scholarly journals Towards a Better Understanding of Verapamil Release from Kollicoat SR:IR Coated Pellets Using Non-Invasive Analytical Tools

Pharmaceutics ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1723
Author(s):  
Julie Fahier ◽  
Branko Vukosavljevic ◽  
Laure De Kinder ◽  
Hugues Florin ◽  
Jean-François Goossens ◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Drug Release ◽  
Fluorescence Spectroscopy ◽  
Phosphate Buffer ◽  
Crack Formation ◽  
Raman Imaging ◽  
Acetate Buffer ◽  
Film Coatings ◽  
Non Invasive ◽  
Analytical Tools

The aim of this study was to gain deeper insight into the mass transport mechanisms controlling drug release from polymer-coated pellets using non-invasive analytical tools. Pellet starter cores loaded with verapamil HCl (10% loading, 45% lactose, 45% microcrystalline cellulose) were prepared by extrusion/spheronization and coated with 5% Kollicoat SR:IR 95:5 or 10% Kollicoat SR:IR 90:10. Drug release was measured from ensembles of pellets as well as from single pellets upon exposure to acetate buffer pH = 3.5 and phosphate buffer pH = 7.4. The swelling of single pellets was observed by optical microscopy, while dynamic changes in the pH in the pellet cores were monitored by fluorescence spectroscopy. Also, mathematical modeling using a mechanistically realistic theory as well as SEM and Raman imaging were applied to elucidate whether drug release mainly occurs by diffusion through the intact film coatings or whether crack formation in the film coatings plays a role. Interestingly, fluorescence spectroscopy revealed that the pH within the pellet cores substantially differed upon exposure to acetate buffer pH = 3.5 and phosphate buffer pH = 7.4, resulting in significant differences in drug solubility (verapamil being a weak base) and faster drug release at lower pH: from ensembles of pellets and single pellets. The monitoring of drug release from and the swelling of single pellets indicated that crack formation in the film coatings likely plays a major role, irrespective of the Kollicoat SR:IR ratio/coating level. This was confirmed by mathematical modeling, SEM and Raman imaging. Importantly, the latter technique allowed also for non-invasive measurements, reducing the risk of artifact creation associated with sample cutting with a scalpel.

Formulating SLN and NLC as Innovative Drug Delivery Systems for Non-Invasive Routes of Drug Administration

2020 ◽  
Vol 27 (22) ◽  
pp. 3623-3656 ◽  
Author(s):  
Bruno Fonseca-Santos ◽  
Patrícia Bento Silva ◽  
Roberta Balansin Rigon ◽  
Mariana Rillo Sato ◽  
Marlus Chorilli
Keyword(s):  
Drug Delivery ◽  
Particle Size ◽  
Drug Release ◽  
Drug Loading ◽  
Average Particle Size ◽  
Delivery Systems ◽  
Average Particle ◽  
Minor Importance ◽  
Routes Of Administration ◽  
Non Invasive

Colloidal carriers diverge depending on their composition, ability to incorporate drugs and applicability, but the common feature is the small average particle size. Among the carriers with the potential nanostructured drug delivery application there are SLN and NLC. These nanostructured systems consist of complex lipids and highly purified mixtures of glycerides having varying particle size. Also, these systems have shown physical stability, protection capacity of unstable drugs, release control ability, excellent tolerability, possibility of vectorization, and no reported production problems related to large-scale. Several production procedures can be applied to achieve high association efficiency between the bioactive and the carrier, depending on the physicochemical properties of both, as well as on the production procedure applied. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes Lipid-based nanocarriers (LNCs) versatile delivery system for various routes of administration. The route of administration has a significant impact on the therapeutic outcome of a drug. Thus, the non-invasive routes, which were of minor importance as parts of drug delivery in the past, have assumed added importance drugs, proteins, peptides and biopharmaceuticals drug delivery and these include nasal, buccal, vaginal and transdermal routes. The objective of this paper is to present the state of the art concerning the application of the lipid nanocarriers designated for non-invasive routes of administration. In this manner, this review presents an innovative technological platform to develop nanostructured delivery systems with great versatility of application in non-invasive routes of administration and targeting drug release.

scholarly journals Non-Invasive Technical Investigation of English Portrait Miniatures Attributed to Nicholas Hilliard and Isaac Oliver

Heritage ◽  
2021 ◽  
Vol 4 (3) ◽  
pp. 1165-1181
Author(s):  
Flavia Fiorillo ◽  
Lucia Burgio ◽  
Christine Slottved Kimbriel ◽  
Paola Ricciardi
Keyword(s):  
Fluorescence Spectroscopy ◽  
Scientific Methodology ◽  
Small Scale ◽  
Artistic Practice ◽  
X Ray ◽  
Non Invasive ◽  
Miniature Painting ◽  
Entire Career ◽  
Similarities And Differences ◽  
Victoria And Albert Museum

