Green Synthesis, Wastewater Cleanup and Precision Detection: The Rise of Periodate Chemistry

and Chemical Sensing

A new review explores how an iodine-based oxidant called periodate could become increasingly useful in cleaner chemical manufacturing, wastewater treatment, pharmaceutical production and highly sensitive chemical sensing. The study, 'Redox chemistry, catalysis, and electrochemical detection of periodate species: sensors, mechanisms, and applications in green chemistry,' by Ruba Alrajhi, Fatehy M. Abdel-Haleem, Mikhael Bechelany and Ahmed Barhoum, was published in Frontiers in Chemistry in August 2026. The researchers bring together recent knowledge on periodate chemistry, catalytic reactions, electrochemical production and sensing technologies, with particular attention to environmental and green-chemistry applications.

The researchers describe periodate species as strong oxidizing agents with applications ranging from environmental remediation and active pharmaceutical ingredient production to advanced oxidation processes and analytical chemistry. The growing interest is tied to a useful combination of strong redox activity, selective reactions and the possibility of detecting or regenerating periodate electrochemically.

Why Periodate Has Become an Important Green Oxidant

Periodate contains iodine in its highest oxidation state of +7, giving it strong electron-accepting properties and making it capable of oxidizing many organic and inorganic compounds. Its chemistry is particularly useful for breaking carbon- carbon bonds between neighbouring hydroxyl groups, a process known as the Malaprade reaction, which can transform vicinal diols and related compounds into aldehydes, ketones or other carbonyl products.

This selective chemistry explains why periodate has found uses in carbohydrate analysis, pharmaceutical synthesis, biochemical research and fine-chemical manufacturing. It can react with alcohols, sugars, amino alcohols, amino acids and many other compounds, creating opportunities not only for synthesis but also for indirect chemical measurement, where researchers determine an analyte by measuring how much periodate it consumes.

Periodate exists in several protonated, hydrated and dimerized forms in water, with the balance among these species influencing oxidation strength, reaction speed and electrochemical response. Under strongly acidic conditions, its standard oxidation potential can approach +1.6 V, while under highly alkaline conditions it falls to roughly +0.7 V, making acidic or near-acidic environments particularly favourable for many oxidation reactions. Controlling pH is therefore central to designing periodate reactions and reliable sensors.

Traditional periodate production can involve chlorine gas and other chemical oxidants, bringing toxicity, unwanted by-products and separation problems. Electrochemical synthesis provides a cleaner route because current density, electrode potential, temperature, electrolyte and pH can be controlled precisely. Boron-doped diamond electrodes are especially promising because they are chemically resistant, non-toxic, difficult to foul and capable of operating in harsh acidic or alkaline environments.

Researchers have even demonstrated self-cleaning electrochemical systems in which organic contaminants are mineralized while iodate is converted back into periodate, opening the possibility of recycling the oxidant instead of treating it as a single-use chemical.

From Pharmaceutical Production to Polluted Water

Periodate-based advanced oxidation processes can attack difficult organic pollutants through radical formation, electron transfer, oxygen transfer and metal-assisted reaction pathways. Reported targets include dyes, pesticides, pharmaceuticals, phenols, endocrine-disrupting chemicals and other persistent industrial contaminants.

Periodate can be activated electrochemically, photochemically, biologically or through metal and nanomaterial catalysts, generating highly reactive species capable of breaking down contaminants that resist conventional treatment. These systems can sometimes combine pollutant oxidation with disinfection while reducing chemical and energy requirements.

A recent electrochemical–catalytic approach using a FeMo@C-coated graphite felt cathode illustrates how much performance can improve when electrochemistry and catalysis are combined. The system achieved an apparent degradation rate of 0.35 min⁻¹ and a synergy index of 9.3, while remaining effective in real water matrices. Mechanistic testing indicated that iodate radicals were the dominant reactive species.

Periodate has been used to prepare pharmaceutical ingredients including bosentan, flustramine B, physostigmine and phenserine. The review notes that periodate-assisted pharmaceutical synthesis can reduce reaction time, waste, impurities and production costs, showing that the environmental value of this chemistry extends beyond wastewater treatment.

Electrochemical Sensors Push Detection to Tiny Concentrations

Knowing how much periodate is present becomes essential when it is used in manufacturing, water treatment or analytical reactions. Electrochemical detection is attractive because instruments can be relatively inexpensive, compact and fast while requiring small quantities of reagents. Researchers have mainly explored three approaches: potentiometry, amperometry and voltammetry.

Potentiometric sensors are among the simplest and most portable, often using ion-selective membranes that translate periodate concentration into a measurable electrical potential. They can support continuous monitoring and flow-injection analysis, yet many existing designs rely on ion-exchange mechanisms that can struggle with selectivity and interference in complex samples. Ionophore-based membranes offer a promising alternative because molecular recognition could improve selectivity and stability.

Amperometry measures current produced during periodate oxidation or reduction and provides the highest sensitivity of the three main approaches reviewed, with some nanostructured systems reaching nanomolar detection levels. Voltammetry also provides strong selectivity, rapid measurements and opportunities for miniaturization, making it attractive for environmental, pharmaceutical and industrial monitoring.

Nanotechnology has changed what these sensors can achieve. Carbon nanotubes, metal oxides, nanoparticles, conducting polymers and metal-complex catalysts can accelerate electron transfer, lower the required operating potential and strengthen the analytical signal. Modified electrodes have pushed periodate measurements from micromolar toward nanomolar concentrations, although complicated electrode fabrication, fouling, reproducibility and long-term stability remain practical barriers. Voltammetric platforms in particular could eventually be combined with microelectronics for portable, real-time measurements outside conventional laboratories.

Periodate sensing is useful for more than measuring periodate itself because the oxidant reacts predictably with carbohydrates, glycerol, ascorbic acid, amino acids and other compounds. Researchers can measure the remaining periodate or resulting products to indirectly determine these substances in beverages, pharmaceuticals, food, industrial materials and biological samples.

Portable Sensors and Recyclable Chemistry Shape the Next Step

Periodate chemistry also offers an unusual route to detecting tiny quantities of metals. Trace amounts of manganese, chromium, iron, rhodium, iridium and vanadium can accelerate periodate oxidation, allowing the change in reaction rate to reveal how much metal is present. Some approaches can reach micro-, nano- and even sub-nanogram levels.

This principle has already moved toward portable analysis; for example, Manganese has been measured through periodate-driven colour reactions captured by a smartphone camera and analysed digitally, showing how classical oxidation chemistry could be paired with everyday electronics for field testing.

Several problems still stand between laboratory performance and widespread practical use. Real samples contain substances that can interfere with periodate reactions, electrodes may become fouled or lose activity, catalytic behaviour can depend strongly on pH and ionic strength, and researchers still lack a complete mechanistic picture of the reactive intermediates involved.

The authors identify greener large-scale periodate production, reusable and stable electrodes, improved understanding of reactive species and better optimization of operating conditions as major research priorities. New ionophores could make simple potentiometric sensors more selective and reversible in complex samples, while systematic research connecting periodate speciation with catalytic activity, electrochemical performance and analytical sensitivity is still needed.

Periodate's ability to connect selective chemical transformations, pollutant destruction, pharmaceutical synthesis, trace analysis, electrochemical regeneration and portable sensing gives it a particularly broad place in emerging green chemistry. The next challenge is turning highly sensitive laboratory systems into durable, affordable technologies that can recycle their chemistry, withstand real-world samples and deliver reliable measurements wherever they are needed.