pK50─A Rigorous Indicator of Individual Functional Group Acidity/Basicity in Multiprotic Compounds.

In this work, we show that the apparent pKa measured by standard titration experiments is an insufficient measure of acidity or basicity of organic functional groups in multiprotic compounds─a frequent aspect of lead optimization in pharmaceutical research. We show that the use of the apparent pKa in this context may result in costly mistakes. To properly represent the group's true acidity/basicity, we propose pK50─a single-proton midpoint measure derived from a statistical thermodynamics treatment of multiprotic ionization. We show that pK50, which may be directly measured in specialized NMR titration experiments, is superior in tracking the functional group's acidity/basicity across congeneric series of related compounds and converges to the well familiar ionization constant in the monoprotic case.

A multi-method analysis of the interaction between humic acids and heavy metal ions.

Understanding of the interaction between humic acids (HAs) and heavy metal ions (HMIs) is essential for the assessment of environmental and health risks of HMIs. Multiple analyses, including fluorescence quenching of HAs; solution pH, zeta potential, and hydrodynamic size changes; and coprecipitation of HAs and HMIs, were carried out to investigate the interaction between two HAs and four HMIs (Ag+, Pb2+, Cd2+, and Cr3+). The HA-HMI interaction mainly included chemical complexation, H+-HMI exchange, electrostatic attraction, and flocculation. The chemical complexation between HAs and HMIs revealed by the Stern-Volmer quenching constant was ordered as Ag < Cd < Pb < Cr. HMIs replaced protons in the acidic functional groups of HAs and thus lowered the pH of the solution. The electrostatic interaction between the negatively charged HAs and HMIs reduced the electronegativity of HAs. Interaction with HMIs, especially the high-valent ions, induced aggregation of HAs, causing precipitation of both HAs and HMIs in the sorptive solution. Cr3+ flocculated and precipitated HAs, but at high concentrations, it reversed the surface charge of HAs and resuspended them. The HA-HMI interaction increased as the HA acidity and solution pH increased.

Surface changes of nanotopography by carbon ion implantation to enhance the biocompatibility of silicone rubber: an in vitro study of the optimum ion fluence and adsorbed protein.

Lower cellular adhesion and dense fibrous capsule formation around silicone breast implants caused by lower biocompatibility is a serious clinical problem. Preliminary work has shown that ion implantation enhances cell adhesion. Whether the biocompatibility is further enhanced by higher doses of carbon ion implantation and the mechanism by which ion implantation enhances biocompatibility remain unclear. In this study, five doses of carbon ions, which gradually increase, were implanted on the surface of silicone rubber and then the surface characteristics were surveyed. Then, cell adhesion, proliferation and migration were investigated. Furthermore, the vitronectin (VN) protein was used as a model protein to investigate whether the ion implantation affected the adsorbed protein on the surface. The obtained results indicate that enhanced cytocompatibility is dose dependent when the doses of ion implantation are less than 1 × 1016 ions/cm2. However, when the doses of ion implantation are more than 1 × 1016 ions/cm2, enhanced cytocompatibility is not significant. In addition, surface physicochemical changes by ion implantation induced a conformational change of the adsorbed vitronectin protein that enhanced cytocompatibility. Together, these results suggest that the optimum value of carbon ion implantation in silicone rubber to enhance biocompatibility is 1 × 1016 ions/cm2, and ion implantation regulates conformational changes of adsorbed ECM proteins, such as VN, and mediates the expression of intracellular signals that enhance the biocompatibility of silicone rubber. The results herein provide new insights into the surface modification of implant polymer materials to enhance biocompatibility. It has potentially broad applications in the biomedical field.

Nanoparticle surface charge impacts distribution, uptake and lymph node trafficking by pulmonary antigen-presenting cells.

Engineered nanoparticles have the potential to expand the breadth of pulmonary therapeutics, especially as respiratory vaccines. Notably, cationic nanoparticles have been demonstrated to produce superior local immune responses following pulmonary delivery; however, the cellular mechanisms of this increased response remain unknown. To this end, we investigated the cellular response of lung APCs following pulmonary instillation of anionic and cationic charged nanoparticles. While nanoparticles of both surface charges were capable of trafficking to the draining lymph node and were readily internalized by alveolar macrophages, both CD11b and CD103 lung dendritic cell (DC) subtypes preferentially associated with cationic nanoparticles. Instillation of cationic nanoparticles resulted in the upregulation of Ccl2 and Cxc10, which likely contributes to the recruitment of CD11b DCs to the lung. In total, these cellular mechanisms explain the increased efficacy of cationic formulations as a pulmonary vaccine carrier and provide critical benchmarks in the design of pulmonary vaccine nanoparticles. FROM THE CLINICAL EDITOR: Advance in nanotechnology has allowed the production of precise nanoparticles as vaccines. In this regard, pulmonary delivery has the most potential. In this article, the authors investigated the interaction of nanoparticles with various types of lung antigen presenting cells in an attempt to understand the cellular mechanisms. The findings would further help the future design of much improved vaccines for clinical use.

