There are over hundred papers published by users of our instruments and 43 papers published by us in the major international Journals as of August 1, 2022. They are organized in 12 applications. Each application note below contains references and web links to the relevant papers from this list. You can access these references by clicking on particular application.
There are also 39 newsletters presented as pdf files for variety of different dispersions and emulsions
- Bio-Sciences and Pharmaceuticals
- CMP slurries, content of large particles
- Cement, zeta potential titrations
- Zeta potential at extreme ionic strengths
- Zeta potential in porous bodies
- Dairy products, droplet size and fat content
- Emulsions and microemulsions
- Cosmetics, nano-particles contents
Acoustic spectroscopy is a very simple method for sizing of nanoparticles. There are many examples published in the papers that are listed below. There is only one input parameter characterizing particles required for calculating particle size distribution at this size range – density of particles. A big advantage of Acoustics over light-based methods is ability of characterizing broad particle size distributions, which include nano-size fractions. Our recent studies show that Acoustics could monitor presence of nanoparticles with precision of 1%. This is important for nano-ecology and nano-toxicology.
Electroacoustics offers very reliable and simple way of characterizing zeta potential of nano-size particles. It is simpler than for particles with micron size because there is no need in particle size correction.. Electroacoustic spectrometer measures basically Smoluchowski electrophoretic mobility. Zeta potential probe can monitor presence of small amounts of large sedimenting particles in opaque dispersions of nano-particles
Bell, N., Cesarano, J., Voight, J.A., Lockwood, S.J. and Dimos D.B. “Colloidal processing of chemically prepared zinc oxide varistors. Part 1. Milling and dispersion of powder“, J. Mat. Res., 19, 5, 1333-1340 (2004)
Bell, N. and Rodriguez, M.A. “Dispersion properties of an alumina nanopowder using molecular, polyelectrolyte, and stericstabilization”, J. of Nanoscience and Nanotechnology, 4, 3, 283-290 (2004)
Sun, Y.-P., Li, X., Cao, J., Zhang, W. and Wang.H.P. “Characterization of zero-valent iron nano-particles”, Adv. in Colloid and Interface Sci., 120, 47-56 (2006)
Gaydardzhiev, S. and Ay,P. “Evaluation of dispersant efficiency for aqueous alumina slurries by concurrent techniques”, J. of Dispersion Science and Technology, 27, 413-417 (2006)
Wilhelm, P., Stephan, D. “On-line tracking of the coating of nanoscaled silica with titania nanoparticles via zeta-potential measurements”, JCIS, 293, 88-92 (2006)
Sun, Y.P., Li, X.Q., Zhang, W.X., Wang, H.P. “A method for the preparation of stable dispersion of zero-valent iron nano-particles”, Colloids and surfaces, 308, 60-66 (2007)
Mende, S. “Representarive on-line measurement of comminution results for nanogriding in stirred media mill”, NETCH, doctoral thesis
Stenger, F. Mende, S., Schwedes, J. and Peukert, W. “Nanomilling in stirred media mills”, Chemical Engineering Science, 60, 4557-4565 (2005)
Dukhin, A. S. “Observation of sol-gel transition for carbon nanotubes using electroacoustics: Colloid vibration current versus streaming vibration current.” JCIS, vol.310, 1, 270-280 (2007)
Comba, S. and Sethi, R. “Stabilization of highly concentrated suspersions of iron nanoparticles using shear-thinning gels of xanthan gum“, Water Research, 43, 15, 3717-3726 (2009)
Bio-Sciences and Pharmaceuticals
There are several developed applications with results published in the papers presented below. This includes:
- characterization of electric properties of chromatographic resins for proper control of their interactions with proteins
- particle size and evolution of micelles
- particle size of cells
- electric charges (valency) of proteins
- proteins adsorption.
Acoustics can characterize pharmaceutical emulsions and microemulsions with no dilution. Dilution is critical for such systems because it affect equilibrium there and can change droplet size distribution.
Acoustic measurement at a single frequency and single gap is useful for very fast monitoring kinetics of dissolving and crystallization. It offers several measurements per second.
Mueller, E. and Faude, A. “Investigation of salt properties with electroacoustic measurements and their effect on dynamic binding capacity in hydrophobic interaction chromatography”, J. of Chromatography A., vol. 1177, issue 2, 215-225 (2008)
Mueller, E. and Mann C. “Resin characterization by electroacoustic measurements”, J. of Chromatography A., vol. 1144, issue 1, 30-39 (2007)
Rezwan, K., Meier, L.P., Rezwan, M., Voros, J., Textor, M. and Gauckler, L.J. “Bovine cerum albumin adsorption onto colloidal Al2O3 particles. A new model based on zeta potential and UV-Vis Measurements”, Langmuir, (2005)
Rezwan, K., Meier, L.P., and Gauckler, L.J. “Lysozyme and bovine cerum albumin adsorption on uncoated silica and ALOOH-coated silica particles: the influence of positively and negatively charged oxide surface coatings”, Biomaterials, 26, 4351-4357 (2005)
Bonacucina, G., Misici-Falzi, M., Cespi, M., Palmieri, G.F. “Characterization of micellar systems by the use of Acoustic spectroscopy”, J. of Pharmaceutical Sciences, 1-11 (2007)
Dukhin, A. S., Goetz, P.J. and Theo G.M. van de Ven, “Ultrasonic characterization of proteins and blood cells”, Colloids and Surfaces B, 52, 121-126 (2006)
Acoustics can characterize particle size and zeta potential in ceramic slurries with no dilution. There are several papers published on this subject.
There is also possibility to characterize mixtures of different oxides, such as alumina and zirconia, see Chapter 8 in the book by Dukhin and Goetz. This can answer question regarding aggregation between particles of different nature.
Takeda, S., Harano, H., Tari, I. “Particle size characterization of highly concentrated alumina slurries by ultrasonic attenuation spectroscopy”, in Improved Ceramics through New Measurements, Processing and Standards, Ceramic Transactions, vol. 133, 59-63 (2002)
Takeda, S., Suenaga, H. and Tari, I. “Particle size characterization of highly concentrated barium titanate slurries by ultrasonic attenuation spectroscopy”, in Improved Ceramics through New Measurements, Processing and Standards, Ceramic Transactions, vol. 133, 53-59 (2002)
Takeda, Shin-ichi, and Goetz, P.J. “Dispersed/flocculated size characterization of alumina particles in highly concentrated slurries by ultrasonic attenuation spectroscopy”, Colloids and Surfaces, 143, 35-39 (1998)
Dukhin, A.S. and Goetz, P.J. “Characterization of Concentrated Dispersions with Several Dispersed Phases by means of Acoustic Spectroscopy”, Langmuir, 16, 20, 7597-7604 (2000)
There are two papers published on subject of applicability of ultrasound for characterizing CMP slurries, see below. So, there are also 2 newsletters, # 1 and # 13 on the same subject.
Acoustics provides accurate particle size that agrees well with independent data. It can monitor presence of 1% large particles on the background of small nanoparticles.
Electroacoustics yields very precise value of zeta potential
These measurements can be done with no dilution, which opens possibility for continuous on-line control of the slurry properties. However, calculation of the particle size and zeta potential requires information on the volume fraction. This parameter must be independently measured.
1.Dukhin, A.S., Fluck, D., Goetz, P.J., Shilov, V.N. and Dukhin, S.S. “Characterization of fractal particles using Acoustics, Electroacoustics, Light Scattering, Image analysis and Conductivity”, Langmuir, 23, 10, pp.5338-5351 (2007)
2.Dukhin, A.S. and Goetz, P.J “Characterization of Chemical Polishing Materials (monomodal and bimodal) by means of Acoustic Spectroscopy “, Colloids and Surfaces, 158, 343-354 (1999)
Acoustics and Electroacoustics can monitor effects of the plasticizer on the properties of the cement slurry, as proved in the papers listed below. With no dilution.
Elimination of dilution is critical for accurate measurement of the cement zeta potential. Dilution affects cement slurry strongly. Zeta potential probe offers zeta potential measurement with precision of 0.1 mV.
Hackley, A.V., Lum, Lin-Sien, Ferraris, C.F. “Acoustic sensing of Hydrating Cement Suspensions: An explanatory study”, NIST Technical Note 1492, (2007)
Plank, J. and Hirch, C. “Impact of zeta potential of early cement hydration phases on superplasticizer adsorption“, Cement and Concrete Research, (2007)
Plank, J. and Sachsenhauser, B. “Impact of molecular structure on zeta potential and adsorbed conformation of a-allyl-w-methoxypolyethylene glycol-maleic anhydride superplasticizers“, J. of Advanced Concrete Technology, 4, 2, 233-239 (2006)
Plank, J. and Gretz, M. “Study on the interaction between anionic and cationic latex particles and Portland cement“, Colloids and Surfaces, 330, 227-233 (2008)
Plank, J. and Winter, Ch. “Competitive adsorption between superplasticizer and retarder molecules on mineral binder surface“, Cement and Concrete Research, 38, 599-605 (2008)
Applications of Acoustics and Electroacoustics can characterize mineral dispersions, as described in the papers listed below. Titration option of the DTI instruments is suitable for determining optimum dose of surfactant for stabilizing clay and mineral dispersions.
Guerin, M. Seaman, J.C., Lehmann, C., and Jurgenson, A. “Acoustic and electroacoustic characterization of variable charge mineral suspensions“, Clays and Clay Minerals, vol. 52, 2, 158-
Guerin, M. and Seaman, J.C. “Characterizing clay mineral suspensions using acoustic and electroacoustic spectroscopy“, Clays and Clay Minerals, 52, 2, 145-157 (2004)
Dukhin, A.S., Goetz, P.J. and Truesdail, S.T. ” Surfactant titration of kaolin slurries using zeta potential probe”, Langmuir, 17, 964-968 (2001)
There are several experimental studies of the properties of concentrated oxides dispersions (rutile, zirconia, alumina, zinc oxide, etc) presented in the book by Dukhin, A.S. and Goetz, J.P. “Characterization of Liquids, Nano- and Microparticulates, and Porous Bodies using Ultrasound”, Edition 3, Elsevier, 571 pages, 765 references, (2017). .
Zeta potential at extreme ionic strengths
Electroacoustics works at the extremely high ionic strength above 1 M, as well as for non-polar liquids with conductivity below 10-10 S/m.
This method yields not only zeta potential at these extreme conditions, but also electric surface charge and even size of ions in non-polar liquids.
Tassel van J., Randall, C.A. “Surface chemistry and surface charge formation for an alumina powder in ethanol with addition of HCl and KOH“, JCIS, 241, 302-316 (2001)
Dukhin, A.S., Dukhin S.S. and Goetz, P.J. “Electrokinetics at high ionic strength and hypothesis of the Double Layer with Zero Surface Charge“, Langmuir, 21 (22) pp.9990-9997 (2005)
Dukhin, A. S. and Goetz, P.J. “How non-ionic “electrically neutral” surfactants enhance electrical conductivity and ion stability in non-polar liquids“, J. of Electroanalytical Chemistry, 588, 44-50 (2006)
Zeta potential in porous bodies.
Propagation of ultrasound through a porous body creates motion of liquid inside of the pores relative to the solid matrix. This, in turn, causes relative motion of ions that are located in the diffuse layer and on the pore surfaces. Such motion shows us as an electric current. This current is similar to the Streaming Current, with the difference that it oscillates in time. That is why it’s name is Streaming Vibration Current. There are papers already published reporting experimental observation of this effect.
This effect can be used for very fast and simple measuring electric surface properties of porous bodies.
Dukhin, A. S. “Observation of sol-gel transition for carbon nanotubes using electroacoustics: Colloid vibration current versus streaming vibration current“. JCIS, vol.310, 1, 270-280 (2007)
Mueller, E. and Mann C. Resin characterization by electroacoustic measurements“, J. of Chromatography A., vol. 1144, issue 1, 30-39 (2007)
Williams, M. “ “An Electrokinetic Transducer“, The review of scientific instruments, 19, 10, 640-646 (1948)
Dukhin, A.S., Goetz, P.J., Thommes, M. “The seismoelectric effect: A non-isochoric streaming current: 1. Experiment“, JCIS, 2010
Dukhin, A.S. and Shilov, V.N. “The seismoelectric effect: A non-isochoric streaming current: 2. Theory and its experimental verification” JCIS, 2010
Detail study presented in the paper listed below indicates that Acoustics yields a proper Particle size distribution in various dairy products. With no dilution.
In addition, Acoustics yields information for calculating fat content.
Dukhin, A.S., Goetz, P.J. and Travers, B. “Use of Ultrasound for Characterizing Dairy Products“, J.Dairy Science, 88, 4, pp. 1-15 (2005)
Emulsions and microemulsions
Acoustics makes possible measurement of the droplets size distribution in the emulsion and microemulsion with no dilution, which is critical for these systems. Papers presented below indicate very good agreement between this method and independent data.
Combination of Acoustics and Electroacoustics could reveal peculiar mechanisms controlling emulsion stability, such as ion exchange in water-in-oil emulsion, see Ref. 4.
Magual, A., Horvath-Szabo G., Masliyah, J.H. “Acoustic and electroacoustic spectroscopy of water-in-diluted bitumen emulsions“, Langmuir, 21, 8649-8657 (2005)
Dukhin, A.S. and Goetz, P.J. “Evolution of water-in-oil emulsion controlled by droplet-bulk ion exchange: acoustic, electroacoustic, conductivity and image analysis“, Colloids and Surfaces, A, 253, 51-64 (2005)
Wines, T.H., Dukhin A.S. and Somasundaran, P. “Acoustic spectroscopy for characterizing heptane/water/AOT reverse microemulsion“, JCIS, 216, 303-308 (1999)
Dukhin, A.S., Goetz, P.J. and Hamlet, C.W. “Acoustic Spectroscopy for Concentrated Polydisperse Colloids with Low Density Contrast“, Langmuir, 12, 21, 4998-5004 (1996)
Acoustics provides opportunity for characterizing content of nanoparticles in cosmetic dispersions with broad Particle size distributions. Precision is about 1% of the total solids content.
Dukhin, A.S., Goetz, P.J., Xiaohua Fang, Somasundaran, P. “Monitoring nanoparticles in the presence of larger particles in liquids using acoustics and electron microscopy“, JCIS, 342, 1, pp.18-25 (2010)