Microfluidic flow injection thermal lens microscopy for high throughput and sensitive analysis of sub-[mu]L samples

Mingqiang Liu (Avtor), Sara Malovrh (Avtor), Mladen Franko (Avtor)

Povzetek

An analytical method combining microfluidic flow injection analysis (μFIA) with thermal lens microscopy (TLM) was developed for high throughput and sensitive analysis of sub-μL samples. Performance of the μFIA-TLM was validated for detection of hexavalent chromium [Cr(VI)] in water samples. At different sample injection volumes, detection positions and flow rates, influences of the reaction time and the diffusion of Cr-diphenylcarbazone (DPCO) complexes on the μFIA-TLM signal were investigated. Photodegradation of the Cr-DPCO complex was clearly observed when the absorbed photons per Cr-DPCO is above 1600. After optimization of the TLM with respect to rapid flows (up to 10 cm/s), we achieved a limit of detection of 0.6 ng/mL for Cr(VI) in a 50-μm deep channel. Impacts of interfering ions [V(V), Mo(VI), Fe(III)] on the Cr(VI) determination were found to be small. Cr(VI) in real samples from a cement factory were determined and found in good agreement with results of spectrophotometry. This μFIA-TLM shows advantages over its conventional counterpart, such as eliminating additional sample conditioning, reducing over 100 times the sample consumption to sub-μL and over 10 times the time required for one sample injection to a few seconds (up to 20 samples/min). The optimized μFIA-TLM setup can be applied for fast and sensitive analysis of nonfluoresent sub-μL samples in rapidly flowing mediums.

Ključne besede

spektrometrija TLS;mikroskopija TLM;mikrofluidika;krom (VI);

Podatki

Jezik:	Angleški jezik
Leto izida:	2016
Tipologija:	1.01 - Izvirni znanstveni članek
Organizacija:	UNG - Univerza v Novi Gorici
UDK:	543.2/.9
COBISS:	4365051
ISSN:	1759-9660
Št. ogledov:	4417
Št. prenosov:	261
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

URN:	URN:SI:UNG
Vrsta dela (COBISS):	Delo ni kategorizirano
Strani:	str. 5053-5060
Letnik:	ǂVol. ǂ8
Zvezek:	ǂiss. ǂ25
Čas izdaje:	2016
DOI:	10.1039/C6AY00932H
ID:	9148264