Protein and DNA Microarrays

A microarray (multiplex lab-on-a-chip) is a collection of microscopic protein or DNA spots (2D array) on a solid surface (a glass slide or silicon thin-film cell) that assays large amounts of biological material by high-throughput screening.

Our highly bright and photostable SeTau squaraine rotaxanes dyes exhibit high chemical stability in particular against oxidative reagents such as peroxides or ozone (see here) and therefore are excellent detection reagents for use in microarrays where the fluorescence signals of cyanine dyes such as Cy5 and  Alexa 647 are strongly dependent on the concentration of ozone during post-hybridization array washing. Controlled exposures of microarrays to ozone confirmed the susceptibility of cyanine dyes (Cy5 or Alexa 647) to ozone levels as low as 5-10 ppb for periods as short as 10-30 s.

Below is the confirming data by one of our Cancer Center customers:

Images courtesy of Kristin Lastwika, Postdoctoral Fellow.

The squaraine rotaxanes are available in reactive form with carboxy, NHS ester, DBCO and maleimide functionalities but also as hydrophobic probes for imaging.

			Excitation Light Sources												Characteristics
Product Number (Specs Sheet)	Product Name (Product Info)	Target Group	380	405	436	488	532	594	635	650	680	700	750	780	Medium	λ abs [nm]	ε [M –1 cm–1]	λ em [nm]	QY [%]	FLT [ns]	Buy
K8-3335 K8-3335	Seta-555-NHS Seta-555-NHS	NH2					•								PB 7.4	555	155000	570	7
K9-4119 K9-4119	SeTau-665-NHS SeTau-665-NHS	NH2								•	•	•			PB 7.4	664	160000	712	53	3.1
K9-4148 K9-4148	SeTau-647-Maleimide SeTau-647-Maleimide	SH							•	•					PB 7.4	648	200000	692	45	3.2
K9-4149 K9-4149	SeTau-647-NHS SeTau-647-NHS	NH2							•	•					PB 7.4	649	200000	695	61	3.2
K9-4169 K9-4169	SeTau-670-NHS SeTau-670-NHS	NH2							•	•	•				PB 7.4	673	275000	694	36	1.6
K8-3402 K8-3402	Zy3-NHS Zy3-NHS	NH2					•								PB 7.4	549	150000	564	4	0.3
K9-4179 K9-4179	SeTau-680-NHS SeTau-680-NHS	NH2							•	•	•				PB 7.4	683	295000	705	58	2.9

Seta-555-NHS (K8-3335) and SeTau-647-NHS (K9-4149) are amine-reactive dyes specifically developed for a wide range of DNA and protein microarray applications for the Cy3 and Cy5 channel. These reactive dyes are ideal for labeling of oligonucleotides, amino-modified cDNA, antibodies, peptides, and other types of biomolecules for microarray imaging applications.

 

 

Above is a comparison of our Seta-555 and SeTau-647 dyes with other dyes commonly used in these microarrays. The dyes were diluted 4x starting from 100ug/ml, 10 spots. The data shows much higher fluorescence signal coming from the Seta-555 and SeTau-647 dyes and there was also no detectable channel-to-channel crosstalk (data not shown).  These dyes are ideal for both, one- and two-color microarray measurements and have much higher ozone stability as compared to the dyes of our competitors. Try and experience the difference yourself!