The nanotech solution for long acting drug delivery

DelSiTechTMSilica is an advanced delivery technology for parenteral and local administration of injectable depot,implant and eye drop dosage forms.  The proprietary technology is based on Silica (silicon dioxide, SiO2 ) Matrix into which the active ingredient is embedded. The matrix can be designed to biodegrade at the required rate to assure a tightly controlled release of the active substance over extended periods of time, providing a better therapeutic effect in situ and causing lower systemic and local adverse events than alternative delivery systems.

The technology was developed at the University of Turku and Åbo Akademi University by the Biomaterial Research Group in Turku, Finland and is fully owned and patented by DelSiTech.

Silica Drug Delivery Matrix

Silica – The natural solution for drug delivery

DelSiTech has developed a unique proprietary drug delivery technology based on biodegradable Silica (SiO2 ) Matrix into which an active substance is embedded.

DelSiTechTMSilica Matrix is formed in an aqueous solution by the polymerization of alkoxysilanes, Si(OR)4, using a technique known as the sol-gel process. The resulting silica matrix is porous at the nanoscale and contains a varying number of OH groups and water. By changing the manufacturing process parameters, it is possible to vary the number of the OH groups and specific surface area (from a dense gel to highly porous), both having an influence on the biodegradation rate of silica. When silica gel comes into contact with body fluids, the matrix is slowly dissolved. The dissolution of the matrix takes place mainly through an erosion mechanism.The biodegradation process does not change the pH within silica gel nor in the surrounding tissue in contrast to most commonly used alternative drug delivery matrices.

Technology with multiple applications

With DelSiTech™Silica, it is possible to administer parenteral controlled release drugs more precisely, safely and cost-effectively than with other alternative drug delivery technologies.

DelSiTech’s drug delivery technology can be applied to an unlimited number of therapeutic indications.The Silica Matrix is suitable for the delivery of all types of molecules; small molecule compounds, peptides, RNA, proteins, antibodies, complex carbohydrates and even viruses have been encapsulated and delivered successfully. Multiple administration routes (subcutaneous, intramuscular, intraocular, intratumoural) can be used and various periods of release (1 day to 12 months) can be achieved.

Although mainly focused on delivery of therapeutic substances, the silica-based technology can be also used in other industry areas such as in diagnostics, agrochemistry and chemical environmental control.

Please contact us for a confidential discussion on the suitability of our technology to your specific application.


The silica-based drug delivery technology has multiple competitive advantages over other alternative delivery technologies


Silica is a natural, endogenous component of the body

  • Fully biocompatible and non-toxic in living tissue
  • Silica has no metabolism – dissolved silica is freely carried away in tissue fluids and excreted unchanged via urine in the form of silicic acid
  • Silica gel has been recognized by FDA as a GRAS material (Generally Regarded As Safe)


  • Suitable for small molecules, biomolecules, viruses and even cells
  • Suitable for highly water soluble and poorly water soluble compounds
  • Administration in various dosage forms: microparticles, solid implants, gels, and depot injections


  • Silica is fully biodegradable by dissolution in body fluids
  • Drug release strictly controlled by silica surface erosion
  • Silica dissolution can be adjusted from days to many months
  • Initial burst well controlled

Selected publications

The silica-based drug delivery technology and its scientific basis has been validated in numerous scientific studies

A selection of publications related to DelSiTechTMSilica Matrix.

Tyagi P, Koskinen M, Mikkola J, Sarkhel S, Leino L, Seth A, Madalli S, Will S, Howard VG, Brant H, Corkill D. Injectable Biodegradable Silica Depot: Two Months of Sustained Release of the Blood Glucose Lowering Peptide, Pramlintide. Pharmaceutics. 2022; 14(3):553.

Noppari P, Jokinen M, Dargelas F, Mikkola J, Leino L. (2021). CHAPTER 9. Parenteral Delivery of Therapeutic Proteins, Peptides and Small Molecules Using Biodegradable Silica. 10.1039/9781839164958-00188

Forsback AP, Noppari P, Viljanen J, Mikkola J, Jokinen M, Leino L, Bjerregaard S, Borglin C, Halliday J. Sustained in-vivo release of triptorelin acetate from a biodegradable silica depot: Comparison to Pamorelin® LA. Nanomaterials 2021, 11, 1578.

