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1.
Sci Rep ; 13(1): 11792, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37479792

RESUMO

An in-line smartphone connected to a screen-printed selective electrode hand-held device was used to determine the concentration of distigmine bromide (DB) in its pure and dosage forms as well as its degradation kinetics by continuously measuring the change in the produced emf over time. The main objective, supported by the data presented, is to produce a highly reliable smartphone integrated selective sensor as a portable analyzer with potential high cloud connectivity combining a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles. The choice of ionophore used in this approach was guided by computation and the data obtained was compared with traditional analytical techniques. DB, for which there are no previously reported stability-indicating methods and for which four novel such methods are proposed here, was selected as a model drug for this work. At-line UV-spectrophotometry DB assay was obtained by measuring the difference between the spectra of the degradation product and the same concentration of intact drug. The degradation kinetics were studied by this method through tracking the decrease of DB absorbance and/or the increase of a generated degradation product signal over time. Off-line separation based HPLC and TLC stability-indicating methods for DB were also presented. All methods employed in this work were validated for accuracy, precision, specificity, repeatability, linearity, range, detection and quantification limits according to the ICH guidelines and were applied to the analysis of laboratory prepared mixtures as well as commercial products. While all methods proposed were shown to be highly reliable, the smartphone integrated selective sensor is highlighted as a portable analyzer with potential high cloud connectivity and was shown to combine a wide linear dynamic range, the fastest response time with the lowest limits of detection and quantitation while best integrating green analytical chemistry principles.


Assuntos
Bioensaio , Química Analítica , Cinética , Eletrodos , Preparações Farmacêuticas
2.
Molecules ; 28(3)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36770815

RESUMO

The dramatic rise in cancer incidence, alongside treatment deficiencies, has elevated cancer to the second-leading cause of death globally. The increasing morbidity and mortality of this disease can be traced back to a number of causes, including treatment-related side effects, drug resistance, inadequate curative treatment and tumor relapse. Recently, anti-cancer bioactive peptides (ACPs) have emerged as a potential therapeutic choice within the pharmaceutical arsenal due to their high penetration, specificity and fewer side effects. In this contribution, we present a general overview of the literature concerning the conformational structures, modes of action and membrane interaction mechanisms of ACPs, as well as provide recent examples of their successful employment as targeting ligands in cancer treatment. The use of ACPs as a diagnostic tool is summarized, and their advantages in these applications are highlighted. This review expounds on the main approaches for peptide synthesis along with their reconstruction and modification needed to enhance their therapeutic effect. Computational approaches that could predict therapeutic efficacy and suggest ACP candidates for experimental studies are discussed. Future research prospects in this rapidly expanding area are also offered.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Antineoplásicos/química , Neoplasias/tratamento farmacológico , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Peptídeos/química
3.
Talanta ; 132: 52-8, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25476278

RESUMO

Propantheline bromide (PB) is a hydrolysable anti-cholinergic drug. A novel strategy for the online monitoring of PB degradation kinetics catalysed by hydroxyl ions is presented. This is achieved by the incorporation of an on-site PB-selective electrode constructed using as an ionophore. This sensor was used to track the hydrolysis of PB by continuous measurement of the decrease in the produced emf over time. The use of this new technique provides real-time observation and yields a continuous profile of the hydrolysis behaviour of PB under various pH conditions as well as the temperature dependency of each reaction. Moreover, a great advantage of this proposed on-line system is its higher accuracy for rate constant estimation relative to other off-line methods. This kinetic data analysis permitted the determination of the hydrolysis activation energy and prediction of the drug shelf life. The estimated activation energy from Arrhenius plot was 20.77 kcal mol(-1).


Assuntos
Calixarenos/química , Ionóforos/química , Antagonistas Muscarínicos/análise , Sistemas On-Line/instrumentação , Potenciometria/instrumentação , Propantelina/análise , Soluções Tampão , Estabilidade de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Hidrólise , Eletrodos Seletivos de Íons , Cinética , Potenciometria/métodos , Soluções , Temperatura , Termodinâmica
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