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Apeldoorn, Netherlands

Vollenbroek J.,FrieslandCampina Research | Hebbink G.A.,DMV Fonterra Excipients GmbH and Co KG | Ziffels S.,University of Kiel | Steckel H.,University of Kiel
International Journal of Pharmaceutics | Year: 2010

α-Lactose monohydrate is widely used as an excipient in dry powder inhalers, and plays a very important role in the efficiency of the drug delivery. Due to the processing, low levels of amorphous lactose could be present in the blends. Varying amounts could have a strong effect on the efficiency of drug delivery of the powder blends. Therefore, the accurate measurement of low levels of amorphous lactose content is very important. A new method was developed to measure the amorphous content, based on dynamic vapour sorption (DVS). In contrast to the traditional re-crystallization approach of amorphous lactose, the new method is based on moisture sorption isotherms. Moisture sorption isotherms of blends of crystalline α-lactose and freeze-dried or spray-dried amorphous lactose were measured. By fitting the data with a Brunauer, Emmett, and Teller (BET) isotherm, a linear correlation was found between measured and actual amorphous content for the whole range of 0.1-100%. Differences between freeze-dried and spray-dried lactose, due to different molecular arrangements, could be removed by a preconditioning the samples at 35% RH prior to the isotherm measurement. It was shown that accurate determination of very low concentrations of amorphous lactose content is possible using moisture sorption isotherm analyses. © 2010 Elsevier B.V.

Albrecht S.,Wageningen University | Schols H.A.,Wageningen University | Van Den Heuvel E.G.H.M.,FrieslandCampina Research | Voragen A.G.J.,Wageningen University | Gruppen H.,Wageningen University
Carbohydrate Research | Year: 2011

The characterization of oligosaccharides in the feces of breast-fed babies is a valuable tool for monitoring the gastrointestinal fate of human milk oligosaccharides (HMOs). In the present study we monitored fecal oligosaccharide profiles together with the HMO-profiles of the respective breast milks up to six months postpartum, by means of capillary electrophoresis-laser induced fluorescence detection and mass spectrometry. Eleven mother/child pairs were included. Mother's secretor- and Lewis-type included all combinations [Le(a-b+), Le(a+b-), Le(a-b-)]. The fecal HMO-profiles in the first few months of life are either predominantly composed of neutral or acidic HMOs and are possibly effected by the HMO-fingerprint in the respective breast milk. Independent of the initial presence of acidic or neutral fecal HMOs, a gradual change to blood-group specific oligosaccharides was observed. Their presence pointed to a gastrointestinal degradation of the feeding-related HMOs, followed by conjugation with blood group specific antigenic determinants present in the gastrointestinal mucus layer. Eleven of these 'hybrid'-oligosaccharides were annotated in this study. When solid food was introduced, no HMOs and their degradation- and metabolization products were recovered in the fecal samples. © 2011 Elsevier Ltd. All rights reserved.

Silpe J.E.,University of Michigan | Silpe J.E.,Princeton University | Nunes J.K.,Princeton University | Poortinga A.T.,FrieslandCampina Research | Stone H.A.,Princeton University
Langmuir | Year: 2013

We report the preparation of antibubbles by microfluidic methods. More specifically, we demonstrate a two-step approach, wherein a monodisperse water-in-oil-in-water (W/O/W) emulsion of core-shell construction is first generated via microfluidics and freeze-dried thereafter to yield, upon subsequent reconstitution, an aqueous dispersion of antibubbles. Stable antibubbles are attained by stabilization of the air-water interfaces through a combination of adsorbed particles and polymeric surfactant. The antibubbles strongly resemble the double emulsion templates from which they were formed. When triggered to release, antibubbles show complete release of their cores within about 100 ms. © 2013 American Chemical Society.

Poortinga A.T.,FrieslandCampina Research
Langmuir | Year: 2011

Antibubbles, which are liquid droplets surrounded by a thin shell of gas in a liquid phase, have several promising applications, among which is encapsulation. A major hurdle toward these applications has hitherto been the inherent instability of antibubbles, leading to lifetimes of at most minutes. Here we show the production of antibubbles with a lifetime of at least tens of hours, with their stability stemming from the adsorption of colloidal particles at gas-water interfaces. Antibubbles were produced by coating aqueous droplets with hydrophobic colloidal particles, gelling the droplets, and then dropping them into an aqueous colloidal suspension. This resulted in the formation of antibubbles with a long lifetime, also after the melting of the gel. © 2011 American Chemical Society.

Albrecht S.,Wageningen University | Schols H.A.,Wageningen University | Van Den Heuvel E.G.H.M.,FrieslandCampina Research | Voragen A.G.J.,Wageningen University | Gruppen H.,Wageningen University
Electrophoresis | Year: 2010

Mixtures of the complex human milk oligosaccharides (HMOs) are difficult to analyze and gastrointestinal bioconversion products of HMOs may complicate analysis even more. Their analysis, therefore, requires the combination of a sensitive and high-resolution separation technique with a mass identification tool. This study introduces for the first time the hyphenation of CE with an electrospray mass spectrometer, capable to perform multiple MS analysis (ESI-MSn) for the separation and characterization of HMOs in breast milk and feces of breast-fed babies. LIF was used for on- and off-line detections. From the overall 47 peaks detected in off-line CE-LIF electropherograms, 21 peaks could be unambiguously and 11 peaks could be tentatively assigned. The detailed structural characterization of a novel lacto-N-neo-tetraose isomer and a novel lacto-Nfucopentaose isomer was established in baby feces and pointed to gastrointestinal hydrolysis of higher-Mw HMOs. CE-LIF-ESI-MSn presents, therefore, a useful tool which contributes to an advanced understanding on the fate of individual HMOs during their gastrointestinal passage. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA.

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