Evaluation of selected properties of a new root repair cement containing surface pre-reacted glass ionomer fillers.

OBJECTIVE: This study evaluated selected properties of a prototype root repair cement containing surface pre-reacted glass ionomer fillers (S-PRG) in comparison to mineral trioxide aggregate (MTA) and intermediate restorative material (IRM). MATERIALS AND METHODS: The antibacterial effect of S-PRG, MTA, and IRM cements was tested against Porphyromonas gingivalis and Enterococcus faecalis after 1 and 3 days of aging of the cements. The set cements were immersed in distilled water for 4 h to 28 days, and ion-releasing ability was evaluated. Initial and final setting times of all cements were evaluated using Gilmore needles. The push-out bond strength between radicular dentin and all cements was tested at different levels of the roots. RESULTS: S-PRG and IRM cements, but not MTA cement, demonstrated significant antibacterial effect against P. gingivalis. All types of cements exhibited significant antibacterial effect against E. faecalis without being able to eliminate the bacterium. S-PRG cement provided continuous release of fluoride, strontium, boron, sodium, aluminum, and zinc throughout all tested time points. Both initial and final setting times were significantly shorter for S-PRG and IRM cements in comparison to MTA. The push-out bond strength was significantly lower for S-PRG cement in comparison to MTA and IRM at coronal and middle levels of the roots. CONCLUSIONS: S-PRG cement demonstrated significant antibacterial effects against endodontic pathogens, multiple ion-releasing ability, relatively short setting time, and low bonding strength. CLINICAL RELEVANCE: S-PRG cement can be used as a one-visit root repair material with promising antibacterial properties and ion-releasing capacity.

Improving lithium therapeutics by crystal engineering of novel ionic cocrystals.

Current United States Food and Drug Administration (FDA)-approved lithium salts are plagued with a narrow therapeutic window. Recent attempts to find alternative drugs have identified new chemical entities, but lithium's polypharmacological mechanisms for treating neuropsychiatric disorders are highly debated and are not yet matched. Thus, re-engineering current lithium solid forms in order to optimize performance represents a low cost and low risk approach to the desired therapeutic outcome. In this contribution, we employed a crystal engineering strategy to synthesize the first ionic cocrystals (ICCs) of lithium salts with organic anions. We are unaware of any previous studies that have assessed the biological efficacy of any ICCs, and encouragingly we found that the new speciation did not negatively affect established bioactivities of lithium. We also observed that lithium ICCs exhibit modulated pharmacokinetics compared to lithium carbonate. Indeed, the studies detailed herein represent an important advancement in a crystal engineering approach to a new generation of lithium therapeutics.

Transepithelial transport of a natural cholinesterase inhibitor, huperzine A, along the gastrointestinal tract: the role of ionization on absorption mechanism.

During recent years there has been increasing interest in the Lycopodium alkaloid huperzine A as a potential therapeutic agent for neurodegenerative diseases. This study aimed to characterize huperzine A's permeability across the enterocyte barrier along the gastrointestinal tract with an emphasis on the effect of ionization on the drug absorption. Intestinal permeability of huperzine A was evaluated by in vitro Caco-2 and parallel artificial membrane permeation assay models and by the ex vivo Ussing chamber model. The permeability rate was strongly dependent on the degree of ionization and increased with elevation of the donor medium pH in all studied models. The transport of the unionized fraction was similar to the permeability of the markers for passive transcellular diffusion. Addition of the paracellular permeability modulator palmitoylcarnitine in the Caco-2 model led to significant enhancement in the permeability of the ionized huperzine A fraction. No evidence of active transport of huperzine A was detected in this study. The Ussing chamber model experiments showed similar drug permeability along the entire rat intestine. In conclusion, huperzine A permeates the intestinal border mainly by passive transcellular diffusion whereas some fraction, dependent on the degree of huperzine A ionization, is absorbed by the paracellular route. Huperzine A's permeability characteristics pave the way to the development of its oral extended release dosage form. The specific population of the potential users of huperzine A and the high potency of this molecule support the rationale for such a delivery.

The bioactivity and ion release of titanium-containing glass polyalkenoate cements for medical applications.

