MACS Matchmaker

Fc-receptor capture — protocol

For Fc-effector profiling and antibody PK / half-life screening, lino Biotech supplies pre-conjugated Fc-receptor–oligo adapters that hybridize directly to any Oligo|PEG chip. No off-chip conjugation, no IMAC step — flow the adapter, then flow the antibody analyte. Two ready-to-use adapters cover the common questions: a multiplexable FcγR adapter (FcγRI, FcγRIIa, FcγRIIb, FcγRIIIa, FcγRIIIb) and a dedicated FcRn adapter for pH-dependent IgG recycling kinetics.

Before you start

Read Safety & Compliance and the safety data sheet for every reagent below. The SDS, not this page, governs how a reagent is handled, stored and disposed of.
Use the personal protective equipment and the waste route your laboratory prescribes for these reagent classes.
Check this protocol against the materials actually in hand: confirm the intended Seq ID, the product revision, the lot-specific certificate and the instructions supplied with it. Where those differ from this page, the documentation supplied with the material governs.

Strategy: pre-conjugated adapter, then antibody analyte

Each adapter ships as a 110 µL stock at 2.6 µM in PBST — enough for 10 immobilizations at the recommended 200 nM working concentration (130 µL injection volume). The Fc receptor is supplied already-conjugated to a chosen oligonucleotide sequence (Seq ID 01–64), so multiple receptors with distinct Seq IDs can be loaded onto separate ridge positions in a single hybridization step.

The Fc receptor holds the IgG by its constant region, leaving both antigen-binding sites free. Orientation comes from the architecture rather than from the coupling chemistry.

FcγR / FcRn–oligo hybridization. Flow the adapter (or a multiplex mix) at 200 nM in PBST over the Oligo|PEG chip for 5 min. The oligo hybridizes to the matching ridge sequence, loading the Fc receptor on the surface.
Antibody analyte injection. Run the antibody concentration series. Each receptor spot returns a separate sensorgram; for FcRn, run the binding phase at pH 6.0 and dissociate with pH 7.4 buffer.
Regeneration. Strip the DNA duplex with 3 M GuHCl + 125 mM NaOH (400 µL/min, 0.5 min) to reload fresh receptor for the next antibody.

For non-standard or engineered Fc constructs not in the catalogue, conjugate the receptor off-chip with the AminoLink kit and load it the same way.

Adapter selection

Adapter	Receptors covered	Best for	Webshop
Oligo Adapter Fc gamma receptors (FcγRs)	FcγRI (CD64), FcγRIIa (CD32a), FcγRIIb (CD32b), FcγRIIIa (CD16a), FcγRIIIb (CD16b) — all human; one Seq ID per receptor ordered	Fc-effector profiling across IgG subclasses; multiplex panels for engineered Fc variants	110 µL stock — view in shop
Oligo Adapter FcRn	Human FcRn (Neonatal Fc Receptor)	Antibody PK / half-life prediction; pH-dependent IgG recycling kinetics (binding pH 6.0, release pH 7.4)	110 µL stock — view in shop

Both adapters share the chip format and can be combined in a single multiplex hybridization when their Seq IDs differ — profile FcγR binding and FcRn recycling for the same antibody in one experiment.

Protocol

Step 1 — Adapter hybridization

Parameter	Value
Adapter stock	110 µL at 2.6 µM in PBST (10 immobilizations per vial)
Working dilution	200 nM in PBST, 130 µL per injection
Flow rate / contact time	10 µL/min, 5 min
Chip type	Oligo\|PEG (8×8 default; 6×9 on request)
Multiplex	Mix multiple adapters (different Seq IDs) at 200 nM each to load several receptors in one injection

Step 2a — Antibody analyte (FcγR adapter, pH 7.4)

Parameter	Value
Buffer	PBST, pH 7.4
SCK association concentration range	0.1–100 nM (high-affinity FcγRI), 1–1000 nM (low-affinity FcγRII / III)
SCK association flow rate / contact time	30 µL/min (6-ch) / 60 µL/min (3–4-ch) / 100 µL/min (1-ch), 2 min
SCK dissociation	PBST, 200 µL/min, 2 min (extend for slow off-rates)

Step 2b — Antibody analyte (FcRn adapter, pH 6.0)

Parameter	Value
Binding buffer	50 mM phosphate / 150 mM NaCl / 0.05 % Tween-20, adjusted to pH 6.0
SCK association concentration range	10–1000 nM (FcRn affinity is moderate even at pH 6.0)
SCK association flow rate / contact time	30 µL/min (6-ch) / 60 µL/min (3–4-ch) / 100 µL/min (1-ch), 2 min
SCK dissociation	PBST pH 7.4, 200 µL/min, 2 min — IgG releases rapidly at neutral pH

Step 3 — Regeneration

Parameter	Value
Regeneration solution	3 M GuHCl + 125 mM NaOH
Flow rate / contact time	400 µL/min, 0.5 min
After strip	Re-hybridize the FcγR / FcRn adapter for the next antibody

Reference protocol parameters

Parameter	FcγR adapter	FcRn adapter
Stock	110 µL at 2.6 µM in PBST (10 immobilizations per vial)
Working concentration	200 nM, 130 µL injection
Hybridisation	10 µL/min, 5 min, Oligo\|PEG chip
Antibody analyte concentration	0.1–100 nM (FcγRI) / 1–1000 nM (FcγRII–III)	10–1000 nM
Binding buffer pH	7.4	6.0 (binding) / 7.4 (release)
SCK association	30 µL/min (6-ch) / 60 µL/min (3–4-ch) / 100 µL/min (1-ch), 2 min
SCK dissociation	200 µL/min, 2 min (PBST or pH 7.4 release)
Regeneration	3 M GuHCl + 125 mM NaOH, 400 µL/min, 0.5 min

QC and acceptance

Confirm the pH before interpreting anything. These receptors are pH-dependent by design, and buffer pH decides whether binding is observable at all rather than merely how strong it looks. FcRn is the extreme case: it binds IgG at pH 6.0 and releases at pH 7.4, so running an FcRn experiment at neutral pH produces a correct-looking measurement of nothing. Verify the pH of the buffer actually on the instrument, not the label on the bottle.
Run a known antibody. Include an IgG whose behavior against the adapter you are using is already established, on the same chip and in the same run. Without it, an inactive receptor preparation, a mis-set pH and a genuine non-binder are indistinguishable — all three give a flat sensorgram.
Adapter loaded. The receptor–oligo adapter injection gives a response that persists through the wash, before any antibody is injected.