This study presents the results of the technical investigation carried out on several English portrait miniatures painted in the 16th and 17th century by Nicholas Hilliard and Isaac Oliver, two of the most famous limners working at the Tudor and Stuart courts. The 23 objects chosen for the analysis, spanning almost the entire career of the two artists, belong to the collections of the Victoria and Albert Museum (London) and the Fitzwilliam Museum (Cambridge). A non-invasive scientific methodology, comprising of stereo and optical microscopies, Raman microscopy, and X-ray fluorescence spectroscopy, was required for the investigation of these small-scale and fragile objects. The palettes and working techniques of the two artists were characterised, focusing in particular on the examination of flesh tones, mouths, and eyes. These findings were also compared to the information written in the treatises on miniature painting circulating during the artists’ lifetime. By identifying the materials and techniques most widely employed by the two artists, this study provides information about similarities and differences in their working methods, which can help to understand their artistic practice as well as contribute to matters of attribution.

scholarly journals Characterization and Identification of Varnishes on Copper Alloys by Means of UV Imaging and FTIR

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 298
Author(s):  
Miriam Truffa Giachet ◽  
Julie Schröter ◽  
Laura Brambilla
Keyword(s):  
Copper Alloys ◽  
Analytical Techniques ◽  
Experimental Methodology ◽  
Artificial Ageing ◽  
Non Invasive ◽  
Uv Imaging ◽  
Before And After ◽  
The Comparative Study ◽  
The 19Th Century ◽  
Analytical Tools

The application of varnishes on the surface of metal objects has been a very common practice since antiquity, both for protective and aesthetic purposes. One specific case concerns the use of tinted varnishes on copper alloys in order to mimic gilding. This practice, especially flourishing in the 19th century for scientific instruments, decorative objects, and liturgical items, results in large museum collections of varnished copper alloys that need to be preserved. One of the main challenges for conservators and restorers deals with the identification of the varnishes through non-invasive and affordable analytical techniques. We hereby present the experimental methodology developed in the framework of the LacCA and VERILOR projects at the Haute École ARC of Neuchâtel for the identification of gold varnishes on brass. After extensive documentary research and analytical campaigns on varnished museum objects, various historic shellac-based varnishes were created and applied by different methods on a range of brass substrates with different finishes. The samples were then characterized by UV imaging and infrared spectroscopy before and after artificial ageing. The comparative study of these two techniques was performed for different thicknesses of the same varnish and for different shellac grades in order to implement an identification methodology based on simple non-invasive examination and analytical tools, which are accessible to conservators.

scholarly journals Non-invasive, real-time reporting drug release in vitro and in vivo

2015 ◽  
Vol 51 (32) ◽  
pp. 6948-6951 ◽  
Author(s):  
Yanfeng Zhang ◽  
Qian Yin ◽  
Jonathan Yen ◽  
Joanne Li ◽  
Hanze Ying ◽  
...  
Keyword(s):  
Drug Release ◽  
Real Time ◽  
Near Infrared ◽  
Reporting System ◽  
Real Time Monitoring ◽  
Near Infrared Fluorescence ◽  
Non Invasive ◽  
Fluorescence Dye

Anin vitroandin vivodrug-reporting system is developed for real-time monitoring of drug release via the analysis of the concurrently released near-infrared fluorescence dye.

scholarly journals Assessment of physical and dissolution characteristics of various itraconazole capsule formulations: a comparative analysis

2019 ◽  
Vol 5 (4) ◽  
pp. 765
Author(s):  
Rajan Verma ◽  
Shrikant Hodge ◽  
Chandrashekhar Gargote ◽  
Prakash Modi ◽  
Naresh Upreti ◽  
...  
Keyword(s):  
Size Distribution ◽  
Phosphate Buffer ◽  
Acetate Buffer ◽  
Simulated Gastric Fluid ◽  
Physical Parameters ◽  
Dissolution Profile ◽  
Lauryl Sulfate ◽  
Complete Dissolution ◽  
Innovator Product

