LASER OPTOFLUIDICS IN FIGHTING MULTIPLE DRUG RESISTANCE

DOI: 10.2174/97816810849851170101

EISBN: 978-1-68108-498-5, 2017

ISBN: 978-1-68108-499-2

edited by MIHAIL LUCIAN PASCU in BENTHAM Scientific and published as E-Book on 20th July 2017.

The chapters of the book are written mainly by members of the Laser Spectroscopy Group from Laser Department and their collaborators. 18 authors of 40 are coming from eight countries outside Romania: Bulgaria, China, Germany, Iran, Kazakhstan, The Netherlands, Sweden, Turkey.

BRIEF BOOK DESCRIPTION

The book has an inciting title, „Laser Optofluidics in Fighting Multiple Drug Resistance” and treats a subject of high interest that is a challenge for biomedical specialists, chemists, physicists, public health experts and even outer space applicants: fighting multiple drug resistance acquired by bacteria and tumours in normal and/or extreme conditions.

The editor and the invited authors propose two action lines, each of them implying pluri-disciplinary experiments and data interpretation:

(i) exposure of selected non-antibiotic medicines at UV pulsed laser beams to modify their chemical structure and generate photoproducts with enhanced properties in fighting multiple drug resistance. Parent compounds do not have significant effects on bacteria or tumour tissues, but after being exposed to laser radiation in water solutions they generate photoproducts with individual or synergistic effects on biological targets. The book shows recent results in the action of exposed chlorpromazine and thioridazine on Gram-positive and Gram-negative bacteria and their antibacterial and antibiofilm enhanced activity. Complementary, a report on methotrexate exposed to continuous wave UV-Vis optical radiation emitted by lamps and then utilised on eye pseudotumours evidenced that the cocktail of photoproducts has in some cases anti-inflammatory effects higher than the parent compound. Another clinically used cytostatic, 5-Fluorouracil, exposed to UV pulsed nitrogen laser beams evidenced the same effects as methotrexate.

(ii) the „simple” identification of the obtained photoproducts is a complex problem since the photochemistry of the processes is quite complicated; consequently, many procedures are utilised with this purpose and results are shown in the book based on : laser induced fluorescence (LIF), mass spectrometry, thin layer chromatography, UV-Vis and FTIR absorption spectroscopy, microfluidics (surface tension, contact angles, wetting properties). They are correlated with rigorous description of micro-volumetric droplets as vectors to transport medicines to targets by applying microfluidics methods and procedures. Particular attention is devoted to description of the interaction – unresonant and resonant – between a laser beam and a single droplet which is of interest in biomedical applications since it allows to fast modify the content of a microdroplet and then to send parts of it on target.

In presenting results, the editor took care that the book provides interdisciplinary and multidisciplinary information about: laser systems used to modify pendant droplets and bulk solutions, properties of laser beams with emphasis on those essential in reported applications, behaviour of droplets containing medicines exposed to laser radiation in terrestrial gravity and hypergravity conditions, microspectroscopy specific methods to explore droplets’ content.

The hypergravity experiments and results are groundbreaking since they show that microdroplets of chlorpromazine water solutions have better wetting properties when exposed long time to laser beams compared to water at different gravity levels. In general, unexposed/exposed medicine droplets to laser have better ability to wet cotton or activated charcoal surfaces.

New results are shown about the way in which very small concentrations of photoproducts may be seized after exposure of compounds at laser beams, such as an antibiotic like vancomycin. The method is based on microfluidic approach which allows measurement of surface tension at the interface between a gas bubble and the laser exposed solution. It may be also interpreted in terms of cleaning procedure of water from pollutants found at very low concentrations.

The target readers of the book are medical doctors, physicists, optofluidics and microfluidics specialists, photochemists, biologists, laser spectroscopists as well as specialists in a broad area of domains ranging from delivery methods of medicines using different sorts of fabrics, to the use of multifunctional medicines in outer space missions, after passing hypergravity conditions. A particular target group is constituted by students experimenting in laser spectroscopy, biology, biomedicine, photochemistry, biophotonics and microfluidics since the book provides new and innovative information about behaviour of liquid drops, foams, emulsions and bubbles at interaction with laser radiation and possible applications of the results in mentioned fields.

The book is conceived not only as a coherent synthesis of new results, but also as a source of novel ideas, yet untreated, that are proposed to readers as working variants in future research. This approach would allow, among others, a fast and flexible reaction in the fight against naturally or accidentally occurring multi-resistant microorganisms and tumours, with fast enough results to allow a rapid deal with environment unexpected changes.

A particular interest is devoted to the use of laser spectroscopy and related methods to provide multifunctional drugs that may be applied for treatment of humans or for decontamination of modules during space flights, in the conditions in which confined small spaces are used in isolation regime for long time intervals, as happens in interplanetary missions.

Another subject of interest is the micro-lasers or micro-lasing droplets that emit in free space around them and may be used in a large area of biomedical and technological applications.