The ion release profiles and bioactivity of a series of Ti containing glass polyalkenoate cements. Characterization revealed each material to be amorphous with a T(g) in the region of 650-660°C. The network connectivity decreased (1.83-1.35) with the addition of TiO(2) which was also evident with analysis by X-ray photoelectron spectroscopy. Ion release from cements were determined using atomic absorption spectroscopy for zinc (Zn(2+)), calcium (Ca(2+)), strontium (Sr(2+)), Silica (Si(4+)) and titanium (Ti(4+)). Ions such as Zn(2+) (0.1-2.0 mg/l), Ca(2+) (2.0-8.3 mg/l,) Sr(2+) (0.1-3.9 mg/l), and Si(4+) (14-90 mg/l) were tested over 1-30 days. No Ti(4+) release was detected. Simulated body fluid revealed a CaP surface layer on each cement while cell culture testing of cement liquid extracts with TW-Z (5 mol% TiO(2)) produced the highest cell viability (161%) after 30 days. Direct contact testing of discs resulted in a decrease in cell viability of the each cement tested.

Temperature dependence of nickel ion release from nitinol medical devices.

Nitinol exhibits unique (thermo)mechanical properties that make it central to the design of many medical devices. However, nitinol nominally contains 50 atomic percent nickel, which if released in sufficient quantities, can lead to adverse health effects. While nickel release from nitinol devices is typically characterized using in vitro immersion tests, these evaluations require lengthy time periods. We have explored elevated temperature as a potential method to expedite this testing. Nickel release was characterized in nitinol materials with surface oxide thickness ranging from 12 to 1564 nm at four different temperatures from 310 to 360 K. We found that for three of the materials with relatively thin oxide layers, ≤ 87 nm nickel release exhibited Arrhenius behavior over the entire temperature range with activation energies of 80 to 85 kJ/mol. Conversely, the fourth ''black-oxide'' material, with a much thicker, complex oxide layer, was not well characterized by an Arrhenius relationship. Power law release profiles were observed in all four materials; however, the exponent from the thin oxide materials was approximately 1/4 compared with 3/4 for the black-oxide material. To illustrate the potential benefit of using elevated temperature to abbreviate nickel release testing, we demonstrated that a > 50 day 310 K release profile could be accurately recovered by testing for less than 1 week at 340 K. However, because the materials explored in this study were limited, additional testing and mechanistic insight are needed to establish a protective temperature scaling that can be applied to all nitinol medical device components.

Low-shrinkage-stress nanocomposite: An insight into shrinkage stress, antibacterial, and ion release properties.

The aims are: (a) To develop the first low-shrinkage-stress nanocomposite with antibacterial and remineralization capabilities through the incorporation of dimethylaminododecyl methacrylate (DMAHDM) and nanoparticles of amorphous calcium phosphate (NACP); (b) to investigate the effects of the new composite on biofilm inhibition, mechanical properties, shrinkage stress, and calcium (Ca) and phosphate (P) ion releases. The low-shrinkage-stress resin consisted of urethane dimethacrylate and triethylene glycol divinylbenzyl ether. Composite was formulated with 3% DMAHDM and 20% NACP. Mechanical properties, shrinkage stress, and degree of conversion were evaluated. Streptococcus mutans biofilm growth on composites was assessed. Ca and P ion releases were measured. The shrinkage stress of the low-shrinkage-stress composite containing 3% DMAHDM and 20% NACP was 36% lower than that of traditional composite control (p < 0.05), with similar degrees of conversion of 73.9%. The new composite decreased the biofilm colony-forming unit by 4 log orders and substantially reduced biofilm lactic acid production compared to control composite (p < 0.05). Incorporating DMAHDM to the low-shrinkage-stress composite did not adversely affect the Ca and P ion release. A novel bioactive nanocomposite was developed with low shrinkage stress, strong antibiofilm activity, and high levels of ion release for remineralization, without undermining the mechanical properties and degree of conversion.

Spontaneous formation of nanosized unilamellar polyion complex vesicles with tunable size and properties.

