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S. A. Pauline
bone therapy purposes [97]. However, they suffer from certain disadvantages such
as limited chemical stability, local inflammatory reactions, improper drug-release
kinetics, etc. [71]. Bioactive calcium phosphates and bioactive glasses are widely
used as matrices in drug delivery systems. Mesoporous silica-titania composites
were developed to have ordered hexagonal array of pores. Antibiotic drug oxytetracycline was loaded onto the mesochannels by wetness impregnation method. Titania
present on the silica surface enabled the composite to hold oxytetracycline through
host-guest interaction and it avoided the initial burst release of the drug. It was
observed that by controlling the distribution of titanium in the silica network it was
possible to develop a drug delivery system with a controlled drug release profile
[42]. Zeolites with different silica to alumina ratio was used as delivery vehicle for
a chemotherapy drug, 5-fluorouracil. The molecular level interaction between the
drug and zeolite was confirmed by FTIR spectroscopy. Alumina content played a
key role in the drug release behavior and it was observed that greater the alumina
content better the controlled drug release behavior [89]. Orthopaedic implants can
also be coated with TiO 2 nanotubes that are loaded with anti-inflammatory drugs
like Ibuprofen and antibiotics like gentamycin or antibacterial drugs like cefuroxime
[99]. Thereby it is possible to control or prevent infection and inflammation without
affecting the bioactive behavior of implant material which supports the adhesion of
osteoblasts on to the implant surface [100].
4.4 Diagnostic Tools
The physicochemical properties of ceramic nanoparticles such as improved cellular
adhesion, greater osteoblast proliferation and increased biomineralization allow them
to be used as diagnostic tools in addition to effective drug delivery systems [99].
Nanoceramics such as porous silica nanoparticles, Fe 3 O 4 nanoparticles, quantum
dots, etc., are some examples that can be used in imaging, magnetic hyperthermia,
or photothermal ablation in addition to drug delivery systems [67]. Mesoporous
SiO 2 coated with europium hydroxide, Eu(OH) 3 core-shell microspheres were
used as a fluorescent probe for biomedical applications. FETEM confirmed that
SiO 2 nanospheres were covered evenly with luminescent Eu(OH) 3 . The microsphere emitted strong red emission peak when irradiated with ultraviolet light [101].
Composite film of Fe 3 O 4 /cellulose was prepared by co-dispersing Fe 3 O 4 particles
and cellulose in an aqueous solvent and then regenerating them. The composite film
was flexible, strong, had excellent mechanical property and thermal stability. The
composite film can sense towards UV light and magnetic field and can be used to
prepare sensors [102].
S. A. Pauline
bone therapy purposes [97]. However, they suffer from certain disadvantages such
as limited chemical stability, local inflammatory reactions, improper drug-release
kinetics, etc. [71]. Bioactive calcium phosphates and bioactive glasses are widely
used as matrices in drug delivery systems. Mesoporous silica-titania composites
were developed to have ordered hexagonal array of pores. Antibiotic drug oxytetracycline was loaded onto the mesochannels by wetness impregnation method. Titania
present on the silica surface enabled the composite to hold oxytetracycline through
host-guest interaction and it avoided the initial burst release of the drug. It was
observed that by controlling the distribution of titanium in the silica network it was
possible to develop a drug delivery system with a controlled drug release profile
[42]. Zeolites with different silica to alumina ratio was used as delivery vehicle for
a chemotherapy drug, 5-fluorouracil. The molecular level interaction between the
drug and zeolite was confirmed by FTIR spectroscopy. Alumina content played a
key role in the drug release behavior and it was observed that greater the alumina
content better the controlled drug release behavior [89]. Orthopaedic implants can
also be coated with TiO 2 nanotubes that are loaded with anti-inflammatory drugs
like Ibuprofen and antibiotics like gentamycin or antibacterial drugs like cefuroxime
[99]. Thereby it is possible to control or prevent infection and inflammation without
affecting the bioactive behavior of implant material which supports the adhesion of
osteoblasts on to the implant surface [100].
4.4 Diagnostic Tools
The physicochemical properties of ceramic nanoparticles such as improved cellular
adhesion, greater osteoblast proliferation and increased biomineralization allow them
to be used as diagnostic tools in addition to effective drug delivery systems [99].
Nanoceramics such as porous silica nanoparticles, Fe 3 O 4 nanoparticles, quantum
dots, etc., are some examples that can be used in imaging, magnetic hyperthermia,
or photothermal ablation in addition to drug delivery systems [67]. Mesoporous
SiO 2 coated with europium hydroxide, Eu(OH) 3 core-shell microspheres were
used as a fluorescent probe for biomedical applications. FETEM confirmed that
SiO 2 nanospheres were covered evenly with luminescent Eu(OH) 3 . The microsphere emitted strong red emission peak when irradiated with ultraviolet light [101].
Composite film of Fe 3 O 4 /cellulose was prepared by co-dispersing Fe 3 O 4 particles
and cellulose in an aqueous solvent and then regenerating them. The composite film
was flexible, strong, had excellent mechanical property and thermal stability. The
composite film can sense towards UV light and magnetic field and can be used to
prepare sensors [102].