title: Evaluation of dysprosia aerogels as drug delivery systems: a comparative study with random and ordered mesoporous silicas.
abstract: Biocompatible dysprosia aerogels were synthesized from DyCl3·6H2O and were reinforced mechanically with a conformal nano-thin-polyurea coating applied over their skeletal framework. The random mesoporous space of dysprosia aerogels was filled up to about 30% v/v with paracetamol, indomethacin, or insulin, and the drug release rate was monitored spectrophotometrically in phosphate buffer (pH = 7.4) or 0.1 M aqueous HCl. The drug uptake and release study was conducted comparatively with polyurea-crosslinked random silica aerogels, as well as with as-prepared (native) and polyurea-crosslinked mesoporous silica perforated with ordered 7 nm tubes in hexagonal packing. Drug uptake from random nanostructures (silica or dysprosia) was higher (30-35% w/w) and the release rate was slower (typically >20 h) relative to ordered silica (19-21% w/w, <1.5 h, respectively). Drug release data from dysprosia aerogels were fitted with a flux equation consisting of three additive terms that correspond to drug stored successively in three hierarchical pore sites on the skeletal framework. The high drug uptake and slow release from dysprosia aerogels, in combination with their low toxicity, strong paramagnetism, and the possibility for neutron activation render those materials attractive multifunctional vehicles for site-specific drug delivery.
authors.affiliation: Department of Chemistry, Missouri University of Science and Technology , Rolla, Missouri 65409, United States.
authors.forename: Abhishek
authors.initials: A
authors.lastname: Bang
authors.forename: Anand G
authors.initials: AG
authors.lastname: Sadekar
authors.forename: Clayton
authors.initials: C
authors.lastname: Buback
authors.forename: Brice
authors.initials: B
authors.lastname: Curtin
authors.forename: Selin
authors.initials: S
authors.lastname: Acar
authors.forename: Damir
authors.initials: D
authors.lastname: Kolasinac
authors.forename: Wei
authors.initials: W
authors.lastname: Yin
authors.forename: David A
authors.initials: DA
authors.lastname: Rubenstein
authors.forename: Hongbing
authors.initials: H
authors.lastname: Lu
authors.forename: Nicholas
authors.initials: N
authors.lastname: Leventis
authors.forename: Chariklia
authors.initials: C
authors.lastname: Sotiriou-Leventis
mesh_terms: D000082:Acetaminophen / Q000737:chemistry* / Q000494:pharmacology; D001792:Blood Platelets / Q000187:drug effects / Q000502:physiology; D004337:Drug Carriers / Q000737:chemistry*; D016503:Drug Delivery Systems / Q000295:instrumentation*; D004419:Dysprosium / Q000737:chemistry*; D005782:Gels / Q000737:chemistry; D006801:Humans; D007213:Indomethacin / Q000737:chemistry* / Q000494:pharmacology; D007328:Insulin / Q000737:chemistry* / Q000494:pharmacology; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*
chemical_list: D004337:Drug Carriers; D005782:Gels; D007328:Insulin; D004419:Dysprosium; D000082:Acetaminophen; D012822:Silicon Dioxide; D007213:Indomethacin; C030582:dysprosium oxide