Carbohydrate Hydrogels with Stabilized Phage Particles for Bacterial Biosensing: Bacterium Diffusion Studies

Abstract

Bacteriophage particles have been reported as potentially useful in the development of diagnosis tools for pathogenic bacteria as they specifically recognize and lyse bacterial isolates thus confirming the presence of viable cells. One of the most representative microorganisms associated with health care services is the bacterium Pseudomonas aeruginosa, which alone is responsible for nearly 15% of all nosocomial infections. In this context, structural and functional stabilization of phage particles within biopolymeric hydrogels, aiming at producing cheap (chromogenic) bacterial biosensing devices, has been the goal of a previous research effort. For this, a detailed knowledge of the bacterial diffusion profile into the hydrogel core, where the phage particles lie, is of utmost importance. In the present research effort, the bacterial diffusion process into the biopolymeric hydrogel core was mathematically described and the theoretical simulations duly compared with experimental results, allowing determination of the effective diffusion coefficients of P. aeruginosa in the agar and calcium alginate hydrogels tested.

Biomimetic aqueous-core lipid nanoballoons integrating a multiple emulsion formulation: A suitable housing system for viable lytic bacteriophages

“…Additionally, imprisonment of a protein entity (such as the bacteriophage particles entertained in the present research effort) promotes a change in the thermodynamic conditions of the nanoenvironment surrounding each biomolecule due to the fact that the movements of (aqueous) solvent molecules in their microneighborhood become seriously reduced by the effect of being contained within the matrix's aqueous core, thereby leading to enhanced thermodynamic stability. The net result is an enhancement of the protein entity's rotational, translational and vibrational viscosity, promoting a more rigid three-dimensional architecture of the biomolecule with concomitant decrease of entropy and thus promoting its structural and functional stabilization [3][4][5][6]. The use of these multiple emulsion systems, provided the correct phage particles are used, e.g.…”

“…Phage particles possess a high potential for biopharmaceutical applications. However, as most proteins or enzymes, they are fragile, and therefore stabilization is required [3,4,6]. One possibility is to encapsulate these protein particles into nanometer-sized vesicles so as to protect them from deactivation by the immune system and dilution effects.…”

Structural and functional stabilization of bacteriophage particles within the aqueous core of a W/O/W multiple emulsion: A potential biotherapeutic system for the inhalational treatment of bacterial pneumonia

“…The increasing worldwide awareness related to the appearance of multiple bacterial resistance to conventional chemical antibiotics [1,2] has shed a renewed interest from the scientific community to bacteriophage (or phage) particles, with these inert (i.e., devoid of any metabolic machinery) entities being re-discovered as high-potential candidates for biopharmaceutical (antimicrobial) applications [3][4][5][6][7]. However, like most biological (macro)molecules, phage particles are intrinsically fragile and therefore their full structural and functional stabilization is mandatory [3,4,[8][9][10][11] prior to any use.…”

“…The increasing worldwide awareness related to the appearance of multiple bacterial resistance to conventional chemical antibiotics [1,2] has shed a renewed interest from the scientific community to bacteriophage (or phage) particles, with these inert (i.e., devoid of any metabolic machinery) entities being re-discovered as high-potential candidates for biopharmaceutical (antimicrobial) applications [3][4][5][6][7]. However, like most biological (macro)molecules, phage particles are intrinsically fragile and therefore their full structural and functional stabilization is mandatory [3,4,[8][9][10][11] prior to any use. Solubilization of these protein-like entities in the aqueous-core of lipid nanodroplets, protecting them from deactivation by the immune system, dilution effects, and from any chemical stress [12][13][14][15], will thus promote their structural and functional stabilization [3,4,9,10], a sine qua non condition for these particles to be used as (bio)medicines.…”

“…However, like most biological (macro)molecules, phage particles are intrinsically fragile and therefore their full structural and functional stabilization is mandatory [3,4,[8][9][10][11] prior to any use. Solubilization of these protein-like entities in the aqueous-core of lipid nanodroplets, protecting them from deactivation by the immune system, dilution effects, and from any chemical stress [12][13][14][15], will thus promote their structural and functional stabilization [3,4,9,10], a sine qua non condition for these particles to be used as (bio)medicines. Colloidal systems such as water-in-oil-in-water (W/O/W) multiple emulsions (MEs) are systems in which dispersions of small water droplets within larger oil droplets are themselves dispersed in a continuous (external) aqueous phase [8,10,[16][17][18][19][20][21][22].…”