Rita Aquino - Academia.edu (original) (raw)

Papers by Rita Aquino

Gels

The production of aerogels for different applications has been widely known, but the use of polys... more The production of aerogels for different applications has been widely known, but the use of polysaccharide-based aerogels for pharmaceutical applications, specifically as drug carriers for wound healing, is being recently explored. The main focus of this work is the production and characterization of drug-loaded aerogel capsules through prilling in tandem with supercritical extraction. In particular, drug-loaded particles were produced by a recently developed inverse gelation method through prilling in a coaxial configuration. Particles were loaded with ketoprofen lysinate, which was used as a model drug. The core-shell particles manufactured by prilling were subjected to a supercritical drying process with CO2 that led to capsules formed by a wide hollow cavity and a tunable thin aerogel layer (40 μm) made of alginate, which presented good textural properties in terms of porosity (89.9% and 95.3%) and a surface area up to 417.0 m2/g. Such properties allowed the hollow aerogel parti...

International Journal of Pharmaceutics

Proceedings of the 2nd World Congress on Recent Advances in Nanotechnology, Mar 1, 2023

RNA interference is a technique to induce specific gene silencing, mediated by siRNAs, double str... more RNA interference is a technique to induce specific gene silencing, mediated by siRNAs, double stranded RNA molecules (19-27 bp) that induce specific mRNA degradation in the cytoplasm [1]. Despite the immense therapeutic potentiality, siRNAs suffer of poor stability in vivo and almost zero uptake by cells due to high molecular weight, hydrophilicity and the presence of negative charges [2]. Polyplexes, colloidal systems originated from the electrostatic interaction between negative nucleic acids and positive charged polymers, emerged as one of the most versatile systems for nucleic acid delivery Our current research focuses on the generation of libraries of graft semisynthetic polycations with multiple architectures and analogue composition, starting from Inulin (INU), a natural polysaccharide, to explore how the structure of the carrier influences the delivery process. Inulin is constituted by a PEG backbone from which one fructose ring per repeating unit is hanging. It has already been investigated as scaffold for the design of siRNA vectors [3][4] and as PEG alternative in amphiphilic derivatives for nanocostruction [5]. Contrarily to PEG, INU has the advantage of being natural, non-immunogenic and functionalizable along its entire length, allowing the modulation of composition and architecture in a smooth way. In this contribution we present the first derivatives of the serie INU-PEI: Inulin-g-branched polyethyleneimine (INU-bPEI) and its amphiphilic analogue INU-bPEI-PLA. Derivatives with two different derivatization degree in PEI were tested to prepare copolymer/siRNA polyplexes by interpolyelectrolytic interactions. Agarose gel retardation assay showed that this new copolymers were able to stop the electrophoretic run of siRNA. Complexes were characterized by DLS studies and by stability studies in the presence of albumin. Our investigation showed the ability of this systems to resist to the anionic exchange. In addition, haemocompatibility of polyplexes was demonstrated. This early results encourage us to continue in this study to obtain efficient inulin based siRNA delivery systems.

Applied Sciences

A new polymeric construct is proposed as a starting material for a liver-targeted delivery system... more A new polymeric construct is proposed as a starting material for a liver-targeted delivery system in the present communication. The polymeric material has been designed to be sensitive to pH variations and potentially loaded with hydrophobic antitumoral agents. It is based on one of the most used copolymers in the field of nanomedicine: PEG-PLA. The latter, usually obtained by polymerization of lactic acid on the hydroxyl-terminated polyether, is assembled by the pH-reversible condensation between a phenylboronic acid-ended methoxy PEG 2000 (MeO-PEG2000-PBA) and a galactose-capped PLA of 1–10 kDa (PLA-Gal). Our approach is based on the strategic assumption that would allow a new ligand presentation strategy in which Gal is both a structural element for the stimulus-responsive PEG de-shielding and the targeting moiety. Indeed, Gal has a vicinal diol able to form a reversible boronate ester with a B(OH) 2 residue, which is cleavable at the acidic pH of the tumor microenvironment, and ...

Molecules

Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a d... more Novel additive manufacturing (AM) techniques and particularly 3D printing (3DP) have achieved a decade of success in pharmaceutical and biomedical fields. Highly innovative personalized therapeutical solutions may be designed and manufactured through a layer-by-layer approach starting from a digital model realized according to the needs of a specific patient or a patient group. The combination of patient-tailored drug dose, dosage, or diagnostic form (shape and size) and drug release adjustment has the potential to ensure the optimal patient therapy. Among the different 3D printing techniques, extrusion-based technologies, such as fused filament fabrication (FFF) and semi solid extrusion (SSE), are the most investigated for their high versatility, precision, feasibility, and cheapness. This review provides an overview on different 3DP techniques to produce personalized drug delivery systems and medical devices, highlighting, for each method, the critical printing process parameters,...

