Chemiluminescence microfluidic system of gold nanoparticles enhanced luminol-silver nitrate for the determination of vitamin B12.
A rapid and sensitive chemiluminescence (CL) system coupled with a microfluidic chip has been presented to determine vitamin B12 (VB12) based on the reaction of luminol and silver nitrate (AgNO(3)) in the presence of gold nanoparticles (AuNPs). A microfluidic chip was fabricated by a soft-lithographic procedure using polydimethyl siloxane (PDMS) having four inlets and one outlet with a 200 μm wide, 250 μm deep, and 100 mm long microchannel. Ag(+) was used as a chemiluminogenic oxidant in this CL reaction which oxidized luminol to produce strong CL signal in the presence of AuNPs. Luminol reacted with AgNO(3) under the catalysis of AuNPs to produce luminol radicals which reacted with dissolved oxygen and emitted CL light. The proposed CL system was applied to determine the amount of VB12 in VB12 tablets and multivitamin. Under the optimum conditions, the CL intensity of the system was increased with the concentration of VB12 in the range of 0.25-100 ng mL(-1) with the correlation coefficient of 0.9982. The limit of detection was found to be 0.04 ng mL(-1) with the relative standard deviation of 1.56 % for five replicate determinations of 25 ng mL(-1) of VB12. The CL reaction mechanism was demonstrated by UV-visible spectra and CL emission spectra.
Department of Chemistry, Kyungpook National University, Daegu, 702-701, South Korea.
Mohammad
M
Kamruzzaman
Al-Mahmnur
AM
Alam
Kyung Min
KM
Kim
Sang Hak
SH
Lee
Young Ho
YH
Kim
A N M Hamidul
AN
Kabir
Gyu-Man
GM
Kim
Trung Dung
TD
Dang
D004339:Drug Compounding; D006046:Gold / Q000737:chemistry*; D008163:Luminescent Measurements / Q000295:instrumentation*; D008165:Luminol / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D012835:Silver Nitrate / Q000737:chemistry*; D014805:Vitamin B 12 / Q000032:analysis* / Q000737:chemistry
D008165:Luminol; D006046:Gold; D012835:Silver Nitrate; D014805:Vitamin B 12