Despite the continuous advancements in bio-molecular detection and fluidic systems integration, the realization of portable and high performance devices for diagnostic applications still presents major difficulties, mostly because of the need to combine adequate sensitivity with low cost of production and operational simplicity and speed. In this context, we propose a compact device composed of a smartphone and a custom-designed cradle, containing only a disposable sensing cartridge, a tiny magnetic stirrer and a few passive optical components. The detection principle is the previously proposed Reflective Phantom Interface that is based on measuring the intensity of light reflected by the surface of an amorphous fluoropolymer substrate, which has a refractive index very close to that of the aqueous sample solution and hosts various antibodies immobilized within spots. The reflectivity of dozens of spots is monitored in real time by the phone׳s camera using the embedded flash LED as the illumination source. We test the performance of the combined device targeting heterologous immunoglobulins and antigens commonly used as markers for diagnoses of hepatitis B and HIV. Target concentrations as low as a few ng/ml can be rapidly and robustly determined by comparing the rate of increase of the signal after the addition of the sample with that measured after the subsequent addition of a standard solution with known concentration. The features of the proposed system enable the realization of novel handheld biosensing devices suitable for those applications where multiple targets have to be rapidly detected even without the presence of trained personnel.

A fast and simple label-free immunoassay based on a smartphone / F. Giavazzi, M. Salina, E. Ceccarello, A. Ilacqua, F. Damin, L. Sola, M. Chiari, B. Chini, R. Cerbino, T. Bellini, M. Buscaglia. - In: BIOSENSORS & BIOELECTRONICS. - ISSN 0956-5663. - 58:(2014 Aug 15), pp. 395-402. [10.1016/j.bios.2014.02.077]

A fast and simple label-free immunoassay based on a smartphone

F. Giavazzi
Primo
;
M. Salina
Secondo
;
E. Ceccarello;R. Cerbino;T. Bellini
;
M. Buscaglia
Ultimo
2014

Abstract

Despite the continuous advancements in bio-molecular detection and fluidic systems integration, the realization of portable and high performance devices for diagnostic applications still presents major difficulties, mostly because of the need to combine adequate sensitivity with low cost of production and operational simplicity and speed. In this context, we propose a compact device composed of a smartphone and a custom-designed cradle, containing only a disposable sensing cartridge, a tiny magnetic stirrer and a few passive optical components. The detection principle is the previously proposed Reflective Phantom Interface that is based on measuring the intensity of light reflected by the surface of an amorphous fluoropolymer substrate, which has a refractive index very close to that of the aqueous sample solution and hosts various antibodies immobilized within spots. The reflectivity of dozens of spots is monitored in real time by the phone׳s camera using the embedded flash LED as the illumination source. We test the performance of the combined device targeting heterologous immunoglobulins and antigens commonly used as markers for diagnoses of hepatitis B and HIV. Target concentrations as low as a few ng/ml can be rapidly and robustly determined by comparing the rate of increase of the signal after the addition of the sample with that measured after the subsequent addition of a standard solution with known concentration. The features of the proposed system enable the realization of novel handheld biosensing devices suitable for those applications where multiple targets have to be rapidly detected even without the presence of trained personnel.
Biomolecular detection; Immunoassay; Optical biosensor; Point-of-care; Protein microarray; Reflective phantom interface
Settore FIS/07 - Fisica Applicata(Beni Culturali, Ambientali, Biol.e Medicin)
   Next Generation Biomimetic Analytical Platforms. Building Blocks for Ubiquitous Environmental Sensor Networks
   NAPES
   EUROPEAN COMMISSION
   FP7
   604241
15-ago-2014
Article (author)
File in questo prodotto:
File Dimensione Formato  
2014 B&B.pdf

accesso solo dalla rete interna

Tipologia: Publisher's version/PDF
Dimensione 3.21 MB
Formato Adobe PDF
3.21 MB Adobe PDF   Visualizza/Apri   Richiedi una copia
Pubblicazioni consigliate

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2434/234967
Citazioni
  • ???jsp.display-item.citation.pmc??? 11
  • Scopus 81
  • ???jsp.display-item.citation.isi??? 72
social impact