Controlled release nano-termiticide formulation
Chemical treatment is used extensively to protect buildings from termite infestation. Current termiticide formulations have faced several limitations that influence their termiticidal efficacy, for example limited soil penetration capacity and limited (<15 years) lifetimes. Therefore there is a need for a long-life chemical barrier technology that can better penetrate soil, and which possesses the ability to become active only after a period of weeks following application to ensure termites escape the building prior to activation.
Researchers at The University of Queensland have developed a nano-formulation technology that has the potential to solve the application and synthesis problems described. The technology utilises a cheap, commercially available precursor material that avoids the need for expensive surfactants or chemical reactions. The nano-formulation technology has a high loading capacity of active ingredient in its nano-dispersed form (ie no aggregation/formation of large crystals is observed). The technology can be used to precisely control the release rate and can enhance the soil penetration of the active ingredient.
Key Features
- Scalable, cheap and facile synthesis of nano-termiticide formulations
- High loading capacity of active ingredients without aggregation/crystallisation
- Applicable to different active ingredients, eg bifenthrin, fipronil
- Precisely controllable release rate and enhanced soil penetration.
Silica nanocapsules
Silica micro-nanocapsules for controllable sustained release of active ingredients, including delicate biologics.
Designed peptide or protein surfactants are used typically to generate an oil in water nanoemulsion. The surfactant also incorporates a mineralising peptide sequence. In the presence of a silica source, this mineralising component facilitates the formation of a silica shell to encapsulate the nanodroplet containing the active ingredient. The nanometer thickness of the silicate shell can be regulated which, in turn, allows the rate of active ingredient release to be controlled if required. This encapsulation technology has been applied to coating microbes and could be used to protect them from processing or storage conditions.
It is also possible to control the surface chemistry and texture – there is scope to initiate release in response to pH.
Initial cost analyses suggest that this encapsulation approach will be low cost.
Potential applications
- Agriculture, veterinary, pest control, functional packaging
- Sustained or triggered release of active ingredients, including small molecules and bioactives
- Encapsulation of delicate actives (eg microbes) to provide temporary protection prior to release.
High loading core shell nanoparticles
Approximately 40% of approved drugs and 90% of pipeline drugs exhibit poor water solubility, which often leads to low drug efficacy. In biomedical applications, biodegradable polymer nanoparticles can be particularly useful in formulating poorly soluble drugs for improved bioavailability, safety, tolerability and efficacy. However, among various polymer nanoparticle systems, drug loading is usually below 10% which hinders their practical applications.
Researchers at The University of Queensland have developed new approaches for the synthesis of polymer (eg. PLGA, PLGA-PEG, PLA-PEG, shellac) nanoparticles encapsulating insoluble small molecule drugs (eg. paclitaxel, docetaxel, curcumin, amphotericin B, Scutellarin, Bulleyaconitine A, ibuprofen, ketamine, imaging agents Dil and DiO). These methods allow for the improved control of polymer formation around drug nanoparticle cores whilst avoiding the formation of aggregates.
Key features
- Preparation of core-shell nanoparticles with up to 58.5% drug loading
- Simple, reproducible method that enables good particle size control and stability.
Potential application
- Encapsulation of insoluble small molecule drugs
- Formulation of active ingredients for animal health and agrichemical applications
- Encapsulation of imaging agents.
Pesticide formulation technology
The pesticide formulation technology comprises silica carrier particles that encapsulate active ingredients (AI) to provide UV protection, increased rainfastness and easier formulation of hydrophobic AI.
Key features
- Small molecule or biologic actives are loaded into silica microcapsules
- Loaded molecules are protected from UV degradation by the capsule
- ‘Hairy’ microcapsule surface enhances leaf adhesion to minimise wash-off, increase utilisation of actives with potential for label dose reduction
- Hydrophobic molecules are easily loaded.
Engineered nano-clay for agriculture application
The natural nitrogen cycle has a number of avoidable losses through leaching and run-off of nitrate into waterways, and nitrous oxide emissions. Modern agriculture is driving the demand for higher levels of nitrogen than what is found in native soils, which is addressed by application of nitrogen fertilisers.
However, frequent fertilizer application leads to enormous economic costs and environmental burdens associated with nutrient pollution and greenhouse gas emissions. Thus, strategies must be developed for improving nitrogen use efficiency. Clay-based soil amendments can help with the environmental sustainability, technical effectiveness of restoring degraded soils and enhancing crop yields.
Key Features
- Simple, cost-effective method for preparing sub-micron sized clay particles
- Enhanced ammonia immobilisation capacity and high loading of nitrification
inhibitor; minimize N leaching and N2O emission - Enhanced soil fertility, nutrient retention capacity, and the capacity to protect groundwater from cation leaching.