Italian journal of anatomy and embryology, 2015

Cystic fibrosis (CF) is a genetic life-shortening condition in Caucasians. Despite being a multi-... more Cystic fibrosis (CF) is a genetic life-shortening condition in Caucasians. Despite being a multi-organ disease, CF is classically diagnosed by symptoms of acute/chronic respiratory disease, with persistent pulmonary infections (Amaral, 2015). CF is caused by mutations in the gene encoding cystic fibrosis transmembrane conductance regulator (CFTR) protein. Inheritance of mutant CFTR alleles results in surface liquid depletion and defective mucociliary clearance leading to pulmonary failure. Defects in CFTR perturb the regulation of many intracellular signaling pathways including the NF-kB pathway causing excessive production of pro-inflammatory mediators. Current CF therapies are directed to delay CF lung damage by restoring CFTR function and controlling abnormal inflammation. However, only few anti-inflammatory drugs are effective for CF treatments (mainly oral corticosteroids and ibuprofen), these drugs have limited beneficial effects in presence of considerable side effects. Flavo...

Pharmaceutics, 2021

The study focused on the development and characterization of an O/W emulsion for skincare contain... more The study focused on the development and characterization of an O/W emulsion for skincare containing Castanea sativa spiny burs extract (CSE) as functional agent. The emulsion was stable and had suitable physicochemical and technological properties for dermal application and CSE showed no cytotoxicity in spontaneously immortalized keratinocytes (HaCaT) at active concentrations. A single-blind, placebo-controlled, monocentric study was designed to evaluate the skin tolerability and the skin performance of the CSE-loaded emulsion on healthy human volunteers. An improvement was observed in skin biomechanical properties such as hydration, skin elasticity and a reduction in the periorbital wrinkles in 30 days without altering the skin barrier function, sebum, pH, and erythema values. A significant skin moisturizing effect was detected while the skin barrier function was preserved. The selected natural ingredient combined with the designed formulation and the optimized preparation method ...

European Journal of Pharmaceutics and Biopharmaceutics, 2019

Strategies to load prednisolone or dexamethasone in preformed poly(L-lactic acid) (PLA) filaments... more Strategies to load prednisolone or dexamethasone in preformed poly(L-lactic acid) (PLA) filaments and 3D printed scaffolds were explored as a way of personalizing the drug, the dose and the release profile for regenerative medicine purposes. Instead of starting from a PLA filament preloaded with a given content of drug, we explored two more versatile strategies. The first one involved the soaking of PLA filaments into a drug solution prepared in a solvent that reversibly swelled PLA; during 3D printing the melting of PLA contributed to the efficient integration (encapsulation) of the drug inside the printed strand. The second strategy consisted in first printing the 3D PLA scaffolds followed by soaking in a suitable drug solution in order to exploit the higher specific surface of the printed strands compared to the filament. Sustained release profiles were recorded when either prednisolone or dexamethasone were loaded in preformed PLA filaments, while rapid release was recorded for 3D PLA scaffolds loaded after printing. The combination of the two proposed methods reported here opened the possibility of creating concentration gradients of different drugs in the same scaffold exhibiting distinct release patterns. Namely, the strand core contained an active ingredient to be slowly released, while the surface was covered with other active ingredient that could be rapidly delivered. The feasibility of this approach was confirmed through dual loading of dexamethasone in 2 the filament and of prednisolone on the preformed scaffold. Drug-loaded scaffolds were characterized in terms of printability, structural characteristics (DSC, XRD), mechanical properties, biodegradation, and ability to promote cell attachment and proliferation. Finally, anti-inflammatory response and osteoinductive properties were verified in cell cultures.

Molecules (Basel, Switzerland), Jan 14, 2018

Many natural compounds having antioxidant and anti-inflammatory activity are a potential target f... more Many natural compounds having antioxidant and anti-inflammatory activity are a potential target for new therapies against chronic inflammatory syndromes. The oral administration of functional herbal supplements may become a prevention strategy or therapy adjuvant for susceptible patients. A case study is our milk thistle () extract rich in silymarin complex. A water-soluble microencapsulated powder system was developed by a spray drying technique to improve the poor silymarin bioactivity after oral administration. Sodium carboxymethylcellulose (NaCMC) was employed as coating/swelling polymer matrix and sodium lauryl sulfate (SLS) as the surfactant (1:1:0.05 //). A H₂O/EtOH/acetone (50/15/35 //) solvent system was used as liquid feed. The microsystems were capable of improving the in vitro dissolution and permeation rates, suggesting an enhancement of bioactivity after oral administration. The microsystems protect the antioxidant activity of silymarin after harsh storage conditions p...

