Applications

Many advanced medical and biological devices require microscale patterning of cells, proteins, and other biological materials. This article describes the use of piezoelectric ink jet processing in the fabrication of biosensors, cell-based assays, and other microscale medical devices. A microelectromechanical system-based piezoelectric transducer was used to develop uniform fluid flow through nozzles and to prepare well-defined microscale patterns of proteins, monofunctional acrylate ester, sinapinic acid, deoxyribonucleic acid (DNA), and DNA scaffolds on relevant substrates.

A photometric assay was developed to study the surface erosion of polymeric nanoparticles. The hydrolytic degradation of polyalkylcyanoacrylate particles was studied in different environments (NaOH, buffer, cell culture medium and serum). The influence of particle modification on the degradation rate was assessed. Particularly, the effect of polymer coating for particle targeting and fluorescence labelling was investigated. From the absorption data, a t 50% and t 100% can be calculated for fast degrading particles and obtained by an extrapolation in case of a slow degradation process.

Synthetic adhesives have largely displaced natural adhesives in the automotive, aerospace, biomedical, electronic, and marine equipment industries over the past century. We have demonstrated the thin film deposition of biological adhesives using piezoelectric inkjet technology. A MEMS based piezoelectric actuator was controlled to jet uniform fluid flow of the adhesive solution through the ink jet nozzles. Microscopic deposition of adhesives enables improved bonding for a range of advanced electronic and biomedical applications.

In this study, we have demonstrated the use of piezoelectric inkjet printing to fabricate microscale patterns of Vetbond® n-butyl cyanoacrylate tissue adhesive. Optical microscopy, atomic force microscopy, nanoindentation, and a cell viability assay were used to examine the structural, mechanical, and biological properties of microscale cyanoacrylate patterns. The ability to rapidly fabricate microscale patterns of medical and veterinary adhesives will enable reduced bond lines between tissues, improved tissue integrity, and reduced toxicity.

Exploiting crystal engineering and supramolecular synthon concepts, a series of new gelator salts based on primary ammonium dicarboxylate (PAD) salts of azobenzene-4,4′-dicarboxylic acid and primary alkyl amines have been synthesized and characterized by various physico-chemical techniques. Most of the salts were shown to form gels with various solvents. Interestingly, most of the gelator salts possessed rarely observed reverse-thermal gelation (gelation with the rise of temperature) ability of aromatic solvents which may be relevant in developing thermo-responsive materials.

An adhesive cement is prepared by coating an aluminosilicate glass ionomer with an acid polymerization inhibitor of pKa between 2-3.5, and then mixing the treated glass with cyanoacrylate monomer and water. The glass is treated by dissolving the acid, typically tartaric, tartronic, malic, maleic or mellitic acid in methanol and adding the glass powder to form a slurry, then evaporating the methanol.

The present invention relates to thickened cyanoacrylate compositions, such as those in gel or non-flowable forms. More particularly, the present invention relates to non-flowable cyanoacrylate compositions which can be packaged in a convenient pocket-sized applicator dispenser for use in spreading the cyanoacrylate compositions onto substrates.

New organogelator, N,N′-bis(3,4,5-tridodecyloxy)benzoylurea (1), gelled organic liquid such as alcohol, hydrocabons, ethyl acetate, salad oil, terpenes, and essential and perfume oil at low concentration of gelator. The terpene and perfume gels show good release of the volatile components for a long time.

It is accepted that terpenes are effective penetration enhancers to promote the passage of drugs or chemicals through the human skin barrier. However the physical and chemical changes of a pharmaceutical vehicle induced by the incorporation of terpenes have not been explored. Thus, this study examines the effects of three terpenes (linalool, cineole, limonene) on the rheology and chemical stability of an organogel composed of dibutyllauroylglutamide (GP1) and propylene glycol (PG).

Arjunolic acid, a triterpenoid, renewably resourced from Terminalia arjuna saw- dust, has the potential of being used as a structural molecular framework in supramolecular chemistry and nanoscience. The nanosized chiral triterpenoid on derivatization could immo- bilize varieties of organic solvents at low concentrations. The low-molecular-mass organic compounds self-assembled in organic media to form fibrous network structures having fibers of nano- to micrometer diameters. A dual-component supramolecular gelation has been demonstrated, exhibiting interesting thermochromic property.