Encapsulation technologies A general overvie - Capsulae.pdf · Capsulæ / Encapsulation technologies - Capsulae 3 Introduction Encapsulation: definition and concepts Encapsulation

Encapsulation technologies: A general overview

© Capsulae

Introduction • Definition of encapsulation• Objectives and markets

Encapsulation technologies • Dripping• Spray-drying• Prilling• Coating• Emulsion / Stabilization

Characterizations • Particle size measurements• Microscopy• Thermo-mechanical properties• Powder properties• Microbiology• Quantification, release kinetic profiles

Conclusion • Selection of a technology• Industrialization • Capsulæ, company and services

Presentation outline

3 Capsulæ / Encapsulation technologies - © Capsulae

www.capsulae.com

Introduction

Encapsulation: definition and concepts

Encapsulation relates to technologies which enable to formulate one active compound (or more), inside individualized particles with a specific geometry and properties.

Terminology: encapsulation, microencapsulation, or nanoencapsulation? • Encapsulation defines no size notion• Microencapsulation usually refers to sizes ranging

from 1 µm to 1 mm• Nanoencapsulation is used for nanometric sizes but

sometimes refers to sizes ranging up to 1 µm or few micrometers

The current presentation focuses on sizes ranging from 1 µm to few millimeters.

1. Introduction

DefinitionsObjectives

Markets

2. Technologies3. Analyses

4. Conclusion


www.capsulae.com

Introduction

Encapsulation: definition and concepts Structures of particles:

• Matrix structure: dispersion of active compound(s) in the encapsulation material (beads, microparticles, microspheres)

• Core / shell structure: the active compound (pure or not) is confined as one core by one shell or more (multi-shell) (microparticles, microcapsules)

• Both structure can be combined to design new ones: (matrix core) / shell, or core / (matrix shell) (two compounds, one in the core and another one in the shell)…

Matrix structure, active(s) in orange

Matrix structure particle with clearly

visible active

Core / shell structure, active(s) in orange

Shell of capsule containing

a liquid core

1. Introduction


Markets


4. Conclusion


www.capsulae.com

Introduction

Encapsulation: definition and concepts Active compounds:

• Physical state: solid, liquid, gas• Hydrophilic or hydrophobic• Granulometry (powder, particle): up to few mm• Active compound content up to 900 mg per g of final particle

Encapsulation materials (non exhaustive list):

• Biopolymers (vegetable, animal or bacterial sources): alginates, pectins, chitosans, carrageenans, Arabic gums, cellulose derivatives, starches, gelatins, milk proteins, gellan gum, …

• Waxes and fats (vegetable, animal sources): carnauba wax, candelilla wax, stearins, shellac…

• Surfactants: lecithins, Spans®, Tweens®…• Synthetic polymers: PVA, PEG, polycaprolactone, PLGA, isocyanates,

polyamide, polyurea, polyurethane, melamine formaldehyde…

The appropriate grade shall be selected:

• Food• Feed• Cosmetic• Pharma• Others

1. Introduction


Markets


4. Conclusion


www.capsulae.com

Introduction

Encapsulation: objectives (1/2) Encapsulating an active principle meets four main objectives which can be combined.

Immobilization:

• Volatile compounds (e.g. fragrances, flavors)• Continuous bioprocessing

(e.g. enzymes, micro organisms)

Protection / Stabilization:

• Stabilize and protect the active ingredient against external environemental factors (e.g. O2, light, T°C H2O, pH)

• Protect handlers and consumers (e.g. detergent proteases, pesticides)

1. Introduction


Markets


4. Conclusion

Encapsulation of essential oil in biopolymer beads

Lyophilisate without (up) and with coating (down)


www.capsulae.com

Introduction

Encapsulation: objectives (2/2) Controlled release (at a given time, upon the action of a selected trigger) :

• Diffusion, rehydration, degradation, rupture• Triggered release by a specific condition

(chemical, physical, mechanical factor): temperature, pH value, water, pressure…

• Sustained release with specific kinetics profiles (e.g. vitamins, drugs, flavors, pesticides)

Structuration / Functionalization:

• Conversion of liquid or gas to solid• Taste, odor or color masking• Surface properties and rheology of powders;

dust free powder• Visual aspect and marketing concept

1. Introduction


Markets


4. Conclusion Salt release in aqueous solution (microsphere)

Samples produced using different encapsulation

technologies


www.capsulae.com

1. Introduction


Markets


4. Conclusion

Introduction

Encapsulation: markets Microencapsulation can be applied to all sectors of industrial activity: Food & Feed • Flavouring agents & sweeteners• Enzymes & micro-organisms• Vitamins, minerals & amino acids• Plant extracts,

aromas, fragrances• Unsaturated fatty acids

Agriculture & Environment • Insecticides and fungicides• Herbicides and fertilizers• Repellents and larvicides • Plant biocontrol & bionutrition• Water, soil, air treatment