Recent Advances in Novel Drug Carrier Systems, 2012

Besides chronic bacterial infections, chronic airway inflammation is uniformly observed in patien... more Besides chronic bacterial infections, chronic airway inflammation is uniformly observed in patients with CF [9, 10], as a consequence of over-expression of proinflammatory enzymes. Thus, the lung, dipped in an environment rich in oxygen as well as a defective antioxidant system, is susceptible to injury mediated by oxidative stress. Reactive oxygen species, ROS, such as super oxide anion (O 2 •-) and hydroxyl radical (OH •), and reactive nitrogen species, RNS, such as nitrogen dioxide and peroxynitrite, are unstable molecules with unpaired electrons, capable of initiating oxidation. In order to prevent tissue damage, lungs are endowed with several antioxidant defences, including glutathione, heme oxygenase, superoxide dismutase, vitamins C and E, beta-carotene, uric acid [11]. However, when the presence of ROS and RNS overcomes the physiologic antioxidant defences, an oxidative stress status, occurs. Thus, as an adjunct to optimal antibiotic therapy, antioxidant/anti-inflammatory therapy is warranted to avoid a decline in lung function and tissue damage.

Pharmaceutics

Background: Almond skins are rich in bioactive compounds that undergo oxidation/degradation pheno... more Background: Almond skins are rich in bioactive compounds that undergo oxidation/degradation phenomena and are poorly soluble in water, reducing in vivo absorption and bioavailability, factors that influence the pharmacological activity of an active product. We developed a dried acetonic almond skins extract/cyclodextrin complex to improve extract solubility, dissolution rate and biological activity. Methods: A lyophilized acetonic almond skin extract was produced. To optimize complex formulation, phase solubility studies and complex characterization (absorption studies, differential scanning calorimetry (DSC), morphology, solubility studies) were performed. To evaluate a possible use in healthy products, tumor necrosis factor-α levels and reactive oxygen species release, as well as cicloxygenase-2 and inducible nitric oxide synthase expression in intestinal epithelial cells, were also evaluated. Results: Phase solubility studies showed a Bs-type profile. A 1:1 dried acetonic almond ...

Life

The National Institute of Health has reported that approximately 80% of chronic infections are as... more The National Institute of Health has reported that approximately 80% of chronic infections are associated with biofilms, which are indicated as one of the main reasons for bacteria’s resistance to antimicrobial agents. Several studies have revealed the role of N-acetylcysteine (NAC), in reducing biofilm formation induced by different microorganisms. A novel mixture made up of NAC and different natural ingredients (bromelain, ascorbic acid, Ribes nigrum, resveratrol, and pelargonium) has been developed in order to obtain a pool of antioxidants as an alternative strategy for biofilm reduction. The study has demonstrated that the mixture is able to significantly enhance NAC activity against different Gram-positive and Gram-negative bacteria. It has shown an increase in NAC permeation in vitro through an artificial fluid, moving from 2.5 to 8 μg/cm2 after 30 min and from 4.4 to 21.6 μg/cm2 after 180 min, and exhibiting a strongly fibrinolytic activity compared to the single components o...

Women's Health Research, 2018

Supercritical Assisted Atomization (SAA) has been successfully used for the production of polymer... more Supercritical Assisted Atomization (SAA) has been successfully used for the production of polymer-drug microspheres for controlled release. Recently this technique has been proposed for the production of microspheres where bovine serum albumin (BSA) was used as carrier for several anti-inflammatory drugs. In this work the production of BSA/pectin (PC)/gentamicin sulfate (GS) microsphere is presented and the effect of drug/BSA/PC ratio on the release behaviour of GS is investigated. Size distribution and shape factor of the microspheres were determined by SEM image and laser scattering analysis. Drug release profiles were measured by Franz diffusion cell system using PBS buffer as acceptor solution. Microspheres produced by SAA showed a mean diameter between 1.5 μm and 2.0 μm, depending on the drug/polymers ratio used to produce the particles; particularly, the higher was the ratio the smaller was the mean diameter. All the microparticles exhibited very high loading capacity, with an encapsulation efficiency of about 100%. Drug release curves showed a prolonged release of GS depending on the drug/polymers ratio. Indeed, the higher was the quantity of BSA/PC mixture used to manufacture the microparticles the longer was the release of GS encapsulated