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1.
Sci Rep ; 12(1): 9394, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35672337

RESUMO

Lipid nanoparticle (LNP) technology has become extremely demanding for delivering RNA-products and other drugs. However, there is no platform to manufacture pharmaceutical-grade LNPs with desired particle size from a wide range in continuous mode. We have developed a unique platform to obtain any specific size-range of LNPs from 60 to 180 nm satisfying pharmaceutical regulatory requirements for polydispersity index, sterility, dose uniformity and bio-functionality. We applied design of experiment (DoE) methodology and identified the critical process parameters to establish the process for global application. Cross-point validation within the response map of DoE confirmed that the platform is robust to produce specific size (± 10 nm) of LNPs within the design-range. The technology is successfully transformed to production scale and validated. Products from R&D, pilot and production batches for a candidate SARS-CoV-2 mRNA-vaccine generated equivalent biological responses. The data collectively established the robustness and bio-uniformity of doses for global RNA-vaccine/drug formulation.


Assuntos
COVID-19 , Nanopartículas , COVID-19/prevenção & controle , Humanos , Lipossomos , RNA Interferente Pequeno , SARS-CoV-2/genética
2.
Environ Sci Pollut Res Int ; 29(8): 10871-10893, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34997495

RESUMO

Tin oxide (SnO2) with versatile properties is of substantial standing for practical application, and improved features of the material are demonstrated in the current issue through the integration of nanotechnology with bio-resources leading to what is termed as biosynthesis of SnO2 nanoparticles (NPs). This review reveals the recent advances in biosynthesis of SnO2 NPs by chemical precipitation method focused on distinct methodologies, characterization, and reaction mechanism along with a photocatalytic application for dye degradation. According to available literature reviews, numerous bio-based precursors selectively extracted from biological substrates have effectively been applied as capping or reducing agents to achieve the metal oxide NPs. The major precursor obtained from the aqueous extract of root barks of Catunaregam spinosa is found to be 7-hydroxy-6-methoxy-2H-chromen-2-one that has been proposed as a model compound for the reduction of metal ions into nanoparticles due to having highly active functional groups, being abundant in plants (67.475 wt%), easy to extract, and eco benign. In addition, the photocatalytic activity of SnO2 NPs for the degradation of organic dyes, pharmaceuticals, and agricultural contaminants has been discussed in the context of a promising bio-reduction mechanism of the synthesis. The final properties are supposed to depend exclusively upon a number of factors, e.g., particle size (< 50 nm), bandgap (< 3.6 eV), crystal defects, and catalysts dosage. With this contribution, it has been perceived not only to provide an overview of recent advances in the biosynthesis of SnO2 NPs but also to indicate the main issues in need aiming to show vision towards innovative outcomes.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Catálise , Precipitação Química , Compostos de Estanho
3.
J Nanosci Nanotechnol ; 20(9): 5916-5927, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32331197

RESUMO

Glycerol electro-oxidation offers a green route to produce the high value added chemicals. Here in, we report the glycerol electro-oxidation over a series of multi walled carbon nano tubes supported monometallic (Pt/CNT and Pd/CNT) and bimetallic (Pt-Pd/CNT) catalysts in alkaline medium. The cyclic voltammetry, linear sweep voltammetry and chronoamperometry measurements were used to evaluate the activity and stability of the catalysts. The Pt-Pd/CNT electrocatalyst exhibited the highest activity in terms of higher current density (129.25 A/m²) and electrochemical surface area (382 m²/g). The glycerol electro-oxidation products formed at a potential of 0.013 V were analyzed systematically by high performance liquid chromatography. Overall, six compounds were found including mesoxalic acid, 1,3-dihydroxyacetone, glyceraldehyde, glyceric acid, tartronic acid and oxalic acid. A highest mesoxalic acid selectivity of 86.42% was obtained for Pt-Pd/CNT catalyst while a maximum tartronic acid selectivity of 50.17% and 46.02% was achieved for Pd/CNT and Pt/CNT respectively. It was found that the introduction of Pd into Pt/CNT lattice facilitated the formation of C3 products in terms of maximum selectivity achieved (86.42%) while the monometallic catalysts (Pd/CNT and Pt/CNT) showed a poor performance in comparison to their counterpart.

4.
Biotechnol Lett ; 39(1): 13-23, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27659031

RESUMO

Microbial oils are considered as alternative to vegetable oils or animal fats as biodiesel feedstock. Microalgae and oleaginous yeast are the main candidates of microbial oil producers' community. However, biodiesel synthesis from these sources is associated with high cost and process complexity. The traditional transesterification method includes several steps such as biomass drying, cell disruption, oil extraction and solvent recovery. Therefore, direct transesterification or in situ transesterification, which combines all the steps in a single reactor, has been suggested to make the process cost effective. Nevertheless, the process is not applicable for large-scale biodiesel production having some difficulties such as high water content of biomass that makes the reaction rate slower and hurdles of cell disruption makes the efficiency of oil extraction lower. Additionally, it requires high heating energy in the solvent extraction and recovery stage. To resolve these difficulties, this review suggests the application of antimicrobial peptides and high electric fields to foster the microbial cell wall disruption.


Assuntos
Biocombustíveis/microbiologia , Microalgas/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Biomassa , Eletroporação , Esterificação/fisiologia , Microalgas/efeitos dos fármacos , Microalgas/genética
5.
Bioprocess Biosyst Eng ; 37(11): 2353-9, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24879090

RESUMO

This paper demonstrates Pseudomonas cepacia lipase catalyzed hydrolysis of p-nitrophenyl palmitate under irradiation of light with wavelengths of 250-750 nm. The reaction follows Michaelis-Menten Kinetics and the light irradiation increases the overall rate of hydrolysis. Using Lineweaver-Burk plot K M and V max values for the reaction in presence of light are found to be 39.07 and 66.67 mM/min/g, respectively; while for the same reaction under dark condition, the values are 7.08 and 10.21 mM/min/g. The linear form of enzyme dependent rate of reaction confirms that no mass-transfer limitations are present and the reaction is a kinetically controlled enzymatic reaction.


Assuntos
Burkholderia cepacia/enzimologia , Enzimas Imobilizadas/metabolismo , Lipase/metabolismo , Palmitatos/metabolismo , Bioengenharia , Catálise , Enzimas Imobilizadas/efeitos da radiação , Hidrólise , Cinética , Luz , Lipase/efeitos da radiação , Redes e Vias Metabólicas
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