Home & Personal Care • Cosmetic creams • Shampoo, toothpaste,

soap & shower gels• Washing powders

& washing-up liquids• Household products

Chemistry • Adhesives and sealants• Paints and coatings• Building & construction

materials• Self-healing materials

& PCM

Human & Animal Health • Vaccination & drug delivery• Artificial insemination• Bioartificial organs• Cell therapy


www.capsulae.com

Encapsulation processes

General principe

1. Incorporation of the active ingredient within the microparticles

• Liquid core (active ingredient dissolved or dispersed in water, organic solvent, oil or melt; solution, emulsion, suspension)• Solid core (active ingredient available as powder, crystals, or liquid adsorbed on inert particles)

2. Dispersion (liquid core) or Agitation & spraying (solid core)

• Liquid core (formation of droplets via liquid/liquid or liquid/air dispersion): droplet extrusion (dripping), spraying, or emulsification• Solid core (spraying of coating material on particles under agitation; coating, layering, agglomeration): fluid bed coating, pan/drum coating

3. Stabilization of droplets (liquid core) or film formation (solid core)

• Solidification / Crystallization• Solvent evaporation or drying• Gelation (thermal, ionotropic)• Polymerization (in-situ or interfacial), Polycondensation • Precipitation / Coacervation (simple or complex) / Reticulation

1. Objectives

2. Technologies

General principleDripping

Spray-dryingPrillingCoating

Emulsion

3. Analysis4. Conclusion


www.capsulae.com


Dripping / gelation technologies:

Methods: droplet extrusion (single or multi nozzle device, simple gravity, spinning disk, jet breakage systems, co-extrusion) of a (bio)polymer solution in a gelation bath or in ambient/cold air

Particles properties (standard):

• Size range: from 50 µm to 7-8 mm• Final state: wet (can be dried or lyophilized) • Active type: liquid, solid; hydrophilic or lipophilic• Active content: up to 400 mg/g (wet), 900 mg/g (dry)• Structure: matrix, core / shell (s), (matrix core) / shell

Main advantage(s):

• Biocompatibility• Low particle size distribution

Possible limitation(s):

• Diffusion through the biopolymer network / membrane

1. Objectives

2. Technologies



Emulsion


Dripping(multiple nozzles)

Vibrating jet breakage (up) and spinning disk device (down)


www.capsulae.com


Spray-drying Method: spraying of an aqueous solution in hot air


• Size range: from 10 µm to 200 µm• Final state: dry • Active type: liquid, solid; hydrophilic or lipophilic• Active content: up to 400 mg/g• Structure: matrix

Main advantage(s):

• Very high productivity


• Thermal degradation

1. Objectives

2. Technologies



Emulsion


10 µm

Spray-dried powder (encapsulated PUFA)

SEM observation of microparticles produced

by spray-drying


www.capsulae.com


Prilling (spray-cooling or spray-congealing): Method: formation of droplets by spraying of hot-melt material containing the active and solidification in ambient / cool air

Particles properties (standard): • Size range: from 50 µm to 500 µm• Final state: dry • Active type: solids or lipophilic liquid • Active content: up to 400 mg/g• Structure: matrix

Main advantage(s): • Very high productivity• Size control


• Thermal degradation

1. Objectives

2. Technologies



Emulsion


Encapsulated minerals

Encapsulated vitamins


www.capsulae.com


Coating technologies: Method: spraying (top-spray, bottom-spray and tangential-spray) of an aqueous solution or a hot-melt material on particles under agitation (fluid-bed coating or drum/pan coating)


• Size range: from 100 µm to 5 mm• Final state: dry • Active type: solid or liquid adsorbed on a support • Active content: up to 900 mg/g• Structure: core / shell(s)

Main advantage(s):

• Control of final particle size and coating thickness• High active content


• Support properties

1. Objectives

2. Technologies



Emulsion


1 mm

SEM observation of sections of coated minerals

Fluid-bed coating (bottom-spray)


www.capsulae.com


Emulsion / Stabilization technologies: Methods: stabilization of droplets formed by emulsion (o/w, w/o, double emulsion) by coacervation, reticulation, thermal gelation, solidification, interfacial or in-situ polymerization, solvent evaporation


• Size range: from 1 µm to 500 µm (nanometric size can be achieved)• Final state: wet (slurry); can be spray-dried or lyophilized• Active type: soluble in hydrophilic or hydrophobic liquids• Actif content: up to 900 mg/g• Structure: core / shell(s)

Main advantage(s):

• High active content• Small size


• High-shear process

1. Objectives

2. Technologies



Emulsion


20 µm

Particles prepared by double emulsion (w/o/w)

