Synthesis · Sub-Femtomolar, Label-Free Small-Molecule Sensing with Nanoarchitectonic Metal-Organic Frameworks

7 structured synthesis routes

Completeness describes how fully the route could be reconstructed from the main article and supporting information.

Complete recipeSource: Main

Route 1: Other

10 · 4. Experimental Section

Metal precursorsCuHITP/Cu(OH)2 extended-gate electrode

Linker precursorsMBS crosslinker and thiolated cortisol DNA aptamer

Solvents1:9 (v/v) DMSO/PBS for MBS; PBS for rinsing and blocking; Milli-Q water rinse

AdditivesMCH and BSA blocking reagents

Atmosphereroom temperature; humidified chamber for aptamer incubation

Temperatureroom temperature for surface steps; aptamer folded at 95 C then cooled

Time0.5 h MBS; >12 h aptamer; 0.5 h MCH; 0.5 h BSA

Substrate orientation50 uL droplets on CuHITP sensing electrode surface; 30 uL aptamer droplet in humidified chamber

Oxidant / reductantnone

Work-upRinsed with Milli-Q water after MBS, with PBS after aptamer incubation, with Milli-Q water after MCH, and with PBS before sensing.

ActivationCortisol aptamer solution heated to 95 C for 5 min and cooled to room temperature for 15 min to ensure folding before immobilisation.

Scalability contextDirect functionalisation uses intrinsic CuHITP -NH- groups, avoiding extra glutaraldehyde-style linkers.

Show 7 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	CuHITP/Cu(OH)2 electrode	one electrode	10 · 4. Experimental Section
Additive	m-maleimidobenzoyl-N-hydroxysuccinimide ester (MBS)	50 uL droplet · 1 mM in 1:9 DMSO/PBS	10 · 4. Experimental Section
Solvent	dimethyl sulfoxide (DMSO)	part of 1:9 DMSO/PBS	10 · 4. Experimental Section
Solvent	PBS	part of 1:9 DMSO/PBS; rinse/blocking medium · pH 7.2-7.6 stock; sensing uses 0.01X PBS	10 · 4. Experimental Section
Other	cortisol aptamer /5ThioMC6-D/ CGA CTG GTA GGC AGA TAG GGG AAG CTG ATT CGA TGC GTG GGT CG	30 uL droplet · 1 uM	10 · 4. Experimental Section
Additive	6-mercapto-1-hexanol (MCH)	50 uL droplet · 1 mM	10 · 4. Experimental Section
Additive	bovine serum albumin (BSA)	50 uL droplet · 0.5% w/v	10 · 4. Experimental Section

Partial recipeSource: SI

Route 2: Other

7 · Figure captions · Figure S8

Metal precursorsCu foil converted through a similar Cu(OH)2-templated CuHITP procedure

Linker precursorsnot separately reported; described as similar templated synthesis to the electrode route

Solventsnot separately reported for Cu foil fragment

Additivesnot separately reported for Cu foil fragment

Atmospherenot separately reported

Temperaturenot separately reported

Timenot separately reported

Substrate orientationCu foil, mechanically bent after conversion to delaminate a CuHITP film fragment

Oxidant / reductantnot separately reported

Work-upMechanical stress from extreme bending was applied after synthesis, causing film delamination for two-point probe measurement.

Activationnot separately reported

Scalability contextUsed only to obtain a free film fragment for two-point electrical characterisation.

Show 2 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Cu foil	not reported	7 · Figure captions · Figure S8
Linker	CuHITP linker precursor, not separately specified for the Cu foil fragment	not reported	7 · Figure captions · Figure S8

Complete recipeSource: Main

Route 3: Other

9 · 4. Experimental Section

Metal precursorspatterned 250 nm Cu layer on electrode

Linker precursorsnone

SolventsMilli-Q water, acetone, isopropanol, ethanol; AcOH cleaning bath

AdditivesNaOH and ammonium persulfate (APS)

Atmosphereroom temperature; N2 drying stream; ambient overnight drying

Temperatureroom temperature

Time0.05 h Cu(OH)2 growth; overnight ambient drying after N2 dry

Substrate orientationpatterned p-type Si(100) electrode with exposed Cu growth area

Oxidant / reductantAPS oxidant/etchant in concentrated NaOH solution converts Cu to Cu(OH)2 nanoarray

Work-upSequential sonication in Milli-Q water, acetone and isopropanol; AcOH immersion for 3 min to remove native copper oxide; rinse with Milli-Q water, acetone and isopropanol; after growth rinse with Milli-Q water and ethanol, dry under N2.

ActivationLeft overnight under ambient conditions to fully dry.

Scalability contextTemplate grows directly and selectively on patterned electrodes.

