An Evaluation of Biogenic Amorphous Silica Nanoparticles Synthesised from Spinifex Grass Waste for Targeted Doxorubicin Delivery

This project investigates the application of green nanotechnology for sustainable drug delivery systems. Specifically, it evaluates the biomedical potential of biogenic amorphous silica nanoparticles (bSNPs) synthesised from Spinifex grass waste (Triodia genus), a native perennial hummock grass widely distributed across the arid regions of Australia.
Conventional synthetic silica nanoparticles often face clinical limitations due to poor biodegradation kinetics and rapid immune clearance associated with protein corona formation. Spinifex grass naturally absorbs silicon and polymerises it exclusively into a highly hydrated, structurally disordered, and irregular amorphous state, their surface energies differ fundamentally from synthetic options. This study aims to determine whether the unique hydrated and plant-templated architecture of biogenic silica nanoparticles can provide enhanced biocompatibility, improved drug loading capacity, and more controlled release behaviour.
The chemotherapeutic agent doxorubicin (DOX) will be used as a model drug payload. The project will systematically investigate nanoparticle synthesis, extraction efficiency, physicochemical and porous structure characterisation, drug encapsulation performance, and in vitro release profiles. Comparative analyses will also be conducted against conventional silica nanoparticle systems.
This research seeks to establish a sustainable and environmentally friendly biogenic nanoplatform for targeted cancer drug delivery, while also contributing to the valorisation of Australian renewable biomass resources within a circular bioeconomy framework.

Aim  

The primary aim of this research is to synthesise, characterise, and evaluate biogenic amorphous silica nanoparticles extracted from Spinifex Grass to optimise the controlled delivery of Doxorubicin, and to assess their protein corona profiles and blood compatibility.

Objectives 

1. To isolate biogenic amorphous silica from Spinifex Grass using acid-leaching and controlled calcination techniques.
2. To verify the amorphous phase, particle diameter, morphology, and specific surface area using XRD, TEM, and BET analysis.
3. To map the hard protein corona, identifying whether the Spinifex-derived nanoparticles recruit “stealth” proteins (like Albumin) over “danger flags” (like Complement Factors)
4. To optimise the drug loading via packing Doxorubicin into the pore networks of biogenic platforms and calculate total encapsulation efficiency.
5. To evaluate the release kinetics by the passive diffusion profile of DOX from both matrices inside Simulated Body Fluid (SBF) at healthy pH (7.4) versus tumour pH (5.0 – 6.5).
6. To verify the biocompatibility of Spinifex-derived nanoparticles, an in vitro haemolysis assay will be conducted

Significance 

Bypassing Immune Clearance: This study will investigate the unique plant-templated surface properties of Spinifex-derived silica nanoparticles to understand their interactions with the protein corona and evaluate their potential as naturally stealth drug carriers with prolonged circulation times.
Overcoming Chemotherapy Toxicity: Free Doxorubicin is highly cardiotoxic; it blindly binds to cardiolipin receptors inside cardiac mitochondria and triggers an oxidative “free radical firestorm” that permanently damages heart tissue. Biogenic Spinifex silica nanoparticles will be engineered to preferentially accumulate in tumour tissues through the Enhanced Permeability and Retention (EPR) effect, potentially reducing the off-target toxicity and cardiotoxicity associated with free doxorubicin treatment.
Advancing Green Nanotechnology: Spinifex grass is an abundant and underutilised Australian biomass resource. Converting this renewable feedstock into high-value silica nanoparticles supports green chemistry principles, waste valorisation, and the development of sustainable nanomedicine platforms.

Ideal Candidate 

We are seeking a highly motivated PhD candidate with a background in Chemical Engineering, Biotechnology, Materials Science, Nanotechnology, Biomedical Engineering, Pharmaceutical Sciences, or a related discipline. The successful applicant should possess strong analytical, problem-solving, and research skills, with an interest in sustainable materials, nanomedicine, and drug delivery systems. Experience in laboratory-based research on nanoparticle synthesis, material characterisation, cell culture, or biomaterials is desirable but not essential. Excellent written and verbal communication skills, the ability to work independently and collaboratively, and eligibility for enrolment in a PhD program at Curtin University are required.

This project is open to International and Domestic applicants.  

Scholarship  

If you are identified as the preferred candidate for this project, you may be considered for an RTP scholarship. 

Enquires and How to Apply 

For enquires about this opportunity contact Dr Sufia Hena at Sufia.Hena@curtin.edu.au

To formally apply submit an Expression of Interest to Dr Sufia Hena during the Central Scholarship round (July 1st – July 31st 2026)