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Fürst A, Kali G, Dizdarević A, Stengel D, Bernkop-Schnürch A. Mucoadhesive polymers: Design of S-protected thiolated cyclodextrin-based hydrogels. Int J Pharm 2024; 656:124075. [PMID: 38599445 DOI: 10.1016/j.ijpharm.2024.124075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/19/2024] [Accepted: 03/30/2024] [Indexed: 04/12/2024]
Abstract
AIM This study aims to design chemically crosslinked thiolated cyclodextrin-based hydrogels and to evaluate their mucoadhesive properties via mucosal residence time studies on porcine small intestinal mucosa and on porcine buccal mucosa. METHODS Free thiol groups of heptakis(6-deoxy-6-thio)-β-cyclodextrin (β-CD-SH) were S-protected with 2-mercaptoethanesulfonic acid (MESNA) followed by crosslinking with citric acid. Cytotoxicity was assessed by hemolysis as well as resazurin assay. Hydrogels were characterized by their rheological and mucoadhesive properties. Ritonavir was employed as model drug for in vitro release studies from these hydrogels. RESULTS The structure of S-protected β-CD-SH was confirmed by IR and 1H NMR spectroscopy. Degree of thiolation was 390 ± 7 µmol/g. Hydrogels based on native β-CD showed hemolysis of 12.5 ± 2.5 % and 13.6 ± 2.7 % within 1 and 3 h, whereas hemolysis of just 3.5 ± 2.8 % and 3.9 ± 3.0 % was observed for the S-protected thiolated CD hydrogels, respectively. Both native and S-protected thiolated hydrogels showed minor cytotoxicity on Caco-2 cells. Rheological investigations of S-protected thiolated β-CD-based hydrogel (16.2 % m/v) showed an up to 13-fold increase in viscosity in contrast to the corresponding native β-CD-based hydrogel. Mucosal residence time studies showed that thiolated β-CD-based hydrogel is removed to a 16.6- and 2.4-fold lower extent from porcine small intestinal mucosa and porcine buccal mucosa in comparision to the native β-CD-based hydrogel, respectively. Furthermore, a sustained release of ritonavir from S-protected thiolated β-CD-based hydrogels was observed. CONCLUSION Because of their comparatively high mucoadhesive and release-controlling properties, S-protected thiolated β-CD-based hydrogels might be promising systems for mucosal drug delivery.
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Affiliation(s)
- Andrea Fürst
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Gergely Kali
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Aida Dizdarević
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Daniel Stengel
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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Veider F, Haddadzadegan S, Sanchez Armengol E, Laffleur F, Kali G, Bernkop-Schnürch A. Inhibition of P-glycoprotein-mediated efflux by thiolated cyclodextrins. Carbohydr Polym 2024; 327:121648. [PMID: 38171673 DOI: 10.1016/j.carbpol.2023.121648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/20/2023] [Accepted: 11/26/2023] [Indexed: 01/05/2024]
Abstract
Overcoming P-glycoprotein (P-gp)-mediated efflux poses a significant challenge for the pharmaceutical industry. This study investigates the potential of thiolated β-cyclodextrins (β-CD-SHs) as inhibitors of P-gp-mediated efflux in Caco-2 cells. Through a series of transport assays, intracellular accumulation, and efflux of the P-gp substrates Rhodamine 123 (Rh123) and Calcein-AM with and without co-administration of β-CD-SHs were assessed. The results revealed that the cellular uptake of Rh123 and Calcein-AM were enhanced up to 7- and 3-fold, compared to the control, respectively. In efflux studies an up to 2.5-fold reduction of the Rh123 efflux was reached compared the control, indicating a substantial decrease of Rh123 efflux by β-CD-SHs. Furthermore, it was observed that β-CD-SHs led to a decrease in the reactivity of fluorescence-labeled anti-P-gp, suggesting additional effects on the conformation of P-gp. Overall, this study demonstrates the potential of β-CD-SHs as effective modulator of P-gp-mediated drug efflux in Caco-2 cells.
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Affiliation(s)
- Florina Veider
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Soheil Haddadzadegan
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Eva Sanchez Armengol
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Flavia Laffleur
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Gergely Kali
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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Kali G, Haddadzadegan S, Bernkop-Schnürch A. Cyclodextrins and derivatives in drug delivery: New developments, relevant clinical trials, and advanced products. Carbohydr Polym 2024; 324:121500. [PMID: 37985088 DOI: 10.1016/j.carbpol.2023.121500] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 09/21/2023] [Accepted: 10/13/2023] [Indexed: 11/22/2023]
Abstract
Cyclodextrins (CD) and derivatives are functional excipients that can improve the bioavailability of numerous drugs. Because of their drug solubility improving properties they are used in many pharmaceutical products. Furthermore, the stability of small molecular drugs can be improved by the incorporation in CDs and an unpleasant taste and smell can be masked. In addition to well-established CD derivatives including hydroxypropyl-β-CD, hydroxypropyl-γ-CD, methylated- β-CD and sulfobutylated- β-CD, there are promising new derivatives in development. In particular, CD-based polyrotaxanes exhibiting cellular uptake enhancing properties, CD-polymer conjugates providing sustained drug release, enhanced cellular uptake, and mucoadhesive properties, and thiolated CDs showing mucoadhesive, in situ gelling, as well as permeation and cellular uptake enhancing properties will likely result in innovative new drug delivery systems. Relevant clinical trials showed various new applications of CDs such as the formation of CD-based nanoparticles, stabilizing properties for protein drugs or the development of ready-to-use injection systems. Advanced products are making use of various benefical properties of CDs at the same time. Within this review we provide an overview on these recent developments and take an outlook on how this class of excipients will further shape the landscape of drug delivery.
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Affiliation(s)
- Gergely Kali
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria
| | - Soheil Haddadzadegan
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria
| | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria.