<p class="abstract"><strong>Background:</strong> This <em>in vitro</em> study compared physical parameters and the dissolution profile of innovator itraconazole capsule formulation, i-Tyza, and 5 other generic capsule formulations available in the Indian market.</p><p class="abstract"><strong>Methods:</strong> The number of pellets and size distribution were determined using naked eye examination and sieving method, respectively. Dissolution profile of formulations was done at 15, 30, 45, and 60 minutes, using a United States Pharmacopeia type II Paddle apparatus in simulated gastric fluid (SGF, pH 1.2) without enzymes, acetate buffer (pH 4.5) with 0.5% sodium lauryl sulfate (SLS), and phosphate buffer (pH 6.8) with 0.5% SLS.<strong></strong></p><p class="abstract"><strong>Results:</strong> All formulations had capsule size 0. Capsule fill weight (~335 to ~510 mg) and total pellet number (127 to 810) varied across formulation, with the innovator brand having the highest number of pellets. Innovator product and i-Tyza had similar fill weight (~460 mg). Pellet size distribution of the innovator product, brand 2, brand 3, and i-Tyza was relatively narrow. In SGF, except brand 1 (84% dissolved) and brand 5 (80% dissolved), all the formulations had near-complete (&gt;85% drug dissolved) or complete dissolution (&gt;90% drug dissolved) at 60 minutes. In acetate buffer, pH 4.5 with 0.5% SLS and phosphate buffer, pH 6.8 with 0.5% SLS, only the innovator product and i-Tyza demonstrated near-complete to complete dissolution at 60 minutes (96% and 90% dissolved).</p><p class="abstract"><strong>Conclusions:</strong> Across all the itraconazole generic formulations evaluated, i-Tyza had comparable physical characteristics and dissolution profile to the innovator product. The <em>in vitro</em> dissolution profile of i-Tyza may indicate adequate <em>in vivo</em> performance.</p>

scholarly journals Effect of nonionic surfactants on the release of paracetamol from suppositories

2015 ◽  
Vol 26 (1) ◽  
pp. 40-44
Keyword(s):  
Drug Release ◽  
Physical Properties ◽  
Phosphate Buffer ◽  
Nonionic Surfactants ◽  
Tween 80 ◽  
Content Uniformity ◽  
Fusion Method ◽  
Disintegration Time ◽  
Span 60

The preparation suppositories contain 250 mg of paracetamol on different bases using Novata BD, Novata BCF and composition of Novata BCF/BD (1:1). Suppositories were prepared by the fusion method. The prepared formulations with or without surfactants (Tween 80, Span 60) at concentrations of 2% and 4% (w/w) were tested for hardness, to tal time of de for ma tion, disintegration time, content uniformity and release of the drug. The release of the drug was carried in the apparatus with the stirrer shade in phosphate buffer (pH 7.2) at 100 rpm. The physical properties of the prepared suppositories were according with the requirement of Polish Pharmacopoeia 9th edition. Addition of 4 % Tween 80 to suppository bases significantly increased the drug release from all the investigated formulations. However, incorporation of Span 60 did not result in improvement of the drug release significantly.

scholarly journals Carbon-Based Magnetic Nanocarrier for Controlled Drug Release: A Green Synthesis Approach

2018 ◽  
Vol 5 (1) ◽  
pp. 1 ◽  
Author(s):  
Jessica Oliveira ◽  
Raquel Rodrigues ◽  
Lillian Barros ◽  
Isabel Ferreira ◽  
Luís Marchesi ◽  
...  
Keyword(s):  
Drug Delivery ◽  
Magnetic Nanoparticles ◽  
Drug Release ◽  
Phosphate Buffer ◽  
Colloidal Stability ◽  
Ph Dependence ◽  
Phosphate Buffer Solution ◽  
Controlled Drug Release ◽  
Buffer Solution ◽  
Carbon Based

In this study, hydrophilic magnetic nanoparticles were synthesized by green routes using a methanolic extract of Rubus ulmifolius Schott flowers. The prepared magnetic nanoparticles were coated with carbon-based shell for drug delivery application. The nanocomposites were further chemically functionalized with nitric acid and, sequentially, with Pluronic® F68 (CMNPs-plur) to enhance their colloidal stability. The resulting material was dispersed in phosphate buffer solution at pH 7.4 to study the Doxorubicin loading. After shaking for 48 h, 99.13% of the drug was loaded by the nanocomposites. Subsequently, the drug release was studied in different working phosphate buffer solutions (i.e., PB pH 4.5, pH 6.0 and pH 7.4) to determine the efficiency of the synthesized material for drug delivery as pH-dependent drug nanocarrier. The results have shown a drug release quantity 18% higher in mimicking tumor environment than in the physiological one. Therefore, this study demonstrates the ability of CMNPs-plur to release a drug with pH dependence, which could be used in the future for the treatment of cancer "in situ" by means of controlled drug release.

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