Technology for Long Last Senses

Assoc. Prof. Ubonthip Nimmannit, Ph.D.April 2nd, 2010

National Nanotechnology CenterNSTDA Pathumthani, Thailand

Fragrances

• Topnote

• Middle note

• Lasting note (Base note)

Topnote

• First impression

• High volatility, coefficients ranging 1-14

• No residual scent after 2 h

– Citrus, fruity, green note– Ginger, galanga, cardamom

Middle note

• Establishing the whole fragrance

• Medium volatility, coefficients ranging 15-60

• Last for 2-6 h

– Jasmine, rose, aldehyde, spicy note– Tuberose, coriander

Lasting note (Basic note or Fixer)

• Low volatile fixatives, coefficients ranging 61-100

• Last for more than 6 h– Oakmoss, woody note, animal note, civet

absolute, myrrh, velvety balsamic scent

Basic note/ Fixation– Musk ambrette– Ambergris extract– Ethyl vanillin/ vanillin– Methyl nonyl acetaldehyde– Fixateur 404

Persistence of Perfumes• Coefficient: ↑ nature of evaporation

↓ value of the threshold concentration

Volatility

• Odor intensity• Threshold value• Odor tonality

Stability of Fragrance

• Change of odor

• Change of color

Stability factors

• Oxygen

• Light

• Temperature

• Humidity

• pH of product

Microcapsules

• Small particles (1-100 μm)

• Active agent surrounded by polymeric membrane

• Protect from oxidation (by heat, light, humidity, exposure to other substances)

• Prevent evaporation

• Control release rate

Microcapsules

• Released by– Mechanical– Temperature– Diffusion– pH– Biodegradation– Dissolution

Techniques of encapsulation (Micro/ Nano)

• Phase separation techniques

• Interfacial polymerization techniques

• Mechanical techniques

Phase separation techniques

• Aqueous phase separation– Simple coacervation– Complex coacervation

• Nonaqueous phase separation– Non solvent addition– Temperature reduction

Complex coacervation

Positive charge polymer-negative charge polymer

Colloidal rich phase + equilibrium liquid

Microcapsules

Nanocapsules

dry

stirred

Phase separation

Interfacial Polymerization Technique

Monomer A + Monomer B

(Hydrophobic liquid) (Hydrophilic liquid)

Emulsifying

Polymer AB

Microcapsules + by product

Stirring

Mechanical Techniques

• Spray dry

• Atomization

• etc.

Selection of the technique and shell material

– Application of products– Physical and chemical stability– Concentration– Desire particle size– Release mechanism– Manufacturing cost

Microencapsulation process of limonene by interfacial polymerization.

Rodrigues, et al., Ind. Eng. Chem. Res. 2008, 47, 4142–4147

Oil phase (HMDI) + Aqueous phase 1 (PVA)

Formation of oil/water emulsion

Urethane formation

Aqueous phase 2 (PEG 400, DBTDL)

Urea formation

Aqueous phase 3 (EDA)

Urea formation

Aqueous phase 4 (HYD)

Separation/Washing

Polymerization and shell formation

Optical microscopy of microcapsules solution. Magnification: (a) 20x (b) 100x.

Textile Impregnated with Microcapsules Characterization. SEM Analysis

Rodrigues, et al., Ind. Eng. Chem. Res. 2008, 47, 4142–4147

Macrocapsules

• Diameter over 1000 mm

show a different porosity distribution,

T. Gum ํ et al. / Desalination 245 (2009) 769–775

Polysulfone capsules containing different vanillin concentrations.

Polymeric microspheres

• Fragrance incorporated in the polymer– Controlled by

• Initial loading of fragrance• Ability of fragrance to diffuse through polymeric

barrier

– Driving force• Interaction between fragrance molecule and

polymer matrix• Vapor pressure of fragrance

SEMandTEMimages of spheres obtained with the starting polymer concentrations of (a) 2000–16,000 ppm, (b) 18,000ppmand (c) 24,000–28,000 ppm.

(a) SEM, (b) TEM and (c) AFM images of menthol-encapsulated polymeric nanoparticle suspension (polymer blend : EC, HPMC, PV(OH)

A. Sansukcharearnpon et al. / Int J Pharm xxx (2010) xxx–xxx

Multiarm star-block copolymer• Multiarm star-block copolymer compared to

dendrimer– Less complex synthesis– Less time consuming– Lower cost

Limitation– Lower loading capacity than dendrimer

Multiarm star-block copolymer

Amphiphilic multiarm star-block copolymers with a hydrophilic inner and hydrophobic outer shell (top) and with a hydrophobic inner and hydrophilic outer shell (bottom).

Ternat et al., Macromolecules, Vol. 41, No. 19, 2008

Hydrophilic arms

Hydrophobic armsHyperbranched core structure

Multiarm star-block copolymer

Average structures of the Boltorn H40 core and amphiphilic multiarm star-block copolymers H40-(PnBuMA)p-b-(PPEGMA)q and H40-(PCL)p-b-(PAA)q.

Ternat et al., Macromolecules, Vol. 41, No. 19, 2008

Comparison of the evaporation rates of benzyl acetate from an aqueous solution (containing 5% of ethanol) in the presence and absence of amphiphilic multiarm star-block copolymer H40-(PCL)24-b-(PAA)82.

Multiarm star-block copolymer

Benzyl acetate

Benzyl acetate/ H40-(PCL)24-b-(PAA)82

Alginate complex capsules containing eucalyptus oil

• Interfacial insolubilization reaction

• Release by crashing the capsule between fingers

• Closed capsule wall

• Optimum condition– Concentration of alginate– Concentration of calcium salt– Cross-linking time

Microphotographs of alginate complex capsules before (a) and after (b) the hardening process (/80).

The capsuleswerepr eparedatconcentrati

onsof1 .5 %sodium alginate and1 .0 %c

alciumchloride, and t - he cross linking time

m mmm20

C.P. Chang, T. Dobashi / Colloids and Surfaces B: Biointerfaces 32 (2003) 257/262

Time courses of oil release from capsules at incubation process for the samples prepared at various conditions: At different concentrations of sodium alginate at constant calcium chloride concentration of 1 w/v% at cross-linking time of 20min. The symbols (circle), (triangle), (square) and (diamond) denote concentrations of sodium alginate of 0.25, 0.50, 1.0 and 2.0%, respectively.

Light induced controlled release of fragrances

Alkyl phenyl ketones serve as delivery systems for fragrance molecules upon exposure to natural sunlight

Preparation of alginate nanocapsules containing turmeric oil

Sodium alginate crosslink with calcium chloride

alginate nanocapsule

Lertsutthiwong P., Noomun K., Jongaroonngamsang N., Rojsitthisak P., Nimmannit U. 2008. Preparation of alginate nanocapsules containing turmeric oil. Carbohydrate Polymers. 74. 209–214.

Morphology and size of turmeric oil-loaded alginate nanocapsules

TEM characterization of nanocapsules, indicating an average size of about 95 nm.

Thank you