Silica xerogel as an implantable carrier for controlled drug delivery—evaluation of drug distribution and tissue effects after implantation

Kortesuo, Pirjo; Ahola, Manja; Karlsson, Stefan; Kangasniemi, Ilkka; Yli‐Urpo, Antti; Kiesvaara, Juha

doi:10.1016/s0142-9612(99)00148-9

Cited by 242 publications

(115 citation statements)

References 15 publications

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“…50,52 Other studies investigating the use of silica xerogel for drug delivery reported that silica xerogels exhibited a weight loss of about 30% after several days in simulated body fluid. [53][54][55] In our study, the loss was 80% after 30 minutes -in comparison, a very fast exchange. Assuming that the silica matrix would be dissolved and not exchanged, the residual HA crystals would delaminate.…”

Section: Discussionsupporting

confidence: 43%

In vivo and in vitro investigations of a nanostructured coating material – a preclinical study

Adam¹,

Ganz²,

Xu³

et al. 2014

IJN

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Immediate loading of dental implants is only possible if a firm bone-implant anchorage at early stages is developed. This implies early and high bone apposition onto the implant surface. A nanostructured coating material based on an osseoinductive bone grafting is investigated in relation to the osseointegration at early stages. The goal is to transmit the structure (silica matrix with embedded hydroxyapatite) and the properties of the bone grafting into a coating material. The bone grafting substitute offers an osseoinductive potential caused by an exchange of the silica matrix in vivo accompanied by vascularization. X-ray diffraction and transmission electron microscopy analysis show that the coating material consists of a high porous silica matrix with embedded nanocrystalline hydroxyapatite with the same morphology as human hydroxyapatite. An in vitro investigation shows the early interaction between coating and human blood. Energy-dispersive X-ray analysis showed that the silica matrix was replaced by an organic matrix within a few minutes. Uncoated and coated titanium implants were inserted into the femora of New Zealand White rabbits. The bone-to-implant contact (BIC) was measured after 2, 4, and 6 weeks. The BIC of the coated implants was increased significantly at 2 and 4 weeks. After 6 weeks, the BIC was decreased to the level of the control group. A histological analysis revealed high bone apposition on the coated implant surface after 2 and 4 weeks. Osteoblastic and osteoclastic activities on the coating material indicated that the coating participates in the bone-remodeling process. The nanostructure of the coating material led to an exchange of the silica matrix by an autologous, organic matrix without delamination of the coating. This is the key issue in understanding initial bone formation on a coated surface.

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Section: Discussionsupporting

confidence: 43%

In vivo and in vitro investigations of a nanostructured coating material – a preclinical study

Adam¹,

Ganz²,

Xu³

et al. 2014

IJN

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“…15 To Gels containing replication-deficient adenovirus coding for LacZ were placed in a 24-well cell culture plate and incubated in PBS for the indicated number of days, after which HSF cells were added to the wells. Three days later, cells were stained with X-gal (green).…”

Section: Silica Biodegradation and Release Of Functional Virus In Vivomentioning

confidence: 99%

“…The material is biodegradable in vivo and is subsequently secreted into urine. 15 Biodegradation is the main mechanism controlling the release rate of large encapsulates in vitro and is flexibly adjustable to the desired degradation rate. 16 Combining anticancer agents into an implantable and degradable delivery matrix attempts to modify drug biodistribution, reduce drug toxicity and thus improve therapeutic efficacy.…”

Section: Introductionmentioning

confidence: 99%

Extended release of adenovirus from silica implants in vitro and in vivo

et al. 2008

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Despite promising preclinical results, the clinical benefits of cancer gene therapy have been modest heretofore. The main obstacle continues to be the level and persistence of gene delivery to sufficiently large areas of the tumor. One approach for overcoming this might entail extended local virus release. We studied the utility of silica gel monoliths for delivery of adenovirus to advanced orthotopic gastric and pancreatic cancer tumors. Initially, the biochemical properties of the silica-virus matrix were studied and nearly linear release as a function of time was detected. Virus stayed infective for weeks at +37 1C and months at +4 1C, which may facilitate storage and distribution. In vivo, extended release of functional replication deficient and also replication-competent, capsid-modified oncolytic viruses was seen. Treatment of mice with pancreatic cancer doubled their survival ( Po0.001). Also, silica gel-based delivery slowed the development of antiadenovirus antibodies.

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“…The reports [10,39,40], which exhibit biocompatibility and bioactivity sol-gel ceramics combined with this study, suggest that these xerogel materials could be promising candidates for formulation in local delivery systems as controlled release materials for the treatment of bone infections or for repairing periodontal defects in dentistry.…”

Section: Discussionmentioning

confidence: 56%

Sol–gel-processed silica/polydimethylsiloxane/calcium xerogels as polymeric matrices for Metronidazole delivery system

Czarnobaj

2010

Polym. Bull.

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Silica, silica/polydimethylsiloxane and silica/polydimethylsiloxane/ calcium xerogels were examined as polymeric carriers for the controlled release of drug-Metronidazole. Characterization assays comprised analysis of the matrix by Fourier transform infrared spectroscopy (FTIR), determining the specific surface area of solids (BET) and scanning electron microscope (SEM) techniques and further monitoring in the ultraviolet and visible light regions (UV-Vis) of the in vitro release of the drug over time. Using tetramethoxysilane (TMOS) as a precursor of silica matrix and polydimethylsiloxane (PDMS) and calcium ions as additives, xerogels with different morphology and physical properties were obtained. The applied modifications diminished the porosity and hydrophilicity of the silica matrix as well as reduced the release of drug. Based on the presented results of this study, it may be stated that applied xerogel matrices, pure silica (SiO 2 ) and modified silica (SiO 2 -CaO, SiO 2 -PDMS and SiO 2 -CaO-PDMS), could be promising candidates for the formulation in local delivery systems.

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Silica xerogel as an implantable carrier for controlled drug delivery—evaluation of drug distribution and tissue effects after implantation

Cited by 242 publications

References 15 publications

In vivo and in vitro investigations of a nanostructured coating material – a preclinical study

In vivo and in vitro investigations of a nanostructured coating material – a preclinical study

Extended release of adenovirus from silica implants in vitro and in vivo

Sol–gel-processed silica/polydimethylsiloxane/calcium xerogels as polymeric matrices for Metronidazole delivery system

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Silica xerogel as an implantable carrier for controlled drug delivery—evaluation of drug distribution and tissue effects after implantation

Cited by 242 publications

References 15 publications

In vivo and in vitro investigations of a nanostructured coating material &ndash; a preclinical study

In vivo and in vitro investigations of a nanostructured coating material &ndash; a preclinical study

Extended release of adenovirus from silica implants in vitro and in vivo

Sol–gel-processed silica/polydimethylsiloxane/calcium xerogels as polymeric matrices for Metronidazole delivery system

Contact Info

Product

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In vivo and in vitro investigations of a nanostructured coating material – a preclinical study

In vivo and in vitro investigations of a nanostructured coating material – a preclinical study