection fraction of 15%. Right heart catheterization was performed, and the cardiac index was 1.22 L/min/m², systemic vascular resistance was 1918 dynes*sec*cm-5 and wedge pressure was 31 mm Hg. The patient was started on nitroprusside, furosemide, and milrinone drips and she began to improve. The patient was adamant the vaccine is what triggered her heart failure and extensive testing was performed to rule out COVID vaccine induced myocarditis. Workup showed normal coronary arteries and no evidence of infiltrative disease or myocarditis on cardiac MRI. The etiology was from tachycardia induced cardiomyopathy triggered by excessive stimulants and the patient had successful atrial tachycardia ablation of the right superior pulmonary vein. She was discharged on medical therapy for heart failure and advised to stop drinking energy drinks. Decision-making: Once the patient did not respond to the rate controlling agents an echocardiogram showed reduced ejection fraction. Right heart catheterization confirmed cardiogenic shock and nitroprusside and milrinone were started to help reduce afterload and improve contractility. Workup to exclude COVID induced myocarditis lead to the diagnosis of tachycardia induced cardiomyopathy and atrial tachycardia ablation was performed. Conclusion: We report a case of cardiogenic shock with workup diagnosing tachycardia induced cardiomyopathy induced from a combination of excessive monster energy drinks and coffee. She was treated successfully with afterload reduction, inotrope support, and atrial tachycardia ablation.

13.
17th IEEE International Conference on Group IV Photonics, GFP 2021 ; 2021-December, 2021.
Article in English | Scopus | ID: covidwho-1705808

ABSTRACT

Concentrations down to 300 pM of the interleukin-6 biomarker, identified as an inflammatory marker for severe COVID-19 infection, have been detected in buffer using referenced microring resonators in the emerging Al2O3 integrated photonic platform. Antifouling was achieved by applying an Xantec HC1000M hydrogel. © 2021 IEEE.

14.
International Journal of Computer Applications in Technology ; 66(3-4):260-266, 2021.
Article in English | ProQuest Central | ID: covidwho-1643298

ABSTRACT

The present paper focuses on wire electric discharge machine in a COVID-19 environment. It can be considered as an attempt to develop models of response variables, using different liquids, one of which is nanoparticle (Al2O3), in the use of a ratio of (2 mg) and the function of comparison. In both cases they are the rate of material removing, in the wire electric discharge machine process using the response surface methodology. The pilot plan is based on the concept of the Box-Behnken, and the study conveys the six main parameters. To evaluate the value of the advanced model, ANOVA was applied;the test results support the validity and suitability of the advanced RSM model. Optimum settings for the parameters are improved work safety in COVID-19 environments.

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