adsorption and release
Recently Published Documents


TOTAL DOCUMENTS

169
(FIVE YEARS 42)

H-INDEX

31
(FIVE YEARS 5)

Materials ◽  
2021 ◽  
Vol 14 (23) ◽  
pp. 7345
Author(s):  
Aleksander Ejsmont ◽  
Anna Stasiłowicz-Krzemień ◽  
Dominika Ludowicz ◽  
Judyta Cielecka-Piontek ◽  
Joanna Goscianska

Losartan potassium is most commonly used for the treatment of hypertension. In recent years, new applications of this drug have emerged, encouraging the design of novel nanoporous carriers for its adsorption and release. The purpose of this study was to synthesize ordered mesoporous carbon vehicles via a soft-templating method altered with the use of nitrogen precursors and via a hard-templating method followed by chitosan functionalization. As a result, the materials obtained differed in nitrogen content as well as in the number of total surface functional groups. The impact of the modification on the physicochemical properties of carbon carriers and their interaction with losartan potassium during adsorption and release processes was examined. The materials were characterized by various morphologies, specific surface areas (101–1180 m2 g−1), and the amount of acidic/basic oxygen-containing functional groups (1.26–4.27 mmol g−1). These features, along with pore sizes and volumes, had a key effect on the sorption capacity of carbon carriers towards losartan potassium (59–161 mg g−1). Moreover, they contributed to the differential release of the drug (18.56–90.46%). Losartan potassium adsorption onto the surface of carbonaceous materials was mainly based on the formation of hydrogen bonds and π–π interactions and followed the Langmuir type isotherm. It has been shown that the choice of the method of carbon carriers’ synthesis and their modification allows for the precise control of the kinetics of the losartan potassium release from their surface, resulting in rapid or sustained drug liberation.


2021 ◽  
Vol 22 (22) ◽  
pp. 12247
Author(s):  
Florian Olivier ◽  
Sylvie Bonnamy ◽  
Nathalie Rochet ◽  
Christophe Drouet

A biomaterial that is both bioactive and capable of controlled drug release is highly attractive for bone regeneration. In previous works, we demonstrated the possibility of combining activated carbon fiber cloth (ACC) and biomimetic apatite (such as calcium-deficient hydroxyapatite (CDA)) to develop an efficient material for bone regeneration. The aim to use the adsorption properties of an activated carbon/biomimetic apatite composite to synthetize a biomaterial to be used as a controlled drug release system after implantation. The adsorption and desorption of tetracycline and aspirin were first investigated in the ACC and CDA components and then on ACC/CDA composite. The results showed that drug adsorption and release are dependent on the adsorbent material and the drug polarity/hydrophilicity, leading to two distinct modes of drug adsorption and release. Consequently, a double adsorption approach was successfully performed, leading to a multifunctional and innovative ACC-aspirin/CDA-tetracycline implantable biomaterial. In a second step, in vitro tests emphasized a better affinity of the drug (tetracycline or aspirin)-loaded ACC/CDA materials towards human primary osteoblast viability and proliferation. Then, in vivo experiments on a large cortical bone defect in rats was carried out to test biocompatibility and bone regeneration ability. Data clearly highlighted a significant acceleration of bone reconstruction in the presence of the ACC/CDA patch. The ability of the aspirin-loaded ACC/CDA material to release the drug in situ for improving bone healing was also underlined, as a proof of concept. This work highlights the possibility of bone patches with controlled (multi)drug release features being used for bone tissue repair.


2021 ◽  
Vol 22 ◽  
Author(s):  
Cuiyan Liu ◽  
Yun Zhu ◽  
Yanfei He ◽  
Guangtai Fan ◽  
Jingang Gu ◽  
...  

