177,117 research outputs found
Recycling within the Chemical Industry: The Circular Economy Era
No full textIn this present work, we have briefly discussed the importance of recycling within the chemical sector. Recycling is fundamental in promoting a circular economy, which is a new paradigm of sustainability that is able to reduce environmental implications, and in creating new business opportunities. Therefore, to highlight the importance of recycling in the circular economy era, we have reported on some recent examples of strategies helpful to minimize waste by increasing the efficiency of the whole system and promoting a greener/safer chemical industry
Dextran and its potential use as tablet excipient
No full textDextrans are a class of carbohydrate polymers extensively applied in pharmaceutical applications, particularly as drug conjugate macromolecular carriers or drug delivery systems. These polysaccharides improve the stability of the therapeutics enabling also the control of their release, via either the parenteral and or oral routes. In the latter case, due to their gel forming ability they may have potential as hydrophilic matrix tablets for sustained drug release.
In this paper, we investigated the behaviour of different molecular weight (1, 40, 500 and 2300 kDa) dextrans as tabletting excipients. Powder particle size and hygroscopic studies have been reported, together with tabletability, tablet stability and tablet swelling. Moreover we use tramadol as model compound to evaluate the ability of dextrans to control drug dissolution. The results suggest that dextrans with lower molecular weights may be a promising excipient to be used as filler for immediate release tablets, due to their good tabletability and fast dissolution rate, while dextrans with higher molecular weights could be an efficient disintegrant due to their swelling ability
Environmental certifications and programs roadmap for a sustainable chemical industry
No full textMeeting public demands for benign chemistry will require companies to develop holistic approaches that manage chemicals from three different perspectives that focus on the organization, its products, or specific chemical materials. A more collaborative approach to chemical management will depend on building trust among a diverse group of stakeholders with often conflicting objectives
Sustainable by design approaches
No full textNon richiesto, articolo editoriale di apertura di un virtual special issu
Oral drug therapy in elderly with dysphagia: between a rock and a hard place!
No full textSerena Logrippo,1,2 Giovanna Ricci,3 Matteo Sestili,4 Marco Cespi,2 Letizia Ferrara,4 Giovanni F Palmieri,2 Roberta Ganzetti,4 Giulia Bonacucina,2 Paolo Blasi2 1School of Advanced Studies, 2School of Pharmacy, 3School of Law, University of Camerino, Camerino, 4Italian National Research Centers on Ageing (INRCA), Ancona, Italy Abstract: Demographic indicators forecast that by 2050, the elderly will account for about one-third of the global population. Geriatric patients require a large number of medicines, and in most cases, these products are administered as solid oral solid dosage forms, as they are by far the most common formulations on the market. However, this population tends to suffer difficulties with swallowing. Caregivers in hospital geriatric units routinely compound in solid oral dosage forms for dysphagic patients by crushing the tablets or opening the capsules to facilitate administration. The manipulation of a tablet or a capsule, if not clearly indicated in the product labeling, is an off-label use of the medicine, and must be supported by documented scientific evidence and requires the patient’s informed consent. Compounding of marketed products has been recognized as being responsible for an increased number of adverse events and medical errors. Since extemporaneous compounding is the rule and not the exception in geriatrics departments, the seriousness and scope of issues caused by this daily practice are probably underestimated. In this article, the potential problems associated with the manipulation of authorized solid oral dosage forms are discussed. Keywords: geriatric medicine, dysphagia, compounding, modified-release formulations, gastrointestinal tract toxicit
Hydrogen from Renewables: A Case Study of Glycerol Reforming
No full textBiomass is an interesting candidate raw material for the production of renewable hydrogen. The conversion of biomass into hydrogen can be achieved by several processes. In particular, this short review focuses on the recent advances in glycerol reforming to hydrogen, highlighting the development of new and active catalysts, the optimization of reaction conditions, and the use of non-innocent supports as advanced materials for supported catalysts. Different processes for hydrogen production from glycerol, especially aqueous phase reforming (APR) and steam reforming (SR), are described in brief. Thermodynamic analyses, which enable comparison with experimental studies, are also considered. In addition, research advances in terms of life cycle perspective applied to support R&D activities in the synthesis of renewable H2 from biomass are presented. Lastly, also featured is an evaluation of the studies published, as evidence of the increased interest of both academic research and the industrial community in biomass conversion to energy sources
Doxorubicin loaded liposomes in hydrogels: rheological properties and drug release profiles
No full textHydrogels are versatile formulations that have gained over years a large attention for a wide range of applications in different health-related fields such as tissue engineering, regenerative medicine and drug delivery [1]. In drug delivery, hydrogels were widely investigated as aqueous formulations able to control the release of the drugs and active substances, entrapped inside their 3D network [2]. Diffusion, erosion or swelling-controlled mechanisms are well-known for several polymeric and fibrillary cross-linked networks, and many works have focused on how the hydrogel cross-linking is able to govern the release profile [3]. However, scarce information is available for the release of drugs loaded inside liposomes, which are incorporated inside a hydrogel. The so called “liposomes-in-hydrogel” formulations have been developed to sustain drug release longer at the administration site [4,5], but at which extent the liposomes membrane and the cross-linked network can have an impact on the drug release, it has not been fully elucidated. Therefore, the aim of the present work is to investigate the release properties of hydrogel systems incorporating doxorubicin (DOX)-loaded liposomes. For this purpose, different systems were prepared by thickening the commercial liposomal dispersion Doxil® (DOX encapsulation efficiency >95%) with hydroxypropylmethyl cellulose (HPMC) K4M and K100 types at the concentration of 2% w/w and Carbopol® 974 at the concentration of 0.5% w/w. Systems were prepared starting from Doxil® liposomal dispersion to have a final formulation, in which almost all drug (DOX used as a model) is initially encapsulated inside liposomes and it is not present in a free form inside the hydrogel network. Polymers (HPMC K4M, HPMC K100 and Carbopol® 974) were selected according to their different thickening potency and ability to form cross-linked systems in water.