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Fürst A, Kali G, Efiana NA, Akkuş-Dağdeviren ZB, Haddadzadegan S, Bernkop-Schnürch A. Thiolated cyclodextrins: A comparative study of their mucoadhesive properties. Int J Pharm 2023; 635:122719. [PMID: 36791998 DOI: 10.1016/j.ijpharm.2023.122719] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023]
Abstract
AIM The aim of this study was the comparison of the mucoadhesive properties of nonionic, negatively, and positively charged thiolated cyclodextrins (CDs), including α-, β-, and γ-CDs of low and high degree of thiolation. METHODS Native α-, β-, and γ-CDs were thiolated with phosphorous pentasulfide in sulfolane (CD-SH) (i), via reductive amination with cysteamine after oxidative ring opening (CD-Cya) (ii), and via esterification with mercaptosuccinic acid (CD-MSA) (iii). These thiolated CDs were characterized via 1H NMR and Ellman's test. Cytotoxicity was determined via resazurin and hemolysis assay. Mucoadhesive properties were evaluated via rheological studies with freshly isolated porcine mucus, as well as residence time studies on porcine small intestinal mucosa. RESULTS The structure of thiolated CDs was confirmed via 1H NMR. The degree of thiolation was in the range of 594-1034 µmol/g for low and 1360-3379 µmol/g for high CD-SH, whereas thiolated CD-Cya and thiolated CD-MSA exhibited a degree of thiolation of 1142-3242 µmol/g and 243-1227 µmol/g, respectively. Just cationic CDs showed cytotoxicity. Nonionic highly thiolated α-CD-SH, α-CD-Cya, and α-CD-MSA exhibited with mucus 5.6-, 15.7- and 2.8-fold improved dynamic viscosity, while improvement was 7.7-, 6.1-, and 5.4-fold for the corresponding thiolated β-CDs and 12.3-, 15.4- and 17.8-fold for the corresponding thiolated γ-CDs compared with native CDs, respectively. A prolonged mucosal residence time following the rank order γ > β > α was observed for all thiolated CDs, whereby γ-CD-Cya, nonionic highly thiolated β-CD-SH and α-CD-Cya showed the highest mucoadhesive properties. CONCLUSION A high degree of thiolation and the introduction of cationic charges are mainly responsible for high mucoadhesive properties of CDs.
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Affiliation(s)
- Andrea Fürst
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Gergely Kali
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Nuri Ari Efiana
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Zeynep Burcu Akkuş-Dağdeviren
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Soheil Haddadzadegan
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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Fürst A, Shahzadi I, Burcu Akkuş-Dağdeviren Z, Kali G, Hupfauf A, Gust R, Bernkop-Schnürch A. Entirely S-protected thiolated hydroxyethylcellulose: Design of a dual cross-linking approach for hydrogels. Eur J Pharm Biopharm 2022; 181:292-9. [PMID: 36427674 DOI: 10.1016/j.ejpb.2022.11.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 11/17/2022] [Accepted: 11/18/2022] [Indexed: 11/25/2022]
Abstract
AIM The aim of this study was the synthesis and evaluation of entirely S-protected thiolated hydroxyethylcellulose (HEC) with low and high viscosity, as well as thiolated poly-L-lysine (poly-L-Lys) used as dual-acting ionic as well as thiol-disulfide exchange mediated cross-linking hydrogel. METHODS Bis(mercaptosuccinic acid) was covalently attached to low and high viscous HECs via Fisher esterification, obtaining S-protected polymers. Poly-L-Lys-cysteine was synthesized via amidation of poly-L-Lys-HBr with cysteine (Cys). Thiolated polymers were examined in terms of cytotoxicity and rheological behavior of hydrogels containing these thiomers was evaluated with a cone-plate rheometer. RESULTS Thiomers showed less cytotoxicity compared to the corresponding unmodified polymers. Rheological studies showed that cross-linking occurred between the two polymers via thiol-disulfide exchange reactions facilitated by the complementary charges. Employing poly-L-Lys-Cys in a concentration of either 0.5 or 5% (m/v) resulted in a 34.5-fold or 17.3-fold as well as a 53.6-fold or 29.6-fold improvement in dynamic viscosity within 5 min at 37 °C on S-protected thiolated low and high viscous HEC, compared to the corresponding unmodified HECs, respectively. CONCLUSION By the combination of anionic S-protected thiolated polymers with a cationic thiolated polymer, dual-acting hydrogels exhibiting a time dependent increase in viscosity can be designed.
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Francesco Racaniello G, Knoll P, Matteo Jörgensen A, Arduino I, Laquintana V, Assunta Lopedota A, Bernkop-Schnürch A, Denora N. Thiolation of non-ionic surfactants for the development of lipid-based mucoadhesive drug delivery systems. Eur J Pharm Biopharm 2022; 179:95-104. [PMID: 36058444 DOI: 10.1016/j.ejpb.2022.08.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 08/19/2022] [Accepted: 08/27/2022] [Indexed: 11/28/2022]
Abstract
The aim of this study was to develop thiolated self-emulsifying drug delivery systems (SEDDS) and nanostructured lipid carriers (NLCs) with improved mucoadhesive properties. Two non-ionic surfactants bearing a short and long PEG chain, namely polyoxyethylene (10) stearyl ether (PSE10) and polyoxyethylene (100) stearyl ether (PSE100), were thiolated for the first time by substituting the terminal hydroxyl group with a thiol group. The synthesis was confirmed by FT-IR, NMR and Ellman's test. SEDDS and NLCs containing these thiolated compounds were investigated for size, polydispersity index (PDI) and ζ potential. Subsequently, mucus diffusion studies, rheological evaluations after mixing the nanocarriers with mucus and mucoadhesion studies on porcine intestinal mucosa were performed. All nanocarriers had a size less than 250 nm, a maximum PDI of 0.3 and a ζ potential < -9.0 mV. Mucus diffusion studies resulted in the rank order of increasing diffusivity: PSE10-SH < PSE100-SH < PSE10-OH < PSE100-OH for NLCs and PSE10-OH < PSE100-OH < PSE100-SH < PSE10-SH for SEDDS. The mucoadhesive properties and increase in viscosity of SEDDS and NLCs ranked: PSE100-OH < PSE10-OH < PSE100-SH < PSE10-SH. In addition, the short chain PSE10-SH showed higher mucus interactions than the long chain PSE100-SH for both SEDDS and NLCs. The thiolated PSE surfactants appeared to be promising excipients for the design of highly mucoadhesive drug delivery systems.
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Affiliation(s)
| | - Patrick Knoll
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Austria
| | - Arne Matteo Jörgensen
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Austria
| | - Ilaria Arduino
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", Italy
| | - Valentino Laquintana
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", Italy
| | | | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Austria
| | - Nunzio Denora
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", Italy.