Noppari P, Forsback AP, Terjung C, MarttilaA, Leino L, Unger F, Baerfacker L, Dargelas F, & Reay M. Development of injectable long-acting controlled release intravitreal depot of BAY224 using biodegradable silica microparticle-silica hydrogel composite. Investigative Ophthalmology & Visual Science. 2020, 61(7), [1357].

Tyagi P, Koskinen M, Mikkola J, Leino L, Schwarz A.. Silica microparticles for sustained zero-order release of an anti-CD40L antibody. Drug Del & Trans Res (2017)

Mika Jokinen, Cora Griffin, Lasse Leino. New Solutions for Ophthalmic Drug Delivery Using Biodegradable Silica Matrix. ONdrugDelivery (2016)

Koskimäki J, Tarkia M, Ahtola-Sätilä T, Saloranta L, Simola O, Forsback AP, Frantzen J. Intracranial biodegradable silica-based nimodipine drug release implant for treating vasospasm in subarachnoid hemorrhage in an experimental healthy pig and dog model. BioMed Research International, 2015, Article ID 715752

Kangasniemi L, ParviainenS, Pisto T, Koskinen M, Jokinen M, Kiviluoto T, Cerullo V, Jalonen H, Koski A, Kangasniemi A, Kanerva A, Pesonen S, Hemmink A, Effects of capsid-modified oncolytic adenoviruses and their combinations with gemcitabine or silica gel on pancreatic cancer, International Journal of Cancer, Volume 131 (1), 2012, pp.253–263.

Kangasniemi L, Koskinen M, Jokinen M, Ala-Aho R, Kähäri V-M, Toriseva M, Jalonen H, Ylä-Herttuala S, Moilanen H, Stenman U-H, Kanerva A, Pesonen S, Hakkarainen T, and Hemminki A, Extended release of adenovirus from silica implants in vitro and in vivo, Gene Therapy 16(1).(2009), pp. 103 – 110.

Jokinen M, Koskinen M, Areva S, Rationale of using conventional sol-gel derived SiO2 for delivery of biologically active agents. Progress in Bioceramics: Key Engineering Materials 377, (2008),195-210.

Viitala R, Jokinen M, Rosenholm JB. Mechanistic studies on release of large and small molecules from biodegradable SiO2 .Int. J. Pharm. 336 (2007) p. 382-390.

Viitala R, Jokinen M, Maunu S-L, Jalonen H,Rosenholm JB, Chemical characterisation of bioresorbable sol-gel derived SiO2 matrices prepared at protein-compatible pH. J. Non- Crystalline Sol. 351 (2005) p.3225-3234.

Viitala R, Jokinen M, Tuusa S, Rosenholm JB andJalonen H, Adjustably biodegradable sol-gel derived SiO2 matrices for protein release. J. Sol-Gel Sci. Tech. 36 (2005) p. 147-156.

Kortesuo P, Ahola M, Kangas M, Jokinen M, LeinoT, Vuorilehto L, Laakso S, Kiesvaara J, Yli-Urpo A, Marvola M. Effect of synthesis parameters of the sol-gel- processed spray dried silica gel microparticles on the release rate of dexmedetomidine hydrochloride. Biomaterials23(2002) 2795-2801.

Kortesuo P, Ahola M, Kangas M, Yli-Urpo A,Kiesvaara J, Marvola M. In vitro release of dexmedetomidine from silica xerogel monoliths: effect of sol-gel formulation parameters. Int. J. Pharm. 212 (2001)121-130.

Kortesuo P, Ahola M, Kangas M, Karlsson S,Kangasniemi I, Yli-Urpo A, Kiesvaara J. Silica xerogel as an implantable carrier for controlled drug delivery – evaluation of drug distribution and tissue effects after implantation. Biomaterials 21 (2000) 193 – 198.

Kortesuo P, Ahola M, Kangas M, Kangasniemi I,Yli-Urpo A, Kiesvaara J. In vitro evaluation of sol-gel processed spray driedsilica gel microspheres as carrier in controlled drug delivery. Int. J. Pharm.200 (2000) 223 – 229.

Jokinen M, Peltola T,Veittola S, Rahiala H, Rosenholm JB. Adjustable biodegradation for ceramic fibres from silica sols. J. Eur. Cer. Soc. 20 (2000)1739 – 1748.

Ahola M, Kortesuo P, Kangasniemi I, KiesvaaraJ, Yli-Urpo A. In vitro release behaviour of toremifene citrate from sol-gel processed sintered solica xerogels. Drug Dev. & Ind. Pharm. 25 (1999) (8)955 – 959.