Formulation vessel
Clean sample vials
Labelled storage containers
Dispensing tips
Magnetic stir bar
Microcentrifuge tubes
Gloves and laboratory wipes
NSL Modules Used
Sterilization UV
Reservoir Dispense
Stirrer
Heater
Wait
Sonicator
Sonicator Bath Heater
LED Illumination
UV Illumination, if required only for chamber illumination or visual demonstration
IR Illumination, if required for camera observation
Camera
Exhaust
Environment Sensors
Offline / Manual / External Steps
Magnetic separation or centrifugation
Detailed washing and resuspension
p H measurement or adjustment confirmation
Particle size analysis
Zeta potential measurement
FTIR or surface chemistry analysis
XRD or crystallinity analysis
VSM or magnetic characterization
Microscopy such as SEM/TEM
Cytotoxicity testing
Cellular uptake or imaging validation
Magnetic hyperthermia evaluation
Sterility and endotoxin testing
Methods: NSL-Compatible and Protoly-Managed Steps
Step 1: Sterilization UV
Module: Sterilization UV
Function: Timed UV sterilization cycle
Suggested Duration: 5 minutes
Description: Run a UV sterilization cycle before starting nanoparticle conditioning. This supports chamber preparation before automated liquid handling and mixing.
Step 2: Chamber Environment Record
Module: Environment Sensors
Function: Ambient chamber environment logging
Description: Record the initial chamber condition before the conditioning run. This information may be useful when comparing dispersion behaviour across batches.
Step 3: Chamber Illumination
Module: LED Illumination
Function: White light chamber illumination
Description: Turn on LED illumination to support camera-based observation of dispersion appearance, colour, visible settling, and aggregation during the workflow.
Step 4: Load Iron Oxide Nanoparticle Dispersion
Step Type: Manual / pre-run loading step
Description: Place the pre-prepared iron oxide nanoparticle dispersion in the formulation vessel before starting the automated sequence. If the particles are supplied as powder, initial wetting and safe dispersion should be performed carefully before loading.
Step 5: Dispense Dilution or Washing Medium
Module: Reservoir Dispense
Reagent: Deionized water or buffer
Suggested Volume: 100-300 u L, or as per formulation scale
Channel: 1
Description: Dispense deionized water or buffer into the vessel to dilute or support resuspension of the iron oxide nanoparticle dispersion.
Step 6: Controlled Stirring
Module: Stirrer
Mode: Continuous
Suggested RPM: 300-600
Description: Start stirring to distribute the nanoparticles uniformly in the aqueous medium. Moderate stirring helps reduce settling while avoiding excessive vortexing or splashing.
Step 7: Optional Mild Heating
Module: Heater
Suggested Temperature: 30-45 °C
Suggested Duration: 10-30 minutes
Description: Apply mild heating only if required to improve coating-agent interaction or dispersion uniformity. Temperature should be selected based on the stability of the nanoparticle coating and any added biomolecule or model ligand.
Step 8: Dispense Stabilizing Solution
Module: Reservoir Dispense
Reagent: Stabilizing solution
Suggested Volume: 20-100 u L
Channel: 2
Description: Add the selected stabilizing solution, such as citrate, dextran, PEG-containing solution, chitosan, PVA, or another research-compatible stabilizer. The choice depends on the intended downstream model study.
Step 9: Mixing After Stabilizer Addition
Module: Stirrer
Mode: Continuous
Suggested RPM: 300-500
Suggested Duration: 15-30 minutes
Description: Continue stirring to allow uniform contact between the stabilizing agent and nanoparticle surface. This step supports preliminary surface conditioning and dispersion stabilization.
Step 10: Dispense Surface-Conditioning or Coating Solution
Module: Reservoir Dispense
Reagent: Surface-conditioning or coating solution
Suggested Volume: 20-100 u L
Channel: 3
Description: Add the selected surface-conditioning or coating solution according to the research design. This step may prepare the nanoparticles for later bio-interface, targeting, imaging, or drug-delivery model studies.
Step 11: Conditioning Hold
Module: Wait
Suggested Duration: 30-90 minutes
Description: Allow the nanoparticle dispersion and conditioning agent to remain in contact for a defined period. This waiting step supports coating interaction, adsorption, or stabilization depending on the selected chemistry.
Step 12: Gentle Mixing During Conditioning
Module: Stirrer
Mode: Intermittent or continuous
Suggested RPM: 200-400
Suggested Duration: 10-20 minutes
Description: Use gentle mixing during or after the conditioning hold to prevent settling and maintain uniform dispersion without causing unnecessary foaming or mechanical stress.
Step 13: Optional Sonication for Dispersion Improvement
Module: Sonicator
Suggested Duration: 1-5 minutes
Condition: Optional
Description: Apply mild sonication if visible aggregation or settling is observed. Sonication should be optimized carefully because excessive sonication may heat the sample or disturb surface-bound molecules.
Step 14: Optional Sonicator Bath Heating
Module: Sonicator Bath Heater
Suggested Temperature: 30-40 °C
Condition: Optional
Description: Use sonicator bath heating only when temperature support is required during sonication. Avoid excessive heating for biomolecule-containing conditioning systems.
Step 15: Stabilization Hold
Module: Wait
Suggested Duration: 30-60 minutes
Description: Allow the conditioned nanoparticle dispersion to stabilize after mixing and optional sonication. This helps observe whether the dispersion remains uniform or begins to settle.
Step 16: Visual Documentation
Modules: LED Illumination and Camera
Function: Visual documentation
Description: Record the final dispersion appearance using LED illumination and camera support. Observe colour uniformity, visible aggregation, sedimentation, foam, and clarity of the dispersion. This is visual documentation only, not quantitative optical spectroscopy.
Step 17: Exhaust Control
Module: Exhaust
Mode: As required
Description: Use exhaust control during handling if volatile, acidic, or odorous conditioning components are involved. Any hazardous chemical handling should follow laboratory safety requirements.
Step 18: Manual Sample Collection and Labelling
Step Type: Manual / offline step
Description: Remove the conditioned dispersion from the system and transfer it into a clean labelled vial. Record batch ID, nanoparticle source, stabilizer type, conditioning agent, mixing time, sonication time, and visual observations.
Step 19: Offline Washing or Separation
Step Type: Manual / external step
Description: If required, perform magnetic separation, centrifugation, or washing externally to remove excess conditioning agent or unbound molecules. This is not an NSL module and should be documented as an external process.
Step 20: External Characterization
Step Type: Offline / external step
Description: Characterize the conditioned nanoparticles using suitable external methods such as DLS, zeta potential, FTIR, XRD, VSM, microscopy, magnetic response testing, cytotoxicity, cellular uptake, or imaging model studies, depending on the project objective.
Methodology
The surface-conditioned iron oxide nanoparticle dispersion was prepared using a Protoly-managed workflow supported by selected NSL hardware modules. Before the automated run, a pre-prepared iron oxide nanoparticle dispersion was placed in the formulation vessel. If the nanoparticle material was supplied as a dry powder or concentrated stock, initial safe dispersion or wetting was performed before loading into the NSL-compatible vessel.
The chamber was subjected to a timed UV sterilization step, followed by recording of the initial ambient chamber condition using the environment sensor module. White LED illumination was activated to support camera-based monitoring. Deionized water or buffer was dispensed into the vessel using the reservoir dispensing module to dilute or resuspend the nanoparticle dispersion. Controlled stirring was then started to maintain a uniform suspension.
A stabilizing solution such as citrate, dextran, PEG-containing solution, chitosan, PVA, or another selected conditioning agent was dispensed into the nanoparticle dispersion. Depending on the formulation design, mild heating was applied to support uniform interaction between the nanoparticle surface and the conditioning agent. The dispersion was stirred for a defined period and then held for surface-conditioning time.
If required, an additional coating or functionalization-compatible solution was dispensed into the vessel. Gentle stirring was continued to maintain dispersion uniformity. Optional sonication was applied only when dispersion improvement was required, and sonicator bath heating was used only where temperature support was suitable. After conditioning, the dispersion was held for stabilization and visually documented using LED illumination and the camera module.
The final conditioned nanoparticle dispersion was manually collected into a clean labelled vial. Offline washing, magnetic separation, centrifugation, or purification was performed where required. The sample was then reserved for external characterization such as size analysis, zeta potential, surface chemistry evaluation, magnetic response testing, microscopy, imaging model studies, cytotoxicity evaluation, or other theranostic model assessments. This workflow is intended for research-scale conditioning and does not represent a validated diagnostic or therapeutic nanoparticle manufacturing process.