Search results for "CARRIERS"
showing 10 items of 391 documents
Coupling of the antiviral agent zidovudine to polyaspartamide and in vitro drug release studies.
1998
A macromolecular prodrug of the known antiretroviral agent zidovudine and alpha, beta-poly(N-2-hydroxyethyl)-DL-aspartamide (PHEA) was synthesized. A succinic spacer was present between the polymer and the drug, and 1,1'-carbonyldiimidazole was used as the coupling agent. In vitro drug release studies at pH 1.1, 5.5 and 7.4 indicated that limited amounts of intact drug were released from the conjugate. At pH 1.1 and 7.4 succinylzidovudine was released, and this was hydrolysed to give free zidovudine. In the presence of alpha-chymotrypsin, zidovudine was released preferentially in comparison with the succinyl derivative. The amounts of released zidovudine and succinylzidovudine were greater …
Entrapment of an EGFR inhibitor into nanostructured lipid carriers (NLC) improves its antitumor activity against human hepatocarcinoma cells
2014
Background: In hepatocellular carcinoma (HCC), different signaling pathways are de-regulated, and among them, the expression of the epidermal growth factor receptor (EGFR). Tyrphostin AG-1478 is a lipophilic low molecular weight inhibitor of EGFR, preferentially acting on liver tumor cells. In order to overcome its poor drug solubility and thus improving its anticancer activity, it was entrapped into nanostructured lipid carriers (NLC) by using safe ingredients for parenteral delivery. Results: Nanostructured lipid carriers (NLC) carrying tyrphostin AG-1478 were prepared by using the nanoprecipitation method and different matrix compositions. The best system in terms of mean size, PDI, zeta…
PLGA nanoparticles are effective to control the colonic release and absorption on ibuprofen.
2018
The oral controlled release (CR) formulations have become more important in recent years. Among them, the polymeric nanoparticles have been thoroughly studied during the last decades, consequently they are extensively employed for a broad range of applications and drugs. The objective of this research was to develop polymeric nanoparticles (NPs) of ibuprofen with poly(lactic-co-glycolic) acid (PLGA) as polymer, and to test their applicability for oral CR formulations development. Different proportions of drug/polymer were employed to develop the ibuprofen NPs and their in vitro release profiles were analysed. The in situ segmental permeability of ibuprofen was tested in Wistar rat and demon…
From In Silico to Experimental Validation: Tailoring Peptide Substrates for a Serine Protease.
2020
Smart nanocarriers for the transport of drugs to tumor cells are nowadays of great interest for treating cancer. The use of enzymatic stimuli to cleave peptide-based drug nanocapsules for the selective release of nanocapsule cargo in close proximity to tumor cells opens new possibilities in cancer research. In the present work, we demonstrate a methodology for finding and optimizing cleavable substrate sequences by the type II transmembrane serine protease hepsin, which is highly overexpressed in prostate cancer. The design and screening of combinatorial libraries in silico against the binding cavity of hepsin allow the identification of a panel of promising substrates with high-calculated …
Solid lipid nanoparticles containing tamoxifen characterization and in vitro antitumoral activity.
2005
Solid lipid nanoparticles (SLNs) containing tamoxifen, a nons- teroidal antiestrogen used in breast cancer therapy, were prepared by microemulsion and precipitation techniques. Tamoxifen loaded SLNs seem to have dimensional properties useful for parenteral administration, and in vitro plasmatic drug release studies demon- strated that these systems are able to give a prolonged release of the drug in the intact form. Preliminary study of antiproliferative ac- tivity in vitro, carried out on MCF-7 cell line (human breast cancer cells), demonstrated that SLNs, containing tamoxifen showed an antitumoral activity comparable to free drug. The results of char- acterization studies and of in vitro …
Nanocarriers for optimizing the balance between interfollicular permeation and follicular uptake of topically applied clobetasol to minimize adverse …
2015
The treatment of various hair disorders has become a central focus of good dermatologic patient care as it affects men and women all over the world. For many inflammatory-based scalp diseases, glucocorticoids are an essential part of treatment, even though they are known to cause systemic as well as local adverse effects when applied topically. Therefore, efficient targeting and avoidance of these side effects are of utmost importance. Optimizing the balance between drug release, interfollicular permeation, and follicular uptake may allow minimizing these adverse events and simultaneously improve drug delivery, given that one succeeds in targeting a sustained release formulation to the hair…
Novel inulin-based mucoadhesive micelles loaded with corticosteroids as potential transcorneal permeation enhancers
2017
In this work a new copolymer of inulin (INU) derivatized with ethylendiamine (EDA) and retinoic acid (RA), named INU-EDA-RA, was synthetized, characterized and employed to produce micelles as carriers for topical administration of corticosteroids for the potential treatment of diseases of posterior eye segment. Spectroscopic analysis confirmed a molar derivatization degree of 11.30 and 4.30% in EDA and RA, respectively. INU-EDA-RA micelles are capable of strong mucoadhesive interactions which result time-independent and stable over time but concentration depending. Moreover micelles are able to encapsulate efficiently from 3 to 13% (w/w) of lipophilic drugs, as dexamethasone, triamcinolone …
Calixarene: A Versatile Material for Drug Design and Applications
2016
The therapy of various diseases by the drugs entrapped in calixarene derivatives is gaining attraction of researchers nowadays. Calixarenes are macrocyclic nano-baskets which belong to cavitands class of host-guest chemistry. They are the marvelous hosts with distinct hydrophobic three dimensional cavities to entrap and encapsulate biologically active guest drugs. Calixarene and its derivatives develop inclusion complexes with various types of drugs and vitamins for their sustained/targeted release. Calixarene and its derivatives are used as carriers for anti-cancer, anti-convulsant, anti-hypertensive, anthelmentic, anti-inflammatory, antimicrobial and antipsychotic drugs. They are the impo…
Fully degradable protein nanocarriers by orthogonal photoclick tetrazole-ene chemistry for the encapsulation and release
2020
The encapsulation of sensitive drugs into nanocarriers retaining their bioactivity and achieving selective release is a challenging topic in current drug delivery design. Established protocols rely on metal-catalyzed or unspecific reactions to build the (mostly synthetic) vehicles which may inhibit the drug's function. Triggered by light, the mild tetrazole–ene cycloaddition enables us to prepare protein nanocarriers (PNCs) preserving at the same time the bioactivity of the sensitive antitumor and antiviral cargo Resiquimod (R848). This catalyst-free reaction was designed to take place at the interface of aqueous nanodroplets in miniemulsion to produce core–shell PNCs with over 90% encapsul…
Nanocarriers for respiratory diseases treatment: Recent advances and current challenges
2014
Pulmonary delivery of locally-acting drugs encapsulated in nanocarriers provides several advantages for the treatment of respiratory diseases such as asthma, chronic obstructive pulmonary diseases, cystic fibrosis, tuberculosis and lung cancer. These advantages include, among others, sustained drug delivery to the lungs, reduced therapeutic dose and improved patient compliance. The aim of this review is to give an updated overview on recent advances recorded in the last few years in this field as well as on the major challenges still existing and that remain to be overcome before any clinical application. After an outline on the cellular and extracellular barriers affecting drug delivery to…