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Enzymatic luminescent systems are a promising tool for rapid detection of heavy metals ions for water quality assessment. Nevertheless, their widespread use is limited by the lack of test procedure automation and available sensitive handheld luminometers. Herein we describe integration of disposable microfluidic chips for bioluminescent enzyme-inhibition based assay with a handheld luminometer, which detection system is based on a thermally stabilized silicon photomultiplier (SiPM). Microfluidic chips were made of poly(methyl methacrylate) by micro-milling method and sealed using a solvent bonding technique. The composition of the bioluminescent system in microfluidic chip was optimized to achieve higher luminescence intensity and storage time. Results indicate that developed device provided comparable sensitivity with bench-scale PMT-based commercial luminometers. Limit of detection for copper (II) sulfate reached 2.5 mg/L for developed biosensor. Hereby we proved the concept of handheld enzymatic optical biosensors with disposable chips for bioassay. The proposed biosensor can be used as an early warning field-deployable system for rapid detection of heavy metals salts and other toxic chemicals, which affect bioluminescent signal of enzymatic reaction.

Key words: bacterial hiciferasc biotest, foreign wmpcnmds, energy of electron excited states level. rdox ptential, reducing of bioluminescent intensity, induction perid, time of nt:txiniurn light intensity. Kudryasheva N.S., Kratasyuk V.A., Etelobrov.P.1. Institute of Riophysics, Russian Academy of Sciences Siberian Branch, Krasnoyarsk, 660036, Russia ABSTRACT The physical-chemical regularities of aromatic cumpunds' effects i~i luciferase toxicity biotesting have. been studied. The structures and physical-chemical characterirtics of the toxicants and of the biduminescent emitter w a e takkcn into account. 'I he inhibrtiox! ccninants of bioluminescence intcnsiq (1) were calculated and interpreted !kom the vievcpcrint of the energy (dwtrcxi) transftz 293 1 Copyright 0 1994 by Marcel Dekker, Inc.Downloaded by [Columbia University] at 10:47 03 February 2015 2932 KUDRYASHEVA, KRATASYUK, AND BELOBROV prt~csses The induction penod (P) and the rncmse d fhr: f7mc of the rriavlnium light intensity (tb,) which take place iv the quinones' presence, have beer; shown to deal wixh hydrogen trandicr processes. '1 he vah:.: of I, P and t, have been shown to be cormericd with a size of the qumoncs' aromatic and aliphatic parts. P-?~? d t,-dc.rc.,ndeni.ies UR quhorte' s ledox pterxtial have been demonstrated. Bioluminescent (BL) organismi; and their luciferases tqxciahly.are very sendti--% to fareign toxic cornpomds. This sen'c'i the basis r : f toxlsity hiotests . ihe effect of compounds' mixtures OR fie H L s y s t m is ari inregral characteristic. It depnds in a complex way on the nature d the constituents, marked by the tx:rtairr physicalchemical parameters. 1 The airii of the prcsent studies is to reveal the :rzuianties in thc action of thc crganjc cornpounds on bacterial HI, qste.rrr :r? ~i t m , wrh their phyQca1-chemical characteri.itics taken into accotint studying of !fiest* relations would hdy to elucidate the 1:iechaninrt nt toxicants action arid predict the results of BL biorestine, 4$ the toxreants of a known stmct~xi-e L It is known that the main characteristics of the c m p u n d s ' structure are nature, energy and relative position of the energetic levels of their clecrron excited mites. By the previous work we have proposed the chemical excitation mechanism of bioluminescent emitter. 1 t deals witti the stage the excitation is formed at and the next 3 Downloaded by [Columbia University] at 10:47 03 February 2015 BIOLUMINESCENT ANALYSIS 2933 stages uf physical energy trda i n a BL rcacfion. A schcme given b&w p r m t s tht three sugp