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Medeiros Borsagli FGL, Rodrigues JS, Aguiar RA, Paiva AE, Vasquez JFB, Ramos WTDS, Allibrandini P, Rocha EPA, Gonçalves MP, de Souza FE. Low-cost luminescent scaffolds-based on thiol chitosans by microwave radiation for vertebral disc repair/theragnostic. Int J Biol Macromol 2022; 209:2109-2118. [PMID: 35513089 DOI: 10.1016/j.ijbiomac.2022.04.191] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2022] [Revised: 04/19/2022] [Accepted: 04/25/2022] [Indexed: 12/18/2022]
Abstract
This study introduces a new 3D scaffold based on thiolated chitosans with luminescence by microwave radiation using cysteine (Chi_CT_Cys) and 11-mercaptoundecanoic acid (Chi_CT_MUA) for vertebral disc regeneration/theragnostic. These scaffolds were characterized by Raman, PL spectroscopy, swelling, gel-fraction, and morphologies. Cytocompatibility and mechanical behavior were evaluated. Raman showed that disulfide bonds improved the grafting degree (Chi_CT_Cys (1072 ± 136) μmol·g-1 and Chi_CT_MUA (3245 ± 105) μmol·g-1). Morphologies showed interesting characteristics. Swelling behavior showed that Chi_CT_MUA presented a slight minor swelling (2101 ± 251) % compared to Chi_CT_Cys (2589 ± 188) %. Differently, gel-fraction showed that the chemical stability of Chi_CT_Cys was worse (29 ± 4) % than Chi_CT_MUA (15 ± 3) %. PL showed a possibility to use theragnostic evaluation of points of greater compression in a vertebral disc. The mechanical behavior of Chi_CT_MUA presented better results ((70 ± 3) MPa) than Chi_CT_Cys ((37 ± 3) MPa). Cytocompatible showed that the scaffolds presented cell viability >90%. Thusly, these 3D scaffolds presented an incredible potential for tissue engineering applications.
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Affiliation(s)
- Fernanda G L Medeiros Borsagli
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil.
| | - Jordane S Rodrigues
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | - Rafaella A Aguiar
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | | | | | - Welyson Tiano do Santos Ramos
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | - Paulo Allibrandini
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | - Elém Patrícia Alves Rocha
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | - Max P Gonçalves
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
| | - Fidel Edson de Souza
- Institute of Engineering, Science and Technology, Universidade Federal dos Vales do Jequitinhonha e Mucuri/UFVJM, Av. 01, 4050 Cidade Universitária, 39440-039, Janaúba, MG, Brazil
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Racaniello GF, Laquintana V, Summonte S, Lopedota A, Cutrignelli A, Lopalco A, Franco M, Bernkop-Schnürch A, Denora N. Spray-dried mucoadhesive microparticles based on S-protected thiolated hydroxypropyl-β-cyclodextrin for budesonide nasal delivery. Int J Pharm 2021; 603:120728. [PMID: 34029665 DOI: 10.1016/j.ijpharm.2021.120728] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2021] [Revised: 05/18/2021] [Accepted: 05/19/2021] [Indexed: 12/27/2022]
Abstract
Budesonide (BUD) is used as first choice therapy for the treatment of allergic rhinitis, a chronic allergic-immune condition with an increased incidence in the pediatric population. The main problem of BUD nasal formulations is related to its poor aqueous solubility (S0 = 5.03·10-5 M), sometimes compensated by the administration of high doses of the drug. The ability of thiolated hydroxypropyl-β-cyclodextrin (HP- β -CD-SH, 100 mM) to increase the water solubility of BUD (SHP- β-CD-SH = 10.9·10-3 M) more than pristine hydroxypropyl- β -cyclodextrin (HP- β-CD, SHP- β-CD = 4.3·10-3 M) has been previously demonstrated. Considering that S-protected thiomers have the advantage of increasing the stability of thiols over a wide pH range prolonging their residence time at the target site, 2-mercapto-nicotinic acid (MNA) was used in this study to protect the free thiol groups on HP- β -CD-SH generating the corresponding S-protected cyclodextrin (HP-β-CD-MNA). Besides, given the increased stability and processability of HP-β-CD-MNA, mucoadhesive microparticles (MPs) were prepared via spray-drying of aqueous solutions of the inclusion complex HP-β-CD-MNA/BUD. MPs were morphologically and dimensionally homogeneous exhibiting an average diameter of 3.24 ± 0.57 µm. Over time these MPs formed larger aggregates with an average diameter of 10-50 μm, suitable for the design of intranasal delivery systems. Differential scanning calorimetry analyses revealed the absence of crystalline BUD from spray-dried complexes. Dissolution studies shown that spray-dried MPs dissolved quickly and the complexed drug was completely solubilized within the first 20 min of the dissolution process. Cell viability assay indicated that spray-dried complexes are safe. In vitro mucoadhesion studies on freshly excised porcine nasal mucosa showed a 1.4- and 2.3-fold prolonged mucosal residence time of HP- β -CD-SH/BUD and HP-β-CD-MNA/BUD in comparison to the unmodified cyclodextrin (CD), respectively. Rheological behaviour of spray-dried MPs complexes/mucus mixtures confirmed the results of the mucoadhesion studies, as the dynamic viscosity of the spray-dried inclusion complexes HP-β-CD-SH/BUD and HP-β-CD-MNA/BUD was 1.1-fold and 2.4 fold increased in comparison to the unmodified HP-β-CD/BUD complex. According to these results, MPs comprising HP- β -CD-MNA/BUD might be a promising tool for nasal delivery of poorly water-soluble corticosteroids such as BUD.
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Affiliation(s)
| | - Valentino Laquintana
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Simona Summonte
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy; Thiomatrix Forschungs- und Beratungs GmbH, Research Center Innsbruck, Trientlgasse 65, 6020 Innsbruck, Austria
| | - Angela Lopedota
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Annalisa Cutrignelli
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Antonio Lopalco
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Massimo Franco
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy
| | - Andreas Bernkop-Schnürch
- Thiomatrix Forschungs- und Beratungs GmbH, Research Center Innsbruck, Trientlgasse 65, 6020 Innsbruck, Austria; Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Nunzio Denora
- Department of Pharmacy - Pharmaceutical Sciences, University of Bari "Aldo Moro", 70125 Bari, Italy.
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Harrer D, Sanchez Armengol E, Friedl JD, Jalil A, Jelkmann M, Leichner C, Laffleur F. Is hyaluronic acid the perfect excipient for the pharmaceutical need? Int J Pharm 2021; 601:120589. [PMID: 33845151 DOI: 10.1016/j.ijpharm.2021.120589] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 03/31/2021] [Accepted: 04/05/2021] [Indexed: 02/08/2023]
Abstract
Hyaluronic acid has become an interesting and important polymer as an excipient for pharmaceutical products due to its beneficial properties, like solubility, biocompatibility and biodegradation. To improve the properties of hyaluronic acid, different possibilities for chemical modifications are presented, and the opportunities as novel systems for drug delivery are discussed. This review gives an overview over the production of hyaluronic acid, the possibilities of its chemical modification and the current state of in vitro and in vivo research. Furthermore, market approved and commercially available products are reviewed and derivatives undergoing clinical trials and applying for market approval are shown. In particular, hyaluronic acid has been studied for different administrations in rheumatology, ophthalmology, local anesthetics, cancer treatment and bioengineering of tissues. The present work concludes with perspectives for future administration of pharmaceuticals based on hyaluronic acid.
