A Fast, Low-Cost, and Environmental Friendly Micro-Flow-Batch Analyzer for Photometric Determination of Sulfites in Beverages

Tavares, Márcio R. S.; Andrade, Stéfani I. E.; Lima, Marcelo B.; Barreto, Inakã S.; Araújo, Mário C. U. de; Almeida, Luciano F.

doi:10.21577/0103-5053.20180243

Acessibilidade / Reportar erro

Brasil

Journal of the Brazilian Chemical Society

Español English

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

Short Report • J. Braz. Chem. Soc. 30 (5) • May 2019 • https://doi.org/10.21577/0103-5053.20180243 copy

A Fast, Low-Cost, and Environmental Friendly Micro-Flow-Batch Analyzer for Photometric Determination of Sulfites in Beverages

Authorship SCIMAGO INSTITUTIONS RANKINGS

An automated microsystem for sulfite determination in beverages was developed. It presents higher sampling throughput, lower chemical consumption and less waste generation than previous flow methods, while using the same p-rosaniline-formaldehyde-sulfite reaction. The sampling rate, limit of detection (LOD), and relative standard deviation (RSD) were estimated at 130 h^-1, 80.0 µg L^–1, and < 1.3% (n = 5), respectively. Recoveries ranged from 96.8 to 102.6%.

Keywords:
micro-flow-batch analyzer; sulfite; p-rosaniline-formaldehyde-sulfite reaction; beverage analysis

Step	Description	µP₁	µP₂	µP₃	µP₄	µP₅	Pulse	time / s	Volume / µL
1	addition of R₁, R₂ and sample	on	on	on	off	off	2	0.8	16^a a 16 µL of each R1, R2 and sample (total = 48 µL);
2	DM/NP activation for homogenization/reaction	off	off	off	off	off	-	2.0	-
3	absorbance measurement	off	off	off	off	off	-	1.0	-
4	emptying step of the µCH	off	off	off	off	on	5	2.0	-
5^b b steps 5 to 7 are carried out three times. µP1-µP5: solenoid metering micro-pumps; R1: formaldehyde solution; R2: p-rosaniline solution; DM: CD/DVD-ROM motor drive; NP: nylon paddle; µCH: micro-chamber.	addition of water	off	off	off	on	off	8	3.2	64
6^b b steps 5 to 7 are carried out three times. µP1-µP5: solenoid metering micro-pumps; R1: formaldehyde solution; R2: p-rosaniline solution; DM: CD/DVD-ROM motor drive; NP: nylon paddle; µCH: micro-chamber.	DM/NP activation for agitation	off	off	off	off	off	-	2.0	-
7^b b steps 5 to 7 are carried out three times. µP1-µP5: solenoid metering micro-pumps; R1: formaldehyde solution; R2: p-rosaniline solution; DM: CD/DVD-ROM motor drive; NP: nylon paddle; µCH: micro-chamber.	emptying step of the µCH	off	off	off	off	on	5	2.0	-

Sample	Initial concentration / (mg L^-1)	Recovery / %
Sample	Initial concentration / (mg L^-1)	0.50 mg L^-1	1.00 mg L^-1	2.00 mg L^-1
White wine	5.64	98.9 ± 2.3	99.3 ± 2.2	102.3 ± 2.5
White wine	4.45	99.5 ± 2.5	101.6 ± 2.4	97.8 ± 2.3
Red wine	7.55	97.5 ± 2.3	102.5 ± 1.9	101.6 ± 2.1
Red wine	4.80	99.8 ± 2.4	97.9 ± 2.2	102.4 ± 2.3
Whisky	2.56	97.6 ± 2.0	96.8 ± 2.1	102.6 ± 2.4
Whisky	2.03	101.8 ± 1.9	99.3 ± 2.3	101.5 ± 2.1
Beer	3.65	99.1 ± 2.2	98.5 ± 2.3	100.8 ± 2.5
Beer	1.69	102.2 ± 2.4	98.9 ± 2.4	102.4 ± 2.1

