Large‐Scale Parallel Surface Functionalization of Goblet‐type Whispering Gallery Mode Microcavity Arrays for Biosensing Applications

Abstract

A novel surface functionalization technique is presented for large-scale selective molecule deposition onto whispering gallery mode microgoblet cavities. The parallel technique allows damage-free individual functionalization of the cavities, arranged on-chip in densely packaged arrays. As the stamp pad a glass slide is utilized, bearing phospholipids with different functional head groups. Coated microcavities are characterized and demonstrated as biosensors.

Densely Packed Microgoblet Laser Pairs for Cross‐Referenced Biomolecular Detection

“…Due to the sign of the drifts refractive index disturbances based on nonspecific his‐GFP adsorption can be excluded. This indicates the generally very good protein repulsion characteristics of the phospholipid inks already observed in previous publications 18, 22. As a result of all these disturbances, the sensing signal generated by the Ni‐chelated microlaser during the first and the second his‐GFP binding round shows significant differences.…”

Whispering gallery mode sensors

“…More recently, however, a modified process has been demonstrated allowing resonators of greater size, possessing larger wedge angles and exhibiting Q factors of 10 9 , to be made [46]. Goblet, or conical, polymer resonators are also emerging as a novel WGM resonator geometry, which lends itself to cheap and large-scale fabrication [47,48] and multiplexed functionalization [49]. Flexible coupling between goblet resonators has also been demonstrated [50] allowing potential utility in applications requiring mode tunability [51] (see also below).…”

“…This allows the functionalization procedure to be scaled up, so that many resonators can be modified in parallel. It was shown that different polymer (PMMA) microgoblet WGM laser biosensors can be modified with different chemicals using such a micro contact stamping technique [49]. The PDMS stamp was patterned with different chemicals (“inks”) by polymer pen lithography (see Fig.…”

“…(a) Large-scale uniform surface functionalization. (b) Multiplexed surface functionalization using an array of phospholipids with different functional head groups [49]. Copyright Wiley-VCH Verlag GmbH & Co. KGaA.…”

Taking detection to the limit with optical microcavities: Recent advances presented at the 560. WE Heraeus Seminar

“…These vast implementation opportunities raise many interesting questions related to the engineering aspects of practical sensor devices. Many different cavity geometries have been explored in this vein, microspheres [68], toroidal shaped cavities [25,69], goblets [70][71][72], hollow core resonators [47], microbubbles [73,74], bottle resonators [75][76][77][78][79][80], polymer ring resonators [81][82][83], silicon ring resonators [5,84,85], silicon ring resonators in reaction tubes and on fiber ends [86,87], as well as other ones.…”