Fabrication of monodispersed, submicrometer-sized vesicles (nanosomes) that form through self-assembly possessing a thin and permeable membrane remains a significant challenge. Conventional fabrication of nanosomes through self-assembly of amphiphilic molecules often requires cumbersome processes using organic solvents combined with physical procedures (e.g., sonication, thermal treatment, and membrane filtration) to obtain unilamellar structures with a controlled size distribution. Herein, we report the first example of spontaneously formed submicrometer-sized unilamellar polyion complex vesicles (Nano-PICsomes) via self-assembly of a pair of oppositely charged PEG block aniomer and homocatiomer in an aqueous medium. Detailed dynamic light scattering and transmission electron microscopic analysis revealed that vesicle sizes can be controlled in the range of 100-400 nm with a narrow size distribution, simply by changing the total polymer concentration. Also, each Nano-PICsome was composed of a uniform single PIC membrane, the thickness of which is around 10-15 nm, regardless of its size. Fluorescence correlation spectroscopy measurement verified that Nano-PICsomes were able to encapsulate water-soluble fluorescent macromolecules in the inner water phase and release them slowly into the exterior. Moreover, cross-linking of the vesicle membrane allows tuning of permeability, enhancement in stability under physiological conditions, and preservation of size and structure even after freeze-drying and centrifugation treatment. Finally, Nano-PICsomes showed a long circulation time in the bloodstream of mice. Precise control of the particle size and structure of hollow capsules through simple aqueous self-assembly and easy modification of their properties by cross-linking is quite novel and fascinating in terms of ecological, low-cost, and low-energy fabrication processes as well as the potential utility in the biomedical arena.

In vivo liberation of silver ions from metallic silver surfaces.

In vivo liberation of electrically charged silver atoms/silver ions from metallic silver pellets, silver grids and silver threads placed in the brain, skin and abdominal cavity was proved by way of the histochemical technique autometallography (AMG). A bio-film or "dissolution membrane" inserted between the metallic surface and macrophages was recognized on the surface of the implanted silver after a short period of time. Bio-released silver ions bound in silver-sulphur nanocrystals were traced within the first 24 h in the "dissolution membrane" and the "dissolucytotic" macrophages. In animals that had survived 10 days or more, silver nanocrystals were detected both extra- and intracellularly in places far away from the implant including regional lymph nodes, liver, kidneys and the central nervous system (CNS). The accumulated silver was always confined to lysosome-like organelles. Dissolucytotic silver was extracellularly related to collagen fibrils and fibres in connective tissue and basement membranes. Our study demonstrates that (1) the number of bio-released silver ions depends on the size of the surface of the implanted silver, (2) the spread of silver ions throughout the body takes place primarily not only through the vascular system, but also by retrograde axonal transport. It is concluded that implantation of silver or silver-plated devices is not recommendable.

Titanates deliver metal ions to human monocytes.

Amorphous peroxotitantes (APT) are insoluble titanium-based particles that bind a variety of metal compounds with high affinity; these particles could be sequestered locally in a solid phase to deliver metal-based drugs. Previous studies have confirmed the 'biodelivery' of metals from metal-APT complexes to fibroblasts, but not monocytes. Our goal in the current study was to use monocytic cytokine secretion to assess delivery of gold or platinum-based compounds from APT to human THP1 monocytes. Cytokine secretion was not triggered by APT alone or metal-APT complexes. In monocytes activated by lipopolysaccharide (LPS), APT alone enhanced or suppressed IL1beta or IL6 secretion, yet TNFalpha secretion was unaffected. Complexes of APT and Au(III) or cis-platin altered LPS-activated IL6 or IL1beta secretion most, TNFalpha least. Our results suggest that the APT deliver metals to monocytes.

Effect of TiO2 doping on degradation rate, microstructure and strength of borate bioactive glass scaffolds.

A titanium-containing borate glass series based on the system (52-X) B2O3-12CaO-6P2O5-14Na2O-16ZnO-XTiO2 with X varying from 0, 5 and 15 mol% of TiO2 incorporated, identified as BRT0, BRT1 and BRT3, respectively, were used in this study. Scaffolds (pore sizes, 165-230 µm and porosity, 53.51-69.51%) were prepared using a polymer foam replication technique. BRT3 scaffolds exhibited higher compressive strength (7.16 ±â€¯0.22 MPa) when compared to BRT0 (6.02 ±â€¯0.47 MPa) and BRT1 (5.65 ±â€¯0.28 MPa) scaffolds with lower, or no, TiO2 content. The solubility of the scaffolds decreased as the TiO2 content increased up to 15 mol% when samples of each scaffold were immersed in DI water and the pH of all these extracts went up from 7.0 to 8.5 in 30 days. The cumulative ion release from the scaffolds showed significant difference with respect to TiO2 content; addition of 5 mol% TiO2 at the expense of borate (B2O3) decreased the ion release remarkably. Furthermore, it was found that for all three scaffolds, cumulative ion release increased with incubation time. The results indicate that the degradation rates and compressive strengths of borate bioactive glass scaffolds could be controlled by varying the amount of TiO2 incorporated, confirming their potential as scaffolds in TKA and rTKA.

