Thermal Detection of Cardiac Biomarkers Heart-Fatty Acid Binding Protein and ST2 Using a Molecularly Imprinted Nanoparticle-Based Multiplex Sensor Platform.

This manuscript describes the production of molecularly imprinted polymer nanoparticles (nanoMIPs) for the cardiac biomarkers heart-fatty acid binding protein (H-FABP) and ST2 by solid-phase synthesis, and their use as synthetic antibodies in a multiplexed sensing platform. Analysis by surface plasmon resonance (SPR) shows that the affinity of the nanoMIPs is similar to that of commercially available antibodies. The particles are coated onto the surface of thermocouples and inserted into 3D-printed flow cells of different multiplexed designs. We demonstrate that it is possible to selectively detect both cardiac biomarkers within the physiologically relevant range. Furthermore, the developed sensor platform is the first example of a multiplex format of this thermal analysis technique which enables simultaneous measurements of two different compounds with minimal cross selectivity. The format where three thermocouples are positioned in parallel exhibits the highest sensitivity, which is explained by modeling the heat flow distribution within the flow cell. This design is used in further experiments and proof-of-application of the sensor platform is provided by measuring spiked fetal bovine serum samples. Because of the high selectivity, short measurement time, and low cost of this array format, it provides an interesting alternative to traditional immunoassays. The use of nanoMIPs enables a multimarker strategy, which has the potential to contribute to sustainable healthcare by improving the reliability of cardiac biomarker testing.

Temperature-Dependent Solubilization of the Hydrophobic Antiepileptic Drug Lamotrigine in Different Pluronic Micelles-A Spectroscopic, Heat Transfer Method, Small-Angle Neutron Scattering, Dynamic Light Scattering, and in Vitro Release Study.

Pluronics (tri-block copolymers) have a significant role in the pharmaceutical industry and are being used to enhance the solubility and delivery of hydrophobic drugs in different marketed formulations. However, instability and unsatisfactory drug-loading capacity are the major weak spots of these pluronic micelles. The present research work is designed to solve the existing issues by the solubilization study of hydrophobic drugs in different pluronic micelles at variable temperatures. The solubilization of the hydrophobic antiepileptic drug lamotrigine (LAM) in five different pluronic micelles viz. P84, P85, F127, F108, and F68 was studied at different temperatures, 37, 47, and 57 °C, using UV-visible spectroscopy. The solubilization of LAM in pluronic micelles increased with the increase in temperature. Small-angle neutron scattering (SANS) measurements were used to observe the morphological and structural changes taking place in pluronics by increasing the temperature. The SANS results showed the morphological changes of spherical P84 micelles to prolate ellipsoidal micelles at 57 °C due to remarkable increase in the aggregation number. This morphological conversion was further confirmed by the heat transfer method (HTM) and dynamic light scattering (DLS) measurements. DLS measurements confirmed that LAM-loaded micelles showed a greater hydrodynamic diameter (D h) compared to unloaded micelles, assuring LAM solubilization in the pluronic micelles. The rate of controlled release of LAM from five different pluronic micelles was accessed by using different kinetic models to evaluate the in vitro release profile. This is the first report in which HTM measurements are established for the analysis of morphological changes in the thermoresponsive pluronic micelles in real time. The present work corroborates how we can control the drug-loading capacity, morphological structure of the drug carrier, as well as drug release by simply changing the temperature of pluronic micellar media.

Heat-Transfer Method: A Thermal Analysis Technique for the Real-Time Monitoring of Staphylococcus aureus Growth in Buffered Solutions and Digestate Samples.

The identification and quantification of microorganisms in water samples are crucial to improve processes in organic waste treatment facilities. Most of the currently available tests are either labor intense or costly, and they do not allow determination of the dynamics within microbial communities in digestate samples. This study is the first report on the use of thermal analysis, specifically the heat transfer method (HTM), to monitor microbial load in aqueous systems and digestate samples. Staphylococcus aureus was used as a model organism, and different concentrations in water were measured by the HTM. It was demonstrated that there was a positive correlation between the thermal resistance and concentration of the bacterial cells. Subsequently, the influence of temperature on growth rates was studied and confirmed by plating experiments and scanning electron microscopy (SEM). These results showed the possibility to monitor the temperature-dependent growth of S. aureus using the HTM. To determine if this technique can be applied for studying complex matrices, digestate samples were collected from a number of sources and plated on nutrient agar plates. The bacterial cultures derived from single colonies were characterized and identified by sequencing of DNA regions for 16S rRNA. HTM measurements were performed in diluted or centrifuged digestate samples that were enriched with S. aureus. The results indicated that it is possible to evaluate microbial load even in samples containing other organic material. The thermal analysis method has the potential to provide a low-cost monitoring option, which is simple to use and provides real-time analysis, thus improving the existing monitoring procedures in organic waste treatment facilities.