Browsing by Author "Paul, Willi"

Now showing 1 - 4 of 4
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    Blood compatibility studies of Swarna bhasma (gold bhasma), an Ayurvedic drug.
    (International journal of Ayurveda research, 2011)
    Swarna bhasma (gold bhasma) preparations are widely utilized as therapeutic agents. However, in vitro biological evaluations of bhasma preparations are needed along with the physicochemical characterization for present day standardization of metallic bhasma preparations to meet the criteria that supports its use. Therefore, an attempt has been made to evaluate the protein adsorption, blood compatibility and complement activation potential of two batches of Swarna bhasma preparation, along with its physicochemical characterization. The particle size, morphology, elemental analysis, and in vitro cytotoxicity were evaluated initially. Red blood cell hemolysis, aggregation studies with blood cells, protein adsorption, complement C3 adsorption, platelet activation and tight junction permeability in Caco-2 cell line were investigated. The Swarna bhasma preparations with a crystallite size of 28-35 nm did not induce any blood cell aggregation or protein adsorption. Activation potential of these preparations towards complement system or platelets was negligible. These particles were also non-cytotoxic. Swarna bhasma particles opened the tight junctions in Caco-2 cell experiments. The results suggest the application of Swarna bhasma preparations as a therapeutic agent in clinical medicine from the biological safety point of view.
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    Copper complexed polymer carriers for IgG adsorption
    (JOURNAL OF COLLOID AND INTERFACE SCIENCE, 2010)
    Cost effective adsorption matrix is recently, a much sought after alternative to the normal and expensive forms of matrices that are being used for the separation and purification of therapeutic molecules like immunoglobulins. A study therefore, has been focussed on developing copper complexed poly (vinyl alcohol) [PVA] and poly (styrene allyl alcohol) [PSA] gel beads for the separation of immunoglobulin G (IgG) from aqueous solutions. The copper-immobilized PVA and PSA gel beads were prepared, characterized and the copper content was estimated using EDX analysis. Further compatibility tests such as erythrocyte aggregation, lyses and cell counting were also investigated. An increase in the IgG adsorption capacities was achieved with the copper immobilized micro particles, when compared with the unmodified particles. (C) 2010 Elsevier Inc. All rights reserved.
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    Effect of calcium, zinc and magnesium on the attachment and spreading of osteoblast like cells onto ceramic matrices
    (JOURNAL OF MATERIALS SCIENCE-MATERIALS IN MEDICINE, 2007)
    Calcium phosphate ceramic has been widely used as bone substitute materials. Neumerours approaches have been investigated to develop tissue-engineered scaffold from hydroxyapatite because of its advantages like osteoconduction. We have developed porous ceramic matrices from nanoparticles of calcium phosphate containing zinc and magnesium. Mimicking the grain size of natural bone enhances the bone forming function of cells. Osteoblast-like MG63 cells were cultured on to these porous ceramic matrices. Cell adhesion and spreading onto these matrices were studied for 24 h and 5 days in vitro. It was observed that on calcium phosphate matrix, containing a combination of zinc and magnesium, the osteoblast adhesion and spreading was significant on 5th day. This appeared to be comparable to the hydroxyapatite control. This makes it a promising candidate as a bone tissue-engineering scaffold.
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    Tricalcium phosphate delayed release formulation for oral delivery of insulin: A proof-of-concept study
    (JOURNAL OF PHARMACEUTICAL SCIENCES, 2008)
    Several attempts have been made for delivering insulin orally utilizing several polymers with varying degrees of effectiveness. A major obstacle associated with polymeric delivery system for protein or polypeptide drugs is the poor retention of the structure and its biological activity of encapsulated proteins particularly for the unstable insulin. Calcium phosphate ceramic is considered highly compatible to protein or peptide drugs, particularly insulin. Therefore, an attempt has been made to load insulin in tricalcium phosphate (TCP) microspheres and coat with pH sensitive polymer of methacrylate derivative, and to study the stability and conformational variations of loaded insulin, and finally the biological activity of the formulation in diabetic rats. TCP microspheres were prepared by a standard procedure. Human insulin was loaded in to these porous microspheres by diffusion filling and coated with Eudragit S100. This was subjected to in vitro release studies in simulated fluids and the stability and conformational variations of the released insulin were studied using photon correlation spectroscopy and circular dichroism (CD). Biological activity of the formulation was studied on induced diabetic rats. Insulin released in the intestinal fluid (SIF) maintained the native conformation without showing any aggregation. A dose dependent reduction of blood glucose level (BGL) was achieved in streptozotocin induced diabetic Wistar rats, demonstrating its biological activity. It has been established from this preliminary study that insulin loaded in to TCP microspheres is highly compatible with no degradation or loss of biological activity of loaded insulin. The TCP microsphere based delayed release formulation of insulin has effected a decrease in elevated glucose level in induced diabetic rats, establishing its feasibility towards the development of a noninvasive delivery device. (C) 2007 Wiley-Liss, Inc. and the American Pharmacists Association.