Probing the molecular toxic mechanism of lead (II) ions with glutathione peroxidase 6 from Arabidopsis thaliana.

Along with non-biodegradability and accumulation in agricultural soil, lead (II) ions exert considerable harmful effects on plants even at trace amount, especially for the oxidative damages elicited by the lead ions-induced excessive reactive oxygen species (ROS). The glutathione peroxidases were reported to be correspondent with the oxidative stress induced by heavy metals. However, limited data are available about the potential hazardous mechanisms of the lead ions-induced oxidative damage to plants at molecular level. In this study, the harmful impacts of lead ions on Arabidopsis thaliana glutathione peroxidase 6 (AtGPX6) were assessed based on multi-spectroscopic measurements and molecular docking study. The characteristic fluorescence of AtGPX6 was quenched by lead ions with static mechanism at different temperatures. AtGPX6 exhibits a single binding site with lead ions, and then the complex formation was mainly driven by hydrogen bonding interaction and van der Waals forces on account of the negative ΔH and ΔS. The secondary structural changes were observed from the synchronous fluorescence, UV-visible absorption and Circular dichroism spectra, which led to loosen and unfold of the protein framework accompanied by the incremental hydrophobicity around the vicinity of the tryptophan residues. Therefore, this work illustrates the detailed binding mode between lead (II) ions and glutathione peroxidase 6 from Arabidopsis thaliana and the toxic effects on antioxidative defense system induced by lead ions at molecular level.

The synergistic effects of SrF2 nanoparticles, YSZ nanoparticles, and poly-ε-l-lysin on physicomechanical, ion release, and antibacterial-cellular behavior of the flowable dental composites.

Resin-based pit-and-fissure sealants (flowable resin composites) were formulated using bisphenol-A-glycerolatedimethacrylate (Bis-GMA)-triethylene glycol dimethacrylate-(TEGDMA)-diurethanedimethacrylate (UDMA) mixed monomers and multiple fillers, including synthetic strontium fluoride (SrF2) nanoparticles as a fluoride-releasing and antibacterial agent, yttria-stabilized zirconia (YSZ) nanoparticles as an auxiliary filler, and poly-ε-l-lysin (ε-PL) as an auxiliary antibacterial agent. Based on the physical, mechanical and initial antibacterial properties, the formulated nano-sealant containing 5 wt% SrF2, 5 wt% YSZ and 0.5 wt% ε-PL was selected as the optimal specimen and examined for ion release and cytotoxicity. The results showed an average release rate of 0.87 µg·cm-2·day-1 in the aqueous medium (pH 6.9) and 1.58 µg·cm-2·day-1 in acidic medium (pH 4.0). The maximum cytotoxicity of 20% toward human bone marrow mesenchymal stem cells (hMSCs) was observed according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) cytotoxicity assay and acridine orange staining test. A synergy between SrF2 nanoparticles and ε-PL exhibited a better antibacterial activity in terms of colony reduction compared to the other samples. However, the inclusion of SrF2 and ε-PL caused mechanically weakening of the sealants that was partly compensated by incorporation of YSZ nanoparticles (up to 10 wt%).

Time-dependent release of cobalt and chromium ions into the serum following implantation of the metal-on-metal Maverick type artificial lumbar disc (Medtronic Sofamor Danek).

INTRODUCTION: In total hip endoprosthetics and consequently for TDA, metal-on-metal combinations are used with the aim of reducing wear debris. In metal-on-metal TDA the release of metal ions has until now been secondary to the main discussion. MATERIALS AND METHODS: In order to investigate the ion release following the implantation of the metal-on-metal Maverick type artificial lumbar disc we measured the serum cobalt and chromium concentration following implantation of 15 Maverick TDAs (monosegmental L5/S1, n = 5; bisegmental L4/5 and L5/S1, n = 5; average age 36.5 years). Five healthy subjects (no metal implants) acted as a control group. The two measurements of the metals were carried out using the absorption spectrometry after an average of 14.8 and 36.7 months. RESULTS: In summary, the concentrations of cobalt and chromium ions in the serum at both follow-ups amounted on average to 3.3 microg/l (SD 2.6) for cobalt and 2.2 microg/l (SD 1.5) for chromium. These figures are similar to the figures shown in the literature following the implantation of metal-on-metal THA. After a comparison to the control group, both the chromium and cobalt levels in the serum showed visible increases regarding the first and the second follow-up. DISCUSSION: As there is still a significant release of cobalt and chromium into the serum after an average follow-up of 36.7 months a persistent release of these ions must be taken into consideration. Despite the evaluation of the systemic and local effects of the release of Cr/Co from orