Treating oral diseases remains challenging as API is quickly washed out of the application site by saliva turnover and mouth movements. In situ gels are a class of application forms that present sol-gel transition's ability as a response to stimuli. Their tunable properties are provided using smart polymers responsible for stimuli sensitivity, often providing mucoadhesivity. In this study, antimicrobial in situ gels of thermosensitive and pH-sensitive polymers loaded with silver nanoparticles were prepared and evaluated. The nanoparticles were prepared by green synthesis using Agrimonia eupatoria L. extract. According to the data analysis, the in situ gel with the most promising profile contained 15 % of Pluronic® F-127, 0.25 % of methylcellulose, and 0.1 % of Noveon® AA-1. Pluronic® F-127 and methylcellulose significantly increased the viscosity of in situ gels at 37 °C and shear rates similar to speaking and swallowing. At 20 °C, a behavior close to a Newtonian fluid was observed while being easily injectable (injection force 13.455 ± 1.973 N). The viscosity of the formulation increased with temperature and reached 2962.77 ± 63.37 mPa·s (37 °C). A temperature increase led to increased adhesiveness and rigidity of the formulation. The critical sol-gel transition temperature at physiological pH was 32.65 ± 0.35 °C. 96.77 ± 3.26 % of Ag NPs were released by erosion and dissolution of the gel after 40 min. The determination of MIC showed effect against E. coli and S. aureus (0.0625 mM and 0.5000 mM, respectively). The relative inhibition zone diameter of the in situ gel was 73.32 ± 11.06 % compared to gentamicin sulfate. This work discusses the optimization of the formulation of novel antibacterial in situ gel for oromucosal delivery, analyses the impact of the concentration of excipients on the dependent variables, and suggests appropriate evaluation of the formulation in terms of its indication. This study offers a promising dosage form for local treatment of oral diseases.
Silver nanoparticles (Ag NPs) with antibacterial activity can be prepared in different ways. In our case, we used ecological green synthesis with Agrimonia eupatoria L. The plant extract was used with Ag NPs for the first time to prepare termosensitive in situ gels (ISGs). Such gels are used to heal human or animal skin and mucous membranes, as they can change from a liquid to solid state after application. Ag NPs were characterized with various techniques (FTIR, TEM, size distribution, zeta potential) and their antibacterial activity was tested against Staphylococcus aureus and Escherichia coli. In accordance with the TEM data, we prepared monodispersed spherical Ag NPs with an average size of about 20 nm. Organic active compounds from Agrimonia eupatoria L. were found on their surfaces using FTIR spectroscopy. Surprisingly, only the in situ gel with Ag NPs showed antibacterial activity against Escherichia coli, while Ag NPs alone did not. Ag NPs prepared via green synthesis using plants with medicinal properties and incorporated into ISGs have great potential for wound healing due to the antibacterial activity of Ag NPs and the dermatological activity of organic substances from plants.
- Publikační typ
- časopisecké články MeSH
Recently, the stimuli-responsive polymers get increased scientific interest due to the ability to reversibly alter their physicochemical properties. They are often referred to as smart, environmental-sensitive or intelligent polymers. This review provides fundamental information on various types of smart polymers responsive to biological, physical and chemical stimuli with examples of their use in the preparation of smart hydrogels and in situ gels with controlled or targeted drug release.
Salidroside, as a chemical compound from the group of phenylpropanoids, and rosavin are used for the standardization of dry extracts from the underground stem and root of Rhodiola rosea. In this study we monitored two different extracts from Rhodiola rosea, which differ in content of active compounds, colour, technological and physico-chemical properties (e.g. flow properties). These extracts were mixed with excipients and the flow characteristics of mixture – bulk volume and tapped volume – were determined. After formulating the tablets by compression, qualitative parameters like disintegration, resistance to crushing, friability, mass uniformity and texturometric parameters were tested. Also, dissolution profiles were evaluated using first order kinetic model, Korsmeyer-Peppas model and Weibull model for correlation. In some formulations, the impact of the properties of dry extracts on various technological properties of final tablets was more marked. We suggest that in case of a higher extract:excipients ratio, these properties manifest themselves by an even higher impact.
Transdermálne terapeutické systémy (TTS) zlepšujú komplianciu pacientov hlavne pre svoju jednoduchú aplikáciu a dlhodobé pôsobenie s nutnosťou výmeny systému každých 12 hodín až niekoľko dní. Výhodou je tiež obídenie first-pass efektu, vyhnutie sa gastrointestinálnym nežiadúcim účinkom, stabilné hladiny liečiva v krvi a jednoduché prerušenie liečby odlepením náplasti. Väčšina liečiv však nemá vhodné fyzikálno-chemické vlastnosti na to, aby sa dosiahli terapeutické hladiny pomocou transdermálnej aplikácie, preto je na trhu len obmedzené množstvo liečiv aplikovaných touto cestou. Mikroihly (MI) svojou nebolestivou aplikáciou sa javia perspektívne v zvýšení permeácie liečiva transdermálnou cestou. V tejto prehľadovej práci sú opísané rôzne typy MI (pevné, vrstvené, duté, matricové, hydrogélové), ich veľkosť, tvar, zoskupenie, ale tiež materiály a technológie, ktoré sa využívajú pri výrobe MI. V závere sa práca venuje aktuálnym klinickým štúdiám, v rámci ktorých boli využité MI. Svojimi jedinečnými vlastnosťami majú MI potenciál zvýšiť paletu transdermálne podávaných liečiv, v súčasnosti aplikovaných inou cestou podania. MI tak môžu doslova raziť cestu transdermálnej aplikácii nedostatočne penetrujúcim malým molekulám, ale aj veľkým molekulám ako vakcínam, monoklonálnym protilátkam alebo siRNA.
Transdermal Therapeutic Systems (TTS) improve patient compliance especially due to its simple application and long-term action with the need to exchange the system every 12 hours to several days. The advantages also include elimination of first-pass effect, avoidance of gastrointestinal adverse effects, stable drug levels in the blood and simple discontinuation of therapy by patch removing. However, most drugs do not have the appropriate physicochemical properties to achieve therapeutic levels by transdermal application, therefore only a limited amount of drugs administered by this route is available on the market. Microneedles (MI) by their painless application appear to increase drug permeation when applied transdermally. In this review work, various types of MI (solid, coated, hollow, matrix, hydrogel forming) their size, shape, grouping, but also materials and technologies used in MI production are described. Finally, the work is focused on current clinical trials in which MI have been tested. MI with their unique properties have potential to increase the range of transdermally administered drugs currently applied by another route of administration. MI can simply pave the way for transdermal delivery to poorly penetrating small molecules as well as large molecules such as vaccines, monoclonal antibodies, or siRNA.
- Klíčová slova
- mikrojehly,
- MeSH
- aplikace kožní * MeSH
- farmaceutická technologie metody MeSH
- klinická studie jako téma MeSH
- léčivé přípravky aplikace a dávkování MeSH
- lidé MeSH
- vakcíny aplikace a dávkování MeSH
- Check Tag
- lidé MeSH
Flow-through cell dissolution method was implemented in pharmacopoeias in 1990 and since that time its usage significantly increased. It is employed in oral dosage forms with controlled drug release to measure dissolved drug amount within particular time intervals and to characterize pure drug properties (apparent dissolution). Modified flow-through cell is used to determine the drug dissolution from lipophilic dosage forms such as suppositories and soft capsules. Recently, few modifications of this method were published in order to provide drug release studies from parenteral controlled release products and inhalation dosage forms. Review article is presenting last innovations in this area, i.e. new adjustment and arrangement of flow-through cell method, to assess drug release from implants, micro- and nanoparticulate systems, stents and inhalation medicaments in the way more corresponding to in-vivo conditions.
- Klíčová slova
- in vitro - in vivo,
- MeSH
- aplikace inhalační MeSH
- biologická dostupnost MeSH
- elektrochemické techniky * metody přístrojové vybavení využití MeSH
- farmaceutická technologie normy MeSH
- hodnocení léčiv * MeSH
- lékové formy normy MeSH
- lékové transportní systémy * MeSH
- lidé MeSH
- nanočástice MeSH
- protézy a implantáty MeSH
- referenční knihy normy MeSH
- rozpustnost * MeSH
- stenty MeSH
- Check Tag
- lidé MeSH
