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1.
Int J Biol Macromol ; 257(Pt 1): 128502, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38040139

RESUMO

As a natural raw material to replace synthetic chemicals, cellulose and its derivatives are the most popular choices in the pharmaceutical industry. For drug delivery applications, cellulose is usually used as a cellulose nanocrystal (CNC). CNC-based hydrogels are widely utilized for drug delivery because drug molecules can be encapsulated in their pore-like structures. This study aims to develop CNC hydrogels for the delivery of doripenem antibiotics. CNC was obtained from jackfruit peel extraction, and alginate was used as a network polymer to produce hydrogels. Ionotropic gelation was used in the synthesis of CNC-alginate hydrogel composites. The maximum adsorption of doripenem by CNC was 65.7 mg/g, while the maximum adsorption by CNC-alginate was 98.4 mg/g. One of the most challenging aspects of drug delivery is predicting drug release from a solid matrix using simple and complex mathematical equations. The sigmoidal equation could represent the doripenem release from CNC, while the Ritger-Peppas equation could describe the doripenem release from CNC-Alginate. The biocompatibility testing of CNC and CNC-alginate against a 7F2 cell line indicates that both materials were non-toxic.


Assuntos
Artocarpus , Nanopartículas , Hidrogéis/química , Celulose/química , Doripenem , Alginatos/química , Adsorção , Nanopartículas/química
2.
Front Chem Sci Eng ; : 1-21, 2023 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-37359292

RESUMO

The Association of Southeast Asian Nations is blessed with agricultural resources, and with the growing population, it will continue to prosper, which follows the abundance of agricultural biomass. Lignocellulosic biomass attracted researchers' interest in extracting bio-oil from these wastes. However, the resulting bio-oil has low heating values and undesirable physical properties. Hence, co-pyrolysis with plastic or polymer wastes is adopted to improve the yield and quality of the bio-oil. Furthermore, with the spread of the novel coronavirus, the surge of single-use plastic waste such as disposable medical face mask, can potentially set back the previous plastic waste reduction measures. Therefore, studies of existing technologies and techniques are referred in exploring the potential of disposable medical face mask waste as a candidate for co-pyrolysis with biomass. Process parameters, utilisation of catalysts and technologies are key factors in improving and optimising the process to achieve commercial standard of liquid fuel. Catalytic co-pyrolysis involves a series of complex mechanisms, which cannot be explained using simple iso-conversional models. Hence, advanced conversional models are introduced, followed by the evolutionary models and predictive models, which can solve the non-linear catalytic co-pyrolysis reaction kinetics. The outlook and challenges for the topic are discussed in detail.

3.
Environ Res ; 224: 115550, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36841526

RESUMO

Pyrolysis oil from oil palm biomass can be a sustainable alternative to fossil fuels and the precursor for synthesizing petrochemical products due to its carbon-neutral properties and low sulfur and nitrogen content. This work investigated the effect of applying mesoporous acidic catalysts, Ni-Mo/TiO2 and Ni/Al2O3, in a catalytic co-pyrolysis of oil palm trunk (OPT) and polypropylene (PP) from 500 to 700 °C. The obtained oil yields varied between 12.67 and 19.50 wt.% and 12.33-17.17 wt.% for Ni-Mo/TiO2 and Ni/Al2O3, respectively. The hydrocarbon content in oil significantly increased up to 54.07-58.18% and 37.28-68.77% after adding Ni-Mo/TiO2 and Ni/Al2O3, respectively. The phenolic compounds content was substantially reduced to 8.46-20.16% for Ni-Mo/TiO2 and 2.93-14.56% for Ni/Al2O3. Minor reduction in oxygenated compounds was noticed from catalytic co-pyrolysis, though the parametric effects of temperature and catalyst type remain unclear. The enhanced deoxygenation and cracking of phenolic and oxygenated compounds and the PP decomposition resulted in increased hydrocarbon production in oil during catalytic co-pyrolysis. Catalyst addition also promoted the isomerization and oligomerization reactions, enhancing the formation of cyclic relative to aliphatic hydrocarbon.


Assuntos
Polipropilenos , Pirólise , Titânio , Hidrocarbonetos , Catálise , Biomassa , Biocombustíveis , Temperatura Alta
4.
Int J Clin Pract ; 75(12): e15012, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34806816

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has infected millions of people around the world, with most cases recorded among adults. The cases reported among children have been acknowledged to be minimal in comparison to adults. Nevertheless, coronavirus disease 2019 (COVID-19) has been reported to affect children of all ages, including newborns. The symptoms among children have also been identified to be similar to those observed among adults, although paediatric patients have been noted to display a spectrum of clinical features ranging from asymptomatic to moderate symptoms. Despite ample publications on the ongoing pandemic, the literature is only replete with guidelines on treating SARS-CoV-2 infection among older people. In this narrative review, comprehensive updates on the infection in children have been discussed. The latest information on the spread of the disease among children around the world, the clinical features observed among the paediatric population, as well as recommended pharmaceutical treatments of COVID-19 among this special group of patients have been covered. Further, expert consensus statements regarding the management of this highly contagious disease among pregnant women and neonates have been discussed. It is believed that this comprehensive review will provide updated information on the epidemiology and clinical features of the ongoing pandemic among paediatric patients. Additionally, the guidelines for handling SARS-CoV-2 among pregnant women and children, as reviewed in this article, are anticipated to be useful to frontline clinicians battling this fatal disease around the globe.


Assuntos
COVID-19 , Adulto , Idoso , Criança , Feminino , Humanos , Recém-Nascido , Pandemias , Gravidez , SARS-CoV-2
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