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XanTec 3D surface

XanTec 3D hydrogel sensor chips

In the table below the 3D hydrogel sensor chips available at XanTec (1) are shown. Several surface thicknesses are offered and in addition three surface densities are available: Low, Medium and Dense. 3D immobilization matrices allow multilayer ligand immobilization which leads to significant signal amplification. They are employed for qualitative screening, concentration determinations and detection and kinetic analysis of low molecular weight compounds. As a rule of thumb, the smaller the analyte is, the thicker and denser the hydrogel structure should be.

Two new surfaces for click chemistry (azide (AZD) and DBCO (DCD)) are available which have advantages over e.g. streptavidin or Ni-NTA surfaces. Further information can be found at (Xantec).

The new zwitterionic surface (ZC and ZCC) has been developed for particularly acidic or sensitive proteins that need to be covalently immobilized. In order to achieve a pre-concentration of strongly acidic, negatively charged ligands in the hydrogel, the charges were simply reversed during immobilization. Here the actually neutral, zwitterionic surface is temporarily positively charged during the activation of the carboxyl groups with NHS/EDC, so that negatively charged ligands can enter into electrostatic interaction with the surface.

XanTec flat surface

Table: 3D hydrogel surfaces
Name	Surface coating	Functionalities	Thickness (nm)	Densities ^*
AG	Agarose hydrogel	hydroxy	approx. 200	-
AL	Alginate hydrogel	carboxyl	approx. 100
AZD	CM dextraan	azide	50, 200	L, M
AZHC	Polycarboxylate	azide	30, 1500	M
BHC	Polycarboxylate	biotin	30, 200, 1000, 1500	M
C	Polycarboxylate, high charge density	carboxyl	30, 80, 200	M, D
CMC	Cellulose	carboxymethyl	approx. 200	-
CMD	CM dextran	carboxymethyl	50, 200, 500, 700	L, M, D
CMPEG	Polyethyleneglycol, 6kDa	carboxymethyl	approx. 100	-
CS	Polycarboxylate, partially sulfonated	carboxyl	30, 80, 150	M, D
D	Dextran	hydroxyl	50, 200, 500	L, M, D
DCD	CM dextraan	DBCO	50, 200	L, M
GEL	Gelatine	-	approx 200.	-
HC	Polycarboxylate, medium charge density	carboxyl	30, 200, 1000, 1500	M
HLC	Polycarboxylate, low charge density	carboxyl	30, 200, 1000, 1500	M
HY	Hyaluronic acid	carboxyl	approx. 100	-
HZHC	Polycarboxylate	hydrazide modified	30, 200, 1000	M
HEP	Heparin	carboxyl	approx. 50	-
LD	CM dextraan	partially alkyl derivatised	approx. 200	-
NIHC	Polycarboxylate	NTA polyvalent	30, 200, 1000	M
NID	CM dextran	NTA	50, 200, 500, 700	L, M, D
PAGHC	Polycarboxylate	protein A/G	30, 200,1000, 1500	M
PAGD	CM dextran brush conformation	protein A/G	50, 200, 500, 700	L, M
PC	Pectin hydrogel	carboxyl	approx 200	-
PEG	Polyethyleneglycol, 6 kDa	hydroxyl	approx 100	-
PLY	Poly-L-lysine	primary amine	approx. 300	-
SAHC	Polycarboxylate	streptavidn	30, 200, 1000, 1500	M
SAD	CM dextran	streptavidin	50, 200, 500, 700	L, M, D
THC	Polycarboxylate	disulfide modified	30, 200, 1000, 1500	M
TD	CM dextran	disulfide modified	50, 200, 500, 700	L, M, D
UVD	CM Dextran	UV crosslinker	50, 200, 500, 700	-
ZC	Polycarboxylate	Zwitterionic, neutral. cationic after NHS activation	30, 80	M
ZCC	Polycarboxylate	Cationic, zwitterionic for preconcentration scouting	30, 80	M

^*Densities L: low; M: medium; D: dense / Not all combinations are available.

References

(1)	XanTec- XanTec website. (2019). Goto reference