Particles prepared by o/w emulsion and interfacial

polymerization


www.capsulae.com

Analysis

Size measurements: particle size distribution • Laser diffraction (dry state or solution):

from 1 µm to few millimeters• Dynamic light scattering / zeta potential:

from 1 nm to 10 µm

Microscopy: structure and surface observation

• Scanning Electron Microscopy (SEM): surface observations• Binocular, optical microscope (bright or dark field),

fluorescence, confocal

1. Objectives

2. Technologies

3. Analysis

Size measurementsMicroscopy

Thermo-mechanical properties

Powder propertiesMicrobiology

Quantification

4. Conclusion

10 µm

Minerals inside microparticles of fatty acids

(optical microscopy)

Surface of microparticles produced by emulsion /

solidification (SEM)

Fluorescent confocal microscop (along Z-axis) of microcapsules produced by double emulsion


www.capsulae.com

Analysis

Thermal and mechanical characterizations: Dynamical mechanic analysis (DMA): • elastic properties, breakage force, release triggered by pressure (e.g. crushing)

Differential Scanning Calorimetry (DSC): • profiles, heat-triggered mechanisms (e.g. release during baking)

Powder properties:

Water content, water activity (aw) and water sorption isotherm: • control of biological and chemical reactions• limitation of water uptake and enhancement of shelf-life

Volumetric mass density (He pycnometry): • control of sedimentation or creaming of microparticles or microcapsules

Flowability (Carr index, Hausner’s ratio): • flowability improvement, decrease of friction phenomena, or fine powder formation

1. Objectives

2. Technologies

3. Analysis


Thermo-mechanicalproperties


Quantification

4. Conclusion

Uncoated (left) & coated (right) freeze-dried probiotic bacteria after

storage at high Aw value

Breakage of core / shell capsule containing oil


www.capsulae.com

Analysis

Microbiology (bacteria, yeast, fungi):

• Culture of micro organisms (immobilized vs free cells)• Cell concentration, viability and survival rates:

over the encapsulation process, in specific conditions (e.g. simulated gastric conditions)

• Stability studies (controlled temperature and humidity)

Quantification: active titration, analysis, release profiles

• Conductivity, pH• Chromatography / Spectrometry• Spectroscopy, NMR…

1. Objectives

2. Technologies

3. Analysis


Thermo-mechanicalproperties


Quantification

4. Conclusion

0

2

4

6

8

10

12

14

16

18

0 120 240 360 480 600 720 840 960 1080 1200

NaC

l con

cent

ratio

n (m

mol

/L)

Time (secondes)

WaterNaClStearic/palmitic acid blendCandelilla waxcarnauba wax

Immobilized cell culture (left) & cell enumeration (right)

Effect of material coating on the release of NaCl in solution

J. Agric. Food Chem. 2012, 60 (43), 10808-10814


www.capsulae.com

Conclusion

Factors to consider for selecting the appropriate technology

Active compound(s) / Core material

• Physico-chemical properties, physical state, size• Optimum concentration in the microparticles

Wall material / shell formulation

• Application(s): immobilization, protection, functionalization, release…• Stabilizing or barrier properties (O2, H2O, pH, T°C, shear,…)• Regulatory aspects: material grade, daily uptake (food/feed)…• Compatibility with core material• Release mechanism

Encapsulation process:

• Stability of core material during process• Encapsulation efficiency• Microcapsule morphology, particle size and distribution

Cost constraints, economic feasibility of large-scale production

1. Objectives

2. Technologies

3. Analysis

4. Conclusion

SelectionIndustrialization

Capsulae


www.capsulae.com

Conclusion

Encapsulation technologies: industrial scale

All the encapsulation technologies presented are fully available at lab, pilot and industrial scales.

Unit capacity could be up to 100’s of tons/year.

Costs study: equipment investment, materials cost, operating costs. Industrial production: internalization vs subcontracting

1. Objectives

2. Technologies

3. Analysis

4. Conclusion


Capsulae

0

0,2

0,4

0,6

0,8

1

1,2

0 1000 2000 3000 4000 5000

Pro

duct

ion

cost

s

Productivity

Emulsion / Stabilization

Dripping

Coating

Spray-dryingPrilling


www.capsulae.com

Conclusion

Capsulæ: company presentation & services Capsulæ is a French Private Research and Technology Organization providing key R&D input to corporate innovation projects.

Capsulæ develops for its clients throughout the industrial world customized solutions which facilitate and optimize the performance of ingredients and active compounds, via microencapsulation.

Capsulæ offers a full range of services, including the following:

• Design of innovative solutions and feasibility studies• Encapsulation problem solving • Scaling-up studies and pilot-scale evaluation• Small pilot-scale production• Know-how licensing and technology transfer• Support at the industrialization stage

“From 10’s of grams to 10’s of kilos”

1. Objectives

2. Technologies

3. Analysis

4. Conclusion


Capsulae

Visit us at capsulae.com

Encapsulation technologies A general overvie - Capsulae.pdf · Capsulæ / Encapsulation technologies - Capsulae 3 Introduction Encapsulation: definition and concepts Encapsulation

Documents