All prepared systems were characterised in terms of rheology by stress and frequency sweep test. Release studies were conducted at 37°C using as medium a 150 mM ammonium chloride buffer at pH 5.5 and 6.5, according to the “dialysis membrane” (using a Type II dissolution apparatus) or the ultracentrifugation method. The release properties of the liposomal dispersions were also investigated as a control. The release amount of DOX was quantified by UV-spectroscopy at 488 nm.
The incorporation of DOX-loaded liposomes into HPMC-based hydrogels did not affect the rheological properties in terms of consistency and viscoelasticity. On the other side, the incorporation of DOX-loaded liposomes into Carbopol ® 974 based hydrogels led to a slight decrease in consistency without affecting the viscoelastic properties of the system. DOX release was strongly dependent from pH. Indeed, drug is release faster from liposomes at pH 6.5 than pH 5.5, reaching the 70% and 30% of drug release, respectively, after 48 hours. This effect was observed both for the liposomal dispersion and all the liposomes-incorporating hydrogels. Moreover, DOX release was also found dependent on the viscosity of the hydrogel. Specifically, less drug was released from the hydrogel having a higher consistency, as those prepared using HPMC K100 and Carbopol® 974 with the respect to those prepared with HPMC K4M at both tested pH values. However, the effect of the polymeric matrix in controlling the release is more evident at pH 6.5 than at pH 5.5 for all systems, since at a higher pH the passage of the drug across the liposomal membrane is favourite and a larger amount of drug is released from the core of the liposomes inside the matrix. A clear effect exerted by the different polymer was also observed for the hydrogel loaded with DOX as a free drug, used as a reference. By comparing the two release methods investigated (i.e. dialysis membrane and ultracentrifugation) for the liposomes incorporating hydrogels, a higher release was achieved using the ultracentrifugation since the formulation was in direct contact with the release medium, thereby better promoting the polymeric matrix dissolution.
In conclusions, the release profiles of DOX are controlled by both the liposomal membrane and the polymeric matrix, as a function of the different diffusion rate of the drug across the phospholipid bilayer and the swelled hydrogel.
References
[1] Correa S. et al, Chem. Rev. 121, 18 (2021)
[2] Li J. and Mooney D.J. Nat. Rev. Mater 16071, (2016)
[3] Elsawy M.A. al, Biomacromolecules 23, 6 (2022)
[4] Hurler J. et al. Int. J. Pharm. 456, (2013)
[5] Billard A. et al, Carbohydr. Polym. 115, (2015
LCA integration within sustainability metrics for chemical companies
No full textThe application of a life-cycle perspective within the industrial sector may help companies in supporting all the planning activities aimed to promote new business opportunities. The usage of LCA is a common practice in corporates working in the field of chemistry. The development and production of fine/bulk chemicals, pharmaceuticals, plastics, personal care products, etc., may be supported by LCA and green metrics. The development of a lower impact and safer chemical industry is encouraged by the adoption of the Green Chemistry principles. Among these the usage of renewables sources of building blocks is one of the most investigated principle. However, the use of biomass as starting precursors needs to be assessed through LCA before considering a bio-based route greener than the traditional fossil pathway. Recently, the social sphere of sustainability has increased its importance also in the chemical industry, because many chemicals could have social repercussions as a consequence of their adoption. The implementation of S-LCA strategies may help enterprises to configure repercussions of their activities in this sense, by achieving SDGs described in the Agenda 2030. This chapter is intended to drive readers through such issues by stimulating their sensibility towards sustainability within the chemical industry
Beyond the beaker: benign by design society
No full textIn this work we discuss the necessity for Green Chemistry & Green Engineering to look out of the laboratory and consider the social aspects with greater attention to pursue peace and equality
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