Show 8 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	patterned copper layer	250 nm Cu film	9 · 4. Experimental Section
Oxidant	ammonium persulfate (APS)	0.5 mL · 1 M	9 · 4. Experimental Section
Base	sodium hydroxide (NaOH)	1.5 mL · 10 M	9 · 4. Experimental Section
Solvent	Milli-Q water	5.5 mL in growth solution; also used for washing	9 · 4. Experimental Section
Acid	acetic acid (AcOH)	immersion for 3 min · not reported	9 · 4. Experimental Section
Solvent	acetone	sequential sonication/rinse	9 · 4. Experimental Section
Solvent	isopropanol	sequential sonication/rinse	9 · 4. Experimental Section
Solvent	ethanol	post-growth rinse	9 · 4. Experimental Section

Partial recipeSource: Main

Route 4: Other

9 · 4. Experimental Section

Metal precursorsAl, Ni, Ti and Cu metal deposition targets/sources; exact source purity not specified

Linker precursorsnone

Solventsphotolithography/lift-off solvents not specified

Additivesnone reported

Atmospheredeposition atmosphere not specified

Temperaturenot reported

Timenot reported

Substrate orientationp-type Si(100) wafer, single-side polished, resistivity 1-10 ohm cm

Oxidant / reductantnone for metal deposition

Work-upMetal layers patterned using a lift-off process to define selective Cu(OH)2/CuHITP growth area.

ActivationNo activation before metal patterning reported.

Scalability contextMicrofabrication-compatible patterned electrode stack.

Show 5 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	p-type Si(100) wafers	not reported · resistivity 1-10 ohm cm	9 · 4. Experimental Section
Metal Source	aluminum (Al)	10 nm layer	9 · 4. Experimental Section
Metal Source	nickel (Ni)	60 nm layer	9 · 4. Experimental Section
Metal Source	titanium (Ti)	10 nm layer	9 · 4. Experimental Section
Metal Source	copper (Cu)	250 nm layer	9 · 4. Experimental Section

Partial recipeSource: Main

Route 5: Other

9 · 4. Experimental Section

Metal precursorsCuHITP/Cu(OH)2 extended-gate electrode

Linker precursorsMBS crosslinker and thiolated scrambled DNA aptamer

Solventssame DMSO/PBS, PBS and water protocol as cortisol aptamer functionalisation

AdditivesMCH and BSA blocking reagents

Atmosphereroom temperature; humidified chamber for aptamer incubation

Temperatureroom temperature for surface steps; aptamer folding temperature not separately stated but inferred same protocol

Time0.5 h MBS; >12 h aptamer; 0.5 h MCH; 0.5 h BSA

Substrate orientationCuHITP sensing electrode surface under droplets

Oxidant / reductantnone

Work-upRinsed to remove non-covalently bound aptamers and blocking reagents, as for primary aptamer sample.

ActivationScrambled aptamer control has similar length and GC content; folding protocol not separately detailed beyond shared functionalisation workflow.

Scalability contextControl sample prepared to assess non-specific cortisol binding.

Show 5 structured reagent records

Role	Reagent	Amount / concentration	Source
Other	CuHITP/Cu(OH)2 electrode	one electrode	9 · 4. Experimental Section
Additive	MBS	50 uL droplet · 1 mM in 1:9 DMSO/PBS	9 · 4. Experimental Section
Other	scrambled aptamer /5ThioMC6-D/ CCA CCG CAG TCC GGT CGC TTG CTC GCT GTG TGG GTA GTA GGT CG	not separately reported · prepared as control with similar length and GC content	9 · 4. Experimental Section
Additive	MCH	50 uL droplet · 1 mM	9 · 4. Experimental Section
Additive	BSA	50 uL droplet · 0.5% w/v	9 · 4. Experimental Section

Complete recipeSource: Main

Route 6: Other

10 · 4. Experimental Section

Metal precursorsCu(OH)2 nanoarray on patterned electrode

Linker precursorsHATP.6HCl, the precursor to HITP

Solvents7 mL 1:1 (v/v) Milli-Q water/DMA mixture

AdditivesNaOAc for linker deprotonation

Atmosphereopen air

Temperature65

Time0.25

Substrate orientationpre-patterned Cu(OH)2 nanoarray on extended-gate electrode immersed in solution

Oxidant / reductantnone explicitly reported during conversion; NaOAc used for deprotonation

Work-upColour changed from bright blue to black; electrode rinsed thoroughly with a large amount of Milli-Q water and methanol.

ActivationDried under vacuum at 100 C for 3 h.

Scalability contextOn-chip solid-phase conversion avoids drop-casting and positions c-MOF directly on working electrodes.

Show 6 structured reagent records

Role	Reagent	Amount / concentration	Source
Metal Source	Cu(OH)2 nanoarray electrode	one patterned electrode	10 · 4. Experimental Section
Linker	HATP.6HCl	5 mg · in 7 mL total solution	10 · 4. Experimental Section
Base	sodium acetate (NaOAc)	4 mmol	10 · 4. Experimental Section
Solvent	Milli-Q water	part of 7 mL 1:1 v/v water/DMA	10 · 4. Experimental Section
Solvent	N,N-dimethylacetamide (DMA)	part of 7 mL 1:1 v/v water/DMA	10 · 4. Experimental Section
Solvent	methanol	post-reaction rinse	10 · 4. Experimental Section

Vague recipeSource: Main

Route 7: Solvothermal

4 · 2.1 Material Characterization · Figure 2c

Metal precursorsnot reported

Linker precursorsnot reported; likely HITP/HATP precursor but not specified in available text

Solventsnot reported

Additivesnot reported

Atmospherenot reported

Temperaturenot reported

Timenot reported

Substrate orientationnone; powder control

Oxidant / reductantnot reported

Work-upnot reported

Activationnot reported

Scalability contextConventional powder control only; no recipe details in available documents.