Quantification of Microcapsules Deposited in Cotton Fabrics before and after Abrasion Using Fluorescence Microscopy

Abstract

Perfume microcapsules for laundry applications are extensively used in home and consumer care products. Capsules have to bind into the fabric during washing and survive the rinsing and drying steps until the desired moment of rupture, usually when in contact with the skin. In order to assess the performance of the microcapsules in the different steps, quantification methods are required. It is reported here the first methodology, using fluorescence microscopy, whereby the number and size of fluorescent microcapsules is individually determined in large fabric areas using image analysis. The performance of fluorescent melamine-formaldehyde perfume microcapsules of two different sizes under abrasion is studied using smooth and rough surfaces, under dry and wet conditions. Survival profiles are obtained with the number of abrasion passes, allowing for characterizing the performance of microcapsules under different conditions. In addition to quantification, fluorescence and optical microscopy allow for identifying where are the capsules deposited in the fabric, as well as which are the safest zones that allow microcapsules to survive extensive abrasion.

The Fabrication of Fragrance Microcapsules and Their Sustained and Broken Release Behavior

“…Moreover, the spectral characteristics of core materials can also be utilized to analyze their release properties. For example, Ruben et al [18] observed the crushing and residual property of prepared fluorescent dye microcapsules in finished fabric with a fluorescence microscope, and Bezerra et al [19] evaluated the controlled-release mechanism of citronella oil microcapsules in different substrates with an attenuated total reflection FTIR spectrometer.…”

Microencapsulation byin situPolymerization of Amino Resins

“…21 Controlled release can furthermore take place continuously The release profile of MCs is generally determined by dispersing of the particles in a solution and by measuring the evolution of the solute concentration over time. The release kinetics can be determined by a range of techniques adapted to the core content, such as spectroscopic techniques (UV-vis, 141 NMR, FTIR spectroscopic methods), microscopy (fluorescence), 142,143 chromatography (GC, 114,144 HPLC 145 ), sensors (e-nose 146 ) and TGA. Indirect measurements can also be performed by measuring the effect of the released core materials (e.g., cytotoxicity) 147 .…”

Advanced Eco-Friendly Formulations of Guar Biopolymer-Based Textile Conditioners

“…The amphiphilic molecules used in these conditioners are double-chain surfactants that self-assemble in vesicles [ 10 , 11 , 12 , 13 ]. The vesicles have a dual role: they provide long-term stability and transport active ingredients such as oils [ 14 ] and fragrance capsules [ 15 , 16 ] onto the fibers. Throughout the history of softeners, surfactants have been replaced by more effective and less toxic ones [ 8 ].…”