Sample	Reference		µFBA
Sample	Concentration ± SD / (mg L^-1)	RSD / %	Concentration ± SD / (mg L^-1)	RSD / %
White wine	5.23 ± 0.04	0.74	5.09 ± 0.03	0.60
	4.65 ± 0.05	1.07	4.72 ± 0.04	0.75
	4.89 ± 0.04	0.72	4.85 ± 0.03	0.52
	5.71 ± 0.05	0.80	5.64 ± 0.03	0.56
	4.38 ± 0.04	0.86	4.45 ± 0.04	0.92
Red wine	6.33 ± 0.04	0.65	6.39 ± 0.04	0.62
	7.69 ± 0.06	0.76	7.55 ± 0.06	0.77
	5.98 ± 0.06	1.02	6.05 ± 0.05	0.81
	5.24 ± 0.05	1.04	5.30 ± 0.04	0.66
	4.76 ± 0.04	0.84	4.80 ± 0.04	0.80
Whisky	2.63 ± 0.03	0.96	2.56 ± 0.02	0.82
	2.38 ± 0.03	1.24	2.34 ± 0.01	0.47
	1.96 ± 0.02	0.99	2.03 ± 0.01	0.59
Vodka	2.45 ± 0.02	0.87	2.51 ± 0.02	0.62
	3.88 ± 0.03	0.73	3.92 ± 0.02	0.56
	3.65 ± 0.03	0.81	3.72 ± 0.02	0.51
Beer	1.75 ± 0.02	1.17	1.69 ± 0.02	0.89
	3.67 ± 0.03	0.84	3.65 ± 0.02	0.68
	2.81 ± 0.02	0.78	2.87 ± 0.02	0.66

Parameter	µFBA (this work)	FBA¹¹11 Almeida Jr., P. L.; Bonfim, T. H. F.; Cunha, F. A. S.; Lima, K. M. G.; Aquino, J. S.; Almeida, L. F.; Anal. Methods 2018, 10, 448.	SIA¹²12 Segundo, M. A.; Rangel, A. O. S. S.; Anal. Chim. Acta 2001, 427, 279.	FIA¹³13 Mataix, E.; de Castro, M. D. L.; Analyst 1998, 123, 1547.	FIA¹⁴14 Lazaro, F.; de Castro, M. D. L.; Valcárcel, M.; Anal. Chem. 1987, 59, 950.
Limit of detection / (µg L^-1)	80.0	40.0	600	1.200	-
Working concentration range / (mg L^-1)	1.0-10.0	0.13-32.7	25-250	2.0-20	1.0-16.0
RSD / %	< 1.3 (n = 5)	< 3.1 (n = 5)	< 2.3 (n = 10)	< 3.0 (n = 3)	< 4.0
Sampling rate / h^-1	130	43	16	12	35
p-Rosaniline consumption per determination / µg	6	34	58	2500	267
Formaldehyde consumption per determination / µg	26	163	2339	8150	870
Sample consumption per determination / µL	16	1050	238	500	70
Waste generation perdetermination / mL	0.064	2.7	6.075	8.25	3.194
Detection strategy	photometer (integrated detection)	webcam (integrated detection)	spectrophotometer	spectrophotometer	spectrophotometer
Carrier fluid	absent	absent	hydrochloric acid (0.8 mol L^-1)	formaldehyde (1.0 g L^-1) / p-rosaniline (4.0 g L^-1)	formaldehyde (1.0 mg L^-1) / p-rosaniline (4.0 g L^-1)
Sample	beverages	vinegar	wines	wines	wines

Sociedade Brasileira de Química Instituto de Química - UNICAMP, Caixa Postal 6154, 13083-970 Campinas SP - Brazil, Tel./FAX.: +55 19 3521-3151 - São Paulo - SP - Brazil
E-mail: office@jbcs.sbq.org.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] *e-mail: laqa@quimica.ufpb.br