Background: Carbonized herbal medicine has been used clinically for centuries in China; however, its influence on the bioavailability of compatible medicinal herbs is still unknown. Objective: To explore the effect of a carbonized herbal medicine on the in vivo adsorption and release and absorption of other active pharmaceutical ingredients in a compound prescription. Methods: The bioavailability of carbonized Herba schizonepetae (CHS) to eight active components (epiberberine, coptisine, palmatine, berberine, phellodendrine, aesculin, aesculetin, and anemoside B4) in the aqueous extract of Pulsatillae Decoction (PDAE) was evaluated by the in vitro adsorption and release and in vivo pharmacokinetics tests. Activated carbon (AC) was used as the control. Results: In vitro experiment showed that the cumulative adsorption rates of CHS to the eight active components were 33.17%, 54.32%, 21.48%, 42.01%, 39.1%, 25.11%, 32.11%, and 23.08% which was characterized by copsitine > berberine > phellodendrine > epiperberine > aesculetin > anemoside B4 > palmatine., and they were significantly lower than those of AC. The stable release concentration in sequence was 3.23, 3.04, 3.32, 7.29, 3.17, 2.80, 1.45, and 3.81 µg/mL, which was characterized by berberine > anemoside B4 > palmatine > epiberberine > phellodendrine > coptisine > aesculin > aesculetin, and they were significantly higher than those of AC. The animal experiment indicated that the areas under the concentration-time curve (AUC0-∞) of epiberberine, berberine, aesculetin, and anemoside B4 in PDAE+CHS group were significantly higher than those in the PDAE and PDAE+AC groups, and the other four components in the PDAE+CHS group were lower than those in PDAE group but higher than those in PDAE+AC group. Conclusion: CHS could significantly improve the bioavailability of epiberberine, berberine, aesculetin, and anemoside B4 in Pulsatillae Decoction and has a sustained-release effect on berberine, aesculin, aesculetin, and anemoside B4.


2021 ◽  
Vol 22 (14) ◽  
pp. 7665
Author(s):  
Cristina Carucci ◽  
Nicola Scalas ◽  
Andrea Porcheddu ◽  
Marco Piludu ◽  
Maura Monduzzi ◽  
...  

Mesoporous silica nanoparticles (MSN) were synthesised and functionalised with triethylenetetramine (MSN-TETA). The samples were fully characterised (transmission electron microscopy, small angle X-ray scattering, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and nitrogen adsorption/desorption isotherms) and used as carriers for the adsorption of the antimicrobial drug sulphamethizole (SMZ). SMZ loading, quantified by UV–Vis spectroscopy, was higher on MSN-TETA (345.8 mg g−1) compared with bare MSN (215.4 mg g−1) even in the presence of a lower surface area (671 vs. 942 m2 g−1). The kinetics of SMZ adsorption on MSN and MSN-TETA followed a pseudo-second-order model. The adsorption isotherm is described better by a Langmuir model rather than a Temkin or Freundlich model. Release kinetics showed a burst release of SMZ from bare MSN samples (k1 = 136 h−1) in contrast to a slower release found with MSN-TETA (k1 = 3.04 h−1), suggesting attractive intermolecular interactions slow down SMZ release from MSN-TETA. In summary, the MSN surface area did not influence SMZ adsorption and release. On the contrary, the design of an effective drug delivery system must consider the intermolecular interactions between the adsorbent and the adsorbate.


Ceramics ◽  
2021 ◽  
Vol 4 (2) ◽  
pp. 291-301
Author(s):  
Toshiki Miyazaki ◽  
Koudai Masuda ◽  
Kazuki Sakamoto

Calcium phosphate is attracting attention as a bone repair material and a controlled-release carrier of various drugs such as bone disease therapeutic agents and anticancer agents. Compared with some bioabsorbable polymers, calcium phosphates have the advantage of preventing a pH decrease in the surrounding body fluid. However, there are few studies comparing the effect of supporting substances with different physicochemical properties on the production of calcium phosphate microspheres with different crystalline phases. In this study, we investigated conditions for obtaining low crystallinity apatite and octacalcium phosphate (OCP) microspheres from calcium carbonate microspheres with different crystalline structures using a simple phosphoric acid treatment. Furthermore, we investigated the adsorption and release behavior of different dyes and proteins from the apatite and OCP microspheres. Overall, the factors governing the adsorption and release behavior are different depending on the molecular size and surface charge of the dye and protein adsorbates.


2021 ◽  
Vol 8 (5) ◽  
pp. 201585
Author(s):  
Sunnam Kim ◽  
Sho Moriya ◽  
Sakura Maruki ◽  
Tuyoshi Fukaminato ◽  
Tomonari Ogata ◽  
...  

In this study, three-dimensional network architectures are constructed using nano-sized graphene oxide (nGO) as the building block. The cross-linking reaction of nGO is conducted in sub-micrometre water droplets in an emulsion system to control the size of the networks by restricting the reaction space. Two types of three-dimensional GO networks with different cross-linking lengths were constructed, and their methyl orange adsorption and release behaviours were investigated under external stimuli, such as thermal treatment, ultrasonic wave treatment and near-infrared light irradiation.


Sign in / Sign up

Export Citation Format

Share Document