PK Modeling of L-4-Boronophenylalanine and Development of Bayesian Predictive Platform for L-4-Boronophenylalanine PKs for Boron Neutron Capture Therapy.

L-4-[(10B)]Boronophenylalanine (BPA) is an amino acid analogue with a boron-10 moiety. It is most widely used as a boron carrier in boron neutron capture therapy. In this study, a Bayesian predictive platform of blood boron concentration based on a BPA pharmacokinetic (PK) model was developed. This platform is user-friendly and can predict the individual boron PK and optimal time window for boron neutron capture therapy in a simple way. The present study aimed to establish a PK model of L-4-boronophenylalanine and develop a Bayesian predictive platform for blood boron PKs for user-friendly estimation of boron concentration during neutron irradiation of neutron capture therapy. Whole blood boron concentrations from seven previous reports were graphically extracted and analyzed using the nonlinear mixed-effects modeling (NONMEM) approach. Model robustness was assessed using nonparametric bootstrap and visual predictive check approaches. The visual predictive check indicated that the final PK model is able to adequately predict observed concentrations. The Shiny package was used to input real-time blood boron concentration data, and during the following irradiation session blood boron was estimated with an acceptably short calculation time for the determination of irradiation time. Finally, a user-friendly Bayesian estimation platform for BPA PKs was developed to optimize individualized therapy for patients undergoing BNCT.

The simple and fast isolation of Escherichia coli O157:H7 using magnet nanoparticle embedded silica nanotube for the nucleic acid based detection.

In this study, we developed a simple and fast isolation tool of Escherichia coli O157:H7 (E. coli O157:H7) using a magnet nanoparticle embedded silica nanotube (MNSNT) for the detection of E. coli O157:H7 in the sample with nucleic acid based amplification. This method does not require chaotropic salt and sophisticated equipment to isolate bacteria. The E. coli O157:H7 in the sample was effectively bound to the hydrophilic surface of MNSNT in low pH binding buffer containing divalent ions and PEG without the need for expensive biological reagents such as antibodies. This E. coli O157:H7 bound MNSNT was simply isolated by a magnet, prior to adding an amplification mixture to the same micro tube without transferring the sample to another tube. Using this novel method, the detection sensitivities of E. coli O157:H7 (102 cfu/1 g of seed sprout and 102 cfu/5 mL of water) were 80% and 100%, respectively, whereas that was 0% using the commercial method.

The fabrication of protein nano arrays using 3-dimensional plastic nanopillar patterns.

A plastic nanopillar array was used as the basis for development of a cheap, spatially patterned immobilization method that was applied to nano biochips. A plastic nanopillar array (diameter: 500 nm, height: 1.2 microm) was fabricated using poly(urethane acrylate) (PUA) by simple and fast UV-curable soft lithography. Antibodies were immobilized on top of the nanopillar structure due to the 'lotus effect'; the aqueous solution containing proteins could only contact the top portion of the nanopillar array due to the hydrophobicity of the surface. This phenomenon was verified by atomic force microscopy and confocal microscopy. Optimal conditions were investigated to effectively generate a clear protein pattern on the nanopillar array. The immunoreaction capability of captured antibodies immobilized on the nano pattern was validated using various concentrations of complimentary antibodies.

Bacteria adsorption on hydrophilic surfaces for the sensitive detection of pathogenic bacteria using a single tube chamber system.

Here, we developed a simple and effective bacterial isolation method that can be directly used for the detection of pathogenic bacteria. This approach only requires a single plastic tube chamber that can performing serial processes such as cell gathering, cell lysis, nucleic acid amplification, and signaling without the need to transfer samples from one chamber to another. A TEOS (tetraethoxysilane) surface was selected for this application because of its superior performance in the amplification process as well as the ability of bacteria to adsorb to its surface, which is necessary for all processes to be performed in single chamber. The optimal aquatic buffer conditions for bacteria adsorption on the hydrophilic surface were determined to be 1% polyethylene glycerol (PEG) and 10 mM MgCl(2) in 100 mM phosphate at pH 4 for the gram negative bacteria, Escherichia coli O157:H7 (E. coli O157:H7) and 10 mM Na(2)SO(4) in 100 mM phosphate in 100 mM phosphate at pH 4 for the gram positive bacteria, Bacillus cereus (B. cereus). When these divalent cation and anion (MgSO(4)) containing acidic solutions were used, 40% of both bacteria adsorbed onto the hydrophilic surface at a loading rate of 2 mL/min after introduction of low concentrations of bacteria. This method was directly employed to detect E. coli O157:H7 in beef using a single plastic tube chamber that was partially filled with nickel micro beads coated with TEOS. In this system, E. coli O157:H7 were lysed by induction heating of the nickel micro beads. The extracted mRNA was readily amplified and detected by adding an isothermal amplification mixture (NASBA, nucleic acid sequence based amplification) containing a hair-loop type reporting probe with FAM and DABCYL. As a result, this highly sensitive sensing tool could detect very low concentrations of E. coli [10(0) CFU/1 g of beef].

Highly sensitive Escherichia coli O157:H7 detection in a large volume sample using a conical polymer tube chamber consisting of micro-glass beads.

In this study, we developed a method for the highly sensitive detection of viable pathogenic bacteria in a large volume sample by performing RNA concentration, amplification, and using fluorescently tagged capture probes in a single polymer chamber without transferring RNA samples from one chamber to another. Nucleic acids were extracted from Escherichia coli O157:H7 and loaded into glass micro-beads embedded in a conical polymer tube chamber. Nucleic acids were concentrated in the micro-tube in a low pH buffer (pH 5). The mRNA, which was adsorbed to the glass micro-beads, was amplified by Nucleic Acid Sequence Based Amplification in the same chamber at a relatively high pH (pH 8.9). The products amplified were measured using the hair-loop type detection probe with FAM and DABCYL, which was pre-mixed in the NASBA mater mixture. As a result, high sensitivity (100% for rain water and 60% for river water) with less than 10 viable E. coli O157:H7 in 100ml could be achieved within 4h using the simple method proposed in this study.