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Affiliation(s)
- Daniela Harrer
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Eva Sanchez Armengol
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Julian D Friedl
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Aamir Jalil
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Max Jelkmann
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Christina Leichner
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Flavia Laffleur
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria.
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Medeiros Borsagli FGL, de Souza AJM, Paiva AE. Ecofriendly multifunctional thiolated carboxymethyl chitosan-based 3D scaffolds with luminescent properties for skin repair and theragnostic of tissue regeneration. Int J Biol Macromol 2020; 165:3051-64. [PMID: 33127543 DOI: 10.1016/j.ijbiomac.2020.10.186] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 10/22/2020] [Accepted: 10/23/2020] [Indexed: 01/12/2023]
Abstract
Luminescent biopolymers, namely carboxymethyl chitosan, have become a target of attention due to their potential for biomedical applications. In this context, biomaterials capable of improving theragnostic tissue regeneration and provide a tissue repair remain a challenge. This study introduces a new 3D scaffold based on two innovative thiolated carboxymethyl chitosan with cysteine (CMCCys) and 11-mercaptoundecanoic acid (CMCMerc) resulting in enhanced fluorescence of CMC for repair and theragnostic of tissue regeneration. Those thiolated CMCs were intensively characterized by spectroscopy techniques (FTIR, NMR), swelling degree, chemical stability (Gel-fraction, GF) and morphological analysis (SEM, microtomography, BET). In addition, the photoluminescence properties were evaluated and cytocompatibility was performed via in vitro bioassays. The results demonstrated that those scaffolds presented interconnected 3D porous (porosity > 80%), a great GF, and a high degree of thiolation (2%-11%). Furthermore, the spectroscopy analysis elucidated a significant disulfide bond formation, which guaranteed mechanical stability for applications in tissue engineering (elastic modulus, (22 ± 3) kPa and (35 ± 2) kPa, for CMCCys and CMCMerc, respectively). Additionally, the incorporation of thiol group improved the fluorescence of CMC and they presented cytocompatibility > 90%. Thus, for the first time, a multifunctional 3D CMC thiomer was produced for applications in repair and theragnostic of tissue regeneration.
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11
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Netsomboon K, Jalil A, Laffleur F, Hupfauf A, Gust R, Bernkop-Schnürch A. Thiolated chitosans: Are Cys-Cys ligands key to the next generation? Carbohydr Polym 2020; 242:116395. [PMID: 32564864 DOI: 10.1016/j.carbpol.2020.116395] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2020] [Revised: 04/22/2020] [Accepted: 04/28/2020] [Indexed: 12/22/2022]
Abstract
The potential of Cys-Cys ligands for the development of a novel type of S-protected thiomers was evaluated. S-protected thiomers chitosan-N-acetylcysteine-mercaptonicotinamide (CS-NAC-MNA) and chitosan-N-acetylcysteine-N-acetylcysteine (CS-NAC-NAC) were synthesized and characterized. Viscosity of polymers in presence of various concentrations of S-amino acids was monitored. Mucoadhesive properties were evaluated. FT-IR characterization confirmed the covalent attachment of NAC-MNA and NAC-NAC. Attached sulfhydryl groups were found in the range of 550 μmol/g. In the presence of amino acids bearing a free thiol group viscosity of both polymers increased. This increase in viscosity depended on the amount of added free thiols. Maximum force required to detach CS-NAC-MNA and CS-NAC-NAC from porcine intestinal mucosa was 1.4- and 2.7-fold higher than that required for chitosan, respectively. CS-NAC-MNA adhered up to 3 h, whereas CS-NAC-NAC adhered even for 8 h on this mucosa. Accordingly, the Cys-Cys substructure could be identified as highly potent ligand for the design of mucoadhesive polymers.
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Affiliation(s)
- Kesinee Netsomboon
- Division of Pharmaceutical Sciences, Faculty of Pharmacy, Thammasat University (Rangsit Campus), Khlong Luang, Pathumthani 12120, Thailand
| | - Aamir Jalil
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria
| | - Flavia Laffleur
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria
| | - Andrea Hupfauf
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Ronald Gust
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck 6020, Austria.
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12
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Leichner C, Jelkmann M, Bernkop-Schnürch A. Thiolated polymers: Bioinspired polymers utilizing one of the most important bridging structures in nature. Adv Drug Deliv Rev 2019; 151-152:191-221. [PMID: 31028759 DOI: 10.1016/j.addr.2019.04.007] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2019] [Revised: 04/16/2019] [Accepted: 04/16/2019] [Indexed: 12/13/2022]
Abstract
Thiolated polymers designated "thiomers" are obtained by covalent attachment of thiol functionalities on the polymeric backbone of polymers. In 1998 these polymers were first described as mucoadhesive and in situ gelling compounds forming disulfide bonds with cysteine-rich substructures of mucus glycoproteins and crosslinking through inter- and intrachain disulfide bond formation. In the following, it was shown that thiomers are able to form disulfides with keratins and membrane-associated proteins exhibiting also cysteine-rich substructures. Furthermore, permeation enhancing, enzyme inhibiting and efflux pump inhibiting properties were demonstrated. Because of these capabilities thiomers are promising tools for drug delivery guaranteeing a strongly prolonged residence time as well as sustained release on mucosal membranes. Apart from that, thiomers are used as drugs per se. In particular, for treatment of dry eye syndrome various thiolated polymers are in development and a first product has already reached the market. Within this review an overview about the thiomer-technology and its potential for different applications is provided discussing especially the outcome of studies in non-rodent animal models and that of numerous clinical trials. Moreover, an overview on product developments is given.
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13
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Jalil A, Asim MH, Le NMN, Laffleur F, Matuszczak B, Tribus M, Bernkop-Schnürch A. S-protected gellan gum: Decisive approach towards mucoadhesive antimicrobial vaginal films. Int J Biol Macromol 2019; 130:148-157. [PMID: 30779984 DOI: 10.1016/j.ijbiomac.2019.02.092] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2018] [Revised: 02/08/2019] [Accepted: 02/15/2019] [Indexed: 01/09/2023]
Abstract
The aim of this study was to synthesize novel polymeric excipients forming mucoadhesive films for treatment of vaginal microbial infections. 2-(2-Amino ethyldisulfanyl) nicotinic acid was conjugated with gellan gum via amide bond formation. The structure of the resulting S-protected gellan gum was confirmed by 1H NMR. S-protected gellan gum variants were characterized for thiol content, cytotoxicity, rheological behaviour and film forming capability. Depending on the added amount of AMENA degree of thiolation was 81 ± 13 (S-GG 81) and 174 ± 16 (S-GG 174) μmol/g, respectively. Vaginal films were casted from S-protected gellan gum variants and studied for adherence to vaginal mucosa, drug release and antimicrobial activity. S-protected gellan gum remained biocompatible showing >87% cell viability. S-GG 81 and S-GG 174 exhibited 1.84- and 4.3-fold increased dynamic viscosity in porcine mucus in comparison to unmodified gellan gum, respectively. Compared to gellan gum films, thiol functionalized gellan gum films showed 3-fold improved adhesion on mucosal surface over a period of 3 h along with significant antimicrobial activity. Moreover, S-protected gellan gum provided a sustained release of metronidazole. According to these results, S-protected gellan gum proved to be a promising novel excipient for casting vaginal films, exhibiting strongly improved mucoadhesive and antimicrobial properties.
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Affiliation(s)
- Aamir Jalil
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Mulazim Hussain Asim
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria; Department of Pharmaceutics, Faculty of Pharmacy, University of Sargodha, 40100 Sargodha, Pakistan
| | - Nguyet-Minh Nguyen Le
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria; Department of Industrial Pharmacy, University of Medicine and Pharmacy, 70000 Ho Chi Minh City, Viet Nam
| | - Flavia Laffleur
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Barbara Matuszczak
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Chemistry, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Martina Tribus
- Institute of Mineralogy and Petrography, Innrain 52, University of Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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14
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Zhang Y, Zhou S, Deng F, Chen X, Wang X, Wang Y, Zhang H, Dai W, He B, Zhang Q, Wang X. The function and mechanism of preactivated thiomers in triggering epithelial tight junctions opening. Eur J Pharm Biopharm 2018; 133:188-199. [PMID: 30359716 DOI: 10.1016/j.ejpb.2018.10.014] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Revised: 10/18/2018] [Accepted: 10/20/2018] [Indexed: 12/17/2022]
Abstract
As a unique macromolecular permeation enhancer, thiolated polymers (thiomers), especially the preactivated thiomers, have demonstrated great merits in oral delivery of protein/peptide drugs by triggering epithelial tight junctions (TJs) opening. However, the underlying molecular mechanism remains unclear. To clarify this issue, preactivated thiomers were synthesized and their TJs opening function as well as signaling pathways on MDCK and Caco-2 cell monolayers was investigated. The results showed that preactivated thiomers could reduce TEER and increase the permeation of Na-Flu and FITC-Insulin over 2-fold and 4-fold on MDCK monolayers, respectively, indicating their huge potential as macromolecular permeation enhancers. The signaling pathway study showed that intracellular PTK Src but not FAK, involved in the TJs opening by claudin-4 disruption. Src activation was based on interaction between thiol group of thiomers and cysteine-riched Src upstream membrane receptors, EGFR and IGFR. The deep comprehension of the thiomers-mediated TJs opening mechanisms provides goodness in application of protein/peptide drugs for the oral delivery.
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Affiliation(s)
- Yang Zhang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Shurong Zhou
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Feiyang Deng
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xianhui Chen
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Xing Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Yaoqi Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Hua Zhang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Wenbing Dai
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Bing He
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China
| | - Qiang Zhang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China; The State Key Laboratory of Natural and Biomimetic Drugs, Peking University, Beijing 100191, China
| | - Xueqing Wang
- Beijing Key Laboratory of Molecular Pharmaceutics and New Drug Delivery Systems, School of Pharmaceutical Sciences, Peking University, Beijing 100191, China.
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Perrone M, Lopalco A, Lopedota A, Cutrignelli A, Laquintana V, Franco M, Bernkop-Schnürch A, Denora N. S-preactivated thiolated glycol chitosan useful to combine mucoadhesion and drug delivery. Eur J Pharm Biopharm 2018; 132:103-111. [PMID: 30253185 DOI: 10.1016/j.ejpb.2018.09.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 09/21/2018] [Accepted: 09/21/2018] [Indexed: 11/15/2022]
Abstract
This work describes S-preactivated N-acetylcysteine (NAC)- and glutathione (GSH)-glycol chitosan (GC) polymer conjugates engineered as potential mucoadhesive platform. Preactivated thiomers (GC-NAC-MNA, GC-GSH-MNA) were synthesized by bond formation between GC-NAC or GC-GSH and 2-mercaptonicotinic acid (MNA) used as ligand. The presence of protected thiol moieties on this new class of thiolated GC made them not subject to oxidation. The structural modifications of the resulting derivatives were confirmed by proton Nuclear Magnetic Resonance (1H NMR) and Size Exclusion Chromatography (SEC). The conjugates displayed 91.2% and 90.1% of S-preactivation for GC-NAC-MNA and GC-GSH-MNA, respectively. The polymers were tested in ex-vivo and in vitro for their mucoadhesive properties and toxicity. The results showed that the preactivation of GC-NAC and GC-GSH increased their mucoadhesive abilities compared to their thiolated precursors by 1.4-, 4.4-fold in time of adhesion evaluated using rotating cylinder method, 1.6-, 1.5-fold in total work of adhesion (TWA) and 2.0-, 1.3-fold in maximum detachment force (MDA) determined using tensile studies, respectively. Moreover, water-uptake studies showed an improved in weight indicating water-uptake strongly dependent on derivations, before erosion occurred, whereas disintegration took place for the thiolated polymers within the first hour. The S-preactivated modification did not affect the cell viability of Caco2 cells exposed to the polymers. The release of the model drug sodium naproxen from tablets prepared with a lyophilized mixture of drug and polymer was studied via dissolution apparatus revealing that the preactivation on GC-GSH and GC-NAC involves a slowdown in the drug release rate. The results shown that the novel preactivated thiolated GC-derivatives can be considered promising excipients for the development of mucoadhesive drug delivery systems.
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Affiliation(s)
- Mara Perrone
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy; Istituto Tumori IRCCS "Giovanni Paolo II", Bari, Italy
| | - Antonio Lopalco
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Angela Lopedota
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Annalisa Cutrignelli
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Valentino Laquintana
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Massimo Franco
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, Leopold-Franzens-University of Innsbruck, Innsbruck, Austria
| | - Nunzio Denora
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy.
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16
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Perrone M, Lopalco A, Lopedota A, Cutrignelli A, Laquintana V, Douglas J, Franco M, Liberati E, Russo V, Tongiani S, Denora N, Bernkop-Schnürch A. Preactivated thiolated glycogen as mucoadhesive polymer for drug delivery. Eur J Pharm Biopharm 2017; 119:161-169. [PMID: 28610879 DOI: 10.1016/j.ejpb.2017.06.011] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2017] [Revised: 05/31/2017] [Accepted: 06/09/2017] [Indexed: 11/30/2022]
Abstract
The purpose of this study was to synthesize and characterize a novel thiolated glycogen, so-named S-preactivated thiolated glycogen, as a mucosal drug delivery systems and the assessment of its mucoadhesive properties. In this regard, glycogen-cysteine and glycogen-cysteine-2-mercaptonicotinic acid conjugates were synthesized. Glycogen was activated by an oxidative ring opening with sodium periodate resulting in reactive aldehyde groups to which cysteine was bound via reductive amination. The obtained thiolated polymer displayed 2203.09±200μmol thiol groups per gram polymer. In a second step, the thiol moieties of thiolated glycogen were protected by disulfide bond formation with the thiolated aromatic residue 2-mercaptonicotinic acid (2MNA). In vitro screening of mucoadhesive properties was performed on porcine intestinal mucosa using different methods. In particular, in terms of rheology investigations of mucus/polymer mixtures, the S-preactivated thiolated glycogen showed a 4.7-fold increase in dynamic viscosity over a time period of 5h, in comparison to mucus/Simulated Intestinal Fluid control. The S-preactivated polymer remained attached on freshly excised porcine mucosa for 45h. Analogous results were obtained with tensile studies demonstrating a 2.7-fold increase in maximum detachment force and 3.1- fold increase in total work of adhesion for the S-preactivated polymer compared to unmodified glycogen. Moreover, water-uptake studies showed an over 4h continuing weight gain for the S-preactivated polymer, whereas disintegration took place for the unmodified polymer within the first hour. Furthermore, even in the highest tested concentration of 2mg/ml the new conjugates did not show any cytotoxicity on Caco-2 cell monolayer using an MTT assay. According to these results, S-preactivated glycogen represents a promising type of mucoadhesive polymers useful for the development of various mucosal drug delivery systems.
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Affiliation(s)
- Mara Perrone
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy; Department of Pharmaceutical Technology, Institute of Pharmacy, Leopold-Franzens-University of Innsbruck, Innsbruck, Austria
| | - Antonio Lopalco
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Angela Lopedota
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Annalisa Cutrignelli
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Valentino Laquintana
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | - Justin Douglas
- Nuclear Magnetic Resonance Core Laboratory, University of Kansas, Lawrence, KS 66045, USA
| | - Massimo Franco
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy
| | | | | | | | - Nunzio Denora
- Department of Pharmacy - Drug Sciences, University of Bari "Aldo Moro", Bari, Italy.
| | - Andreas Bernkop-Schnürch
- Department of Pharmaceutical Technology, Institute of Pharmacy, Leopold-Franzens-University of Innsbruck, Innsbruck, Austria.
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17
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Palazzo C, Trapani G, Ponchel G, Trapani A, Vauthier C. Mucoadhesive properties of low molecular weight chitosan- or glycol chitosan- and corresponding thiomer-coated poly(isobutylcyanoacrylate) core-shell nanoparticles. Eur J Pharm Biopharm 2017; 117:315-23. [PMID: 28455206 DOI: 10.1016/j.ejpb.2017.04.020] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2016] [Revised: 04/05/2017] [Accepted: 04/20/2017] [Indexed: 01/28/2023]
Abstract
The aim of the present work was to evaluate the mucoadhesive properties of poly(isobutyl cyanoacrylate) (PIBCA) nanoparticles (NPs) coated with Low Molecular Weight (LMW) chitosan (CS)- and glycol chitosan (GCS)-based thiomers as well as with the corresponding LMW unmodified polysaccharides. For this purpose, all the CS- and GCS-based thiomers were prepared under simple and mild conditions starting from the LMW unmodified polymers CS and GCS. The resulting NPs were of spherical shape with diameters ranging from 400 to 600nm and 187 to 309nm, for CS- and GCS-based NPs, respectively. The mucoadhesive characteristics of these core shell NPs were studied in Ussing chambers measuring the percentage of NPs stuck on the mucosal of fresh intestinal tissue after 2h of incubation. Moreover, incubation of nanoparticle formulations with the intestinal tissue induced changes in transmucosal electrical resistance which were measured to gain information into the opening of tight junctions and to control the integrity of the mucosa. Thus, it was found that PIBCA NPs coated with the GCS-Glutathione conjugate (GCGPIBCA NPs) possessed the most favorable mucoadhesive performances. Moreover, both GCGPIBCA- and GCS-N-acetyl-cysteine (GCNPIBCA)-core-shell NPs might induced an enlargement of the epithelial cell tight junctions. In conclusion, coating of PIBCA NPs with GCS-based thiomers may be useful for improving the mucoadhesive and permeation properties of these nanocarriers.
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18
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Mun EA, Williams AC, Khutoryanskiy VV. Adhesion of thiolated silica nanoparticles to urinary bladder mucosa: Effects of PEGylation, thiol content and particle size. Int J Pharm 2016; 512:32-38. [PMID: 27530813 DOI: 10.1016/j.ijpharm.2016.08.026] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 08/10/2016] [Accepted: 08/13/2016] [Indexed: 12/15/2022]
Abstract
Intravesical drug administration is used to deliver cytotoxic agents through a catheter to treat bladder cancer. One major limitation of this approach is poor retention of the drug in the bladder due to periodic urine voiding. Mucoadhesive dosage forms thus offer significant potential to improve drug retention in the bladder. Here, we investigate thiolated silica nanoparticles retention on porcine bladder mucosa in vitro, quantified through Wash Out50 (WO50) values, defined as the volume of liquid necessary to remove 50% of the adhered particles from a mucosal tissue. Following irrigation with artificial urine solution, the thiolated nanoparticles demonstrate significantly greater retention (WO50 up to 36mL) compared to non-mucoadhesive dextran (WO50 7mL), but have weaker mucoadhesive properties than chitosan (WO50 89mL). PEGylation of thiolated silica reduces their mucoadhesion with WO50 values of 29 and 8mL for particles decorated with 750 and 5000Da PEG, respectively. The retention of thiolated silica nanoparticles is dependent on their thiol group contents and physical dimensions.
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Affiliation(s)
- Ellina A Mun
- Reading School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AD, United Kingdom
| | - Adrian C Williams
- Reading School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AD, United Kingdom
| | - Vitaliy V Khutoryanskiy
- Reading School of Pharmacy, University of Reading, Whiteknights, Reading, RG6 6AD, United Kingdom.
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19
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Menzel C, Silbernagl J, Laffleur F, Leichner C, Jelkmann M, Huck CW, Hussain S, Bernkop-Schnürch A. 2,2'Dithiodinicotinyl ligands: Key to more reactive thiomers. Int J Pharm 2016; 503:199-206. [PMID: 26972378 DOI: 10.1016/j.ijpharm.2016.03.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2016] [Revised: 02/29/2016] [Accepted: 03/09/2016] [Indexed: 01/10/2023]
Abstract
The aim of this study was to establish a novel type of preactivated thiomers exhibiting a comparatively higher reactivity with mucus and consequently improved mucoadhesive properties. In order to achieve this goal, the dimeric form of 2-mercaptonicotinic acid (MNA-MNA) was directly attached to the polymeric backbone of chitosan (CHI) via amide bond formation mediated by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDAC) used as a coupling reagent. The remaining free amino groups were in the following reacted with succinic anhydride (Succ) in order to obtain a uniformly anionically charged polymer (CHI-Succ-MNA-MNA). Within this study, different coupling rates of up to 170 μmol MNA-MNA per gram polymer were achieved. The attachment of the dimeric ligand resulted in a preactivated thiomer with a comparatively more reactive disulfide substructure due to the additional nitrogen atom in conjugation over the aromatic moieties. Furthermore, the obtained polymer is entirely preactivated and thus prevented against undesired oxidation reactions. Kinetic studies of disulfide exchange reactions showed a 3.8-fold higher reactivity of CHI-Succ-MNA-MNA in comparison to a state-of-the-art preactivated thiomer. Within rheological measurements, CHI-Succ-MNA-MNA with a coupling rate of 170 μmol (CHI-Succ-MNA-MNA 170) led to a 5.7-fold higher mucus viscosity than the non-thiolated control polymer (CHI-Succ) indicating a rheological synergism due to mucoadhesive properties. These results were confirmed by a second mucoadhesion study, which showed a significantly prolonged retention time of CHI-Succ-MNA-MNA on the small intestinal mucosa compared to CHI-Succ (P<0.02). Accordingly, the double preactivation seems to be a promising strategy in order to obtain entirely preactivated polymers with enhanced mucoadhesive properties.
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Affiliation(s)
- Claudia Menzel
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Jennifer Silbernagl
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Flavia Laffleur
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Christina Leichner
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Max Jelkmann
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Christian W Huck
- Center for Chemistry and Biomedicine, Institute of Analytical Chemistry and Radiochemistry, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Shah Hussain
- Center for Chemistry and Biomedicine, Institute of Analytical Chemistry and Radiochemistry, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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20
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Laffleur F, Fischer A, Schmutzler M, Hintzen F, Bernkop-Schnürch A. Evaluation of functional characteristics of preactivated thiolated chitosan as potential therapeutic agent for dry mouth syndrome. Acta Biomater 2015; 21:123-31. [PMID: 25900442 DOI: 10.1016/j.actbio.2015.04.016] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2014] [Revised: 04/02/2015] [Accepted: 04/14/2015] [Indexed: 10/23/2022]
Abstract
PURPOSE The objective of this study was to investigate preactivated thiomers for their potential in the treatment of dry mouth syndrome. METHODS Chitosan-thioglycolic-mercaptonicotinamide conjugates (chitosan-TGA-MNA) were synthesized by the oxidative S-S coupling of chitosan-thioglycolic acid (chitosan-TGA) with 6-mercaptonicotinamide (MNA). Test disks were compressed out of unmodified chitosan, chitosan-TGA (thiomers) and chitosan-TGA-MNA conjugates to investigate cohesive properties, cytotoxicity assays and mucoadhesion studies. RESULTS Immobilizing the MNA achieved higher swelling and cohesive properties of chitosan-TGA-MNA conjugates compared to unmodified chitosan. Rotating cylinder studies displayed a 3.1-fold improvement of mucoadhesiveness of chitosan-TGA-MNA conjugates compared to thiolated polymers. Findings in tensile strength were in good agreement with rotating cylinder ones. Furthermore, preactivated thiomers exhibit higher stability. All conjugates were found non-toxic against Caco-2 cells. CONCLUSION Preactivated thiolated chitosan could be a promising system for the treatment of dry mouth syndrome where mucosa requires lubrication and mucoadhesiveness.
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Bonengel S, Hauptstein S, Leonaviciute G, Griessinger J, Bernkop-Schnürch A. Thiolated alkyl-modified carbomers: Novel excipients for mucoadhesive emulsions. Eur J Pharm Sci 2015; 75:123-30. [PMID: 25857707 DOI: 10.1016/j.ejps.2015.03.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 03/18/2015] [Accepted: 03/19/2015] [Indexed: 11/22/2022]
Abstract
The aim of this study was the design and evaluation of mucoadhesive emulsifying polymeric excipients. Three thiol bearing ligands with increasing pKa values of their sulfhydryl group, namely 4-aminothiophenol (pKa=6.86), l-cysteine (pKa=8.4) and d/l-homocysteine (pKa=10.0) were coupled to the polymeric backbone of alkyl-modified carbomer (PA1030). Resulting conjugates displayed 818.5μmol 4-aminothiophenol, 698.5μmol cysteine and 651.5μmol homocysteine per gram polymer and were evaluated regarding the reactivity of thiol groups, emulsifying and mucoadhesive properties. In general, the synthesized conjugates showed a pH dependent reactivity, whereby the fastest oxidation occurred in PA1030-cysteine, as almost no free thiol groups could be detected after 120min. Emulsification of medium chain triglycerides was feasible with all synthesized conjugates leading to oil-in-water-emulsions. Emulsions with PA1030-cysteine displayed the highest stability and the smallest droplet size among the tested formulations. Oxidation and consequently cross-linking of the thiomers prior to the emulsification process led to an overall decreased emulsion stability. Evaluating mucosal residence time of thiomer emulsions on porcine buccal mucosa, a 9.2-fold higher amount of formulation based on PA1030-cysteine remained on the mucosal tissue within 3h compared to the unmodified polymer. According to these results, the highest reactive ligand l-cysteine seems to be most promising in order to obtain thiolated polymers for the preparation of mucoadhesive o/w-emulsions.
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Partenhauser A, Laffleur F, Rohrer J, Bernkop-Schnürch A. Thiolated silicone oil: synthesis, gelling and mucoadhesive properties. Acta Biomater 2015; 16:169-77. [PMID: 25660565 DOI: 10.1016/j.actbio.2015.01.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 12/18/2014] [Accepted: 01/16/2015] [Indexed: 02/07/2023]
Abstract
The aim of this study was the development of novel thiolated silicone oils and their evaluation with regard to gelling and mucoadhesive properties. A thiol coupling of 220 ± 14 and 127 ± 33 μmol/g polymer for 3-mercaptopropionic acid (MPA)- and cysteine-coupled silicone oil was determined, respectively. The dynamic viscosity of MPA–silicone raised significantly (p < 0.000001) after oxidation with iodine to a maximum of 523-fold within 1 h. During tensile studies, MPA–silicone showed both the highest results for total work of adhesion (TWA) and maximum detachment force (MDF) with a 3.8- and 3.4-fold increase, respectively, compared to the control. As far as the residence time on small intestinal mucosa is concerned, both silicone conjugates were detectable in almost the same quantities for up to 8 h with 56.9 ± 3.3 and 47.8 ± 8.9% of the initially applied conjugated silicone oil. Thiolated silicone oils can be regarded superior in comparison to commonly used silicone oils due to a prolonged retention time in the small intestine as site of action. Gelling and mucoadhesive features are advantageous for antiflatulent as well as mucoprotective biomaterials. Thus, these novel thiomers seem promising for an upgrade of currently available products for the treatment of dyspepsia, reflux oesophagitis and even inflammatory bowel diseases such as ulcerative colitis or Crohn’s disease.
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Abstract
Thiolated polymers or designated thiomers are obtained by immobilization of sulhydryl bearing ligands on the polymeric backbone of well-established polymers such as poly(acrylates) or chitosans. This functionalization leads to significantly improved mucoadhesive properties compared to the corresponding unmodified polymers, as disulfide bonds between thiol groups of thiomers and cysteine-rich glycoproteins of the mucus gel layer are formed. Furthermore, enzyme- and efflux-pump inhibiting as well as improved permeation-enhancing properties are advantages of thiolization. By the covalent attachment of mercaptonicotinamide substructures via disulfide bonds to thiolated polymers these properties are even substantially further improved and stability towards oxidation even in aqueous media can be provided. Meanwhile, more than 50 research groups worldwide are working on thiolated polymers. For certain thiomers the scale up process for industrial production has already been done and GMP material is available. Furthermore, safety of thiolated poly(acrylic acid), thiolated chitosan and thiolated hyaluronic acid could be demonstrated via orientating studies in human volunteers and via various clinical trials. The first product (Lacrimera® eye drops, Croma-Pharma) containing a chitosan-N-acetylcysteine conjugate for treatment of dry eye syndrome will enter the European market this year. It is the only product providing a sustained protective effect on the ocular surface due to its comparatively much more prolonged residence time worldwide. Various further products utilizing, for instance, thiolated hyaluronic acid in ocular surgery are in the pipeline.
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Affiliation(s)
- Sonja Bonengel
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innrain 80/82, 6020 Innsbruck, Austria.
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Bonengel S, Haupstein S, Perera G, Bernkop-Schnürch A. Thiolated and S-protected hydrophobically modified cross-linked poly(acrylic acid)--a new generation of multifunctional polymers. Eur J Pharm Biopharm 2014; 88:390-6. [PMID: 24960111 DOI: 10.1016/j.ejpb.2014.06.009] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2014] [Revised: 06/13/2014] [Accepted: 06/14/2014] [Indexed: 10/25/2022]
Abstract
The aim of this study was to create a novel multifunctional polymer by covalent attachment of l-cysteine to the polymeric backbone of hydrophobically modified cross-linked poly(acrylic acid) (AC1030). Secondly, the free thiol groups of the resulting thiomer were activated using 2-mercaptonicotinic acid (2-MNA) to provide full reactivity and stability. Within this study, 1167.36 μmol cysteine and 865.72 μmol 2-MNA could be coupled per gram polymer. Studies evaluating mucoadhesive properties revealed a 4-fold extended adherence time to native small intestinal mucosa for the thiomer (AC1030-cysteine) as well as an 18-fold prolonged adhesion for the preactivated thiomer (AC1030-Cyst-2-MNA) compared to the unmodified polymer. Modification of the polymer led to a higher tablet stability concerning the thiomer and the S-protected thiomer, but a decelerated water uptake could be observed only for the preactivated thiomer. Neither the novel conjugates nor the unmodified polymer showed severe toxicity on Caco-2 cells. Evaluation of emulsification capacity proofed the ability to incorporate lipophilic compounds like medium chain triglycerides and the preservation of the emulsifying properties after the modifications. According to these results thiolated AC1030 as well as the S-protected thiolated polymer might provide a promising tool for solid and semisolid formulations in pharmaceutical development.
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Affiliation(s)
- Sonja Bonengel
- Center for Chemistry and Biomedicine, Center for Molecular Biosciences, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - Sabine Haupstein
- Center for Chemistry and Biomedicine, Center for Molecular Biosciences, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - Glen Perera
- Center for Chemistry and Biomedicine, Center for Molecular Biosciences, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
| | - Andreas Bernkop-Schnürch
- Center for Chemistry and Biomedicine, Center for Molecular Biosciences, Department of Pharmaceutical Technology, Institute of Pharmacy, University of Innsbruck, Innsbruck, Austria
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Hintzen F, Hauptstein S, Perera G, Bernkop-Schnürch A. Synthesis and in vitro characterization of entirely S-protected thiolated pectin for drug delivery. Eur J Pharm Biopharm 2013; 85:1266-73. [PMID: 24095893 DOI: 10.1016/j.ejpb.2013.09.017] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 09/24/2013] [Accepted: 09/27/2013] [Indexed: 11/28/2022]
Abstract
The study was aimed to synthesize a thiolated polymer (thiomer) that is resistant to oxidation in solutions above pH 5. In order to protect a pectin-cysteine conjugate against premature oxidation, the thiomer was S-protected by a disulfide connected leaving group. Therefore, 2-mercaptonicotinic acid was first coupled to L-cysteine by a disulfide exchange reaction and the purified product was subsequently attached to pectin by a carbodiimide mediated amid bond formation. The obtained fully S-protected thiolated pectin was in vitro characterized with respect to co- and mucoadhesive properties and stability toward oxidation. The results indicated a 1.8-fold and 2.3-fold enhanced disintegration time at pH 6.8 of the S-protected thiolated pectin (Pec-Cys-MNA) compared to thiolated pectin (Pec-Cys) and unmodified pectin (Pec). Moreover, rheological measurements of polymer/mucus mixtures showed a 1.6-fold (compared to Pec-Cys) and 6.7-fold (compared to Pec) increased dynamic viscosity of Pec-Cys-MNA. On the other hand, in the presence of a strong oxidizing agent such as H2O2 (0.3% v/v), no increase in viscosity of Pec-Cys-MNA could be observed. A 6-month experiment also demonstrated the long-term stability of a liquid formulation based on Pec-Cys-MNA. Further investigations proved that the first time all thiol groups on a thiolated polymer could be protected owing to the novel synthesis. Accordingly, these features may help to develop thiomer based liquid or gel formulations targeting mucosal surfaces such as nasal, ocular or vaginal drug delivery systems.
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Affiliation(s)
- Fabian Hintzen
- Department of Pharmaceutical Technology, Institute of Pharmacy, Center for Molecular Biosciences, Leopold-Franzens-University Innsbruck, Center for Chemistry and Biomedicine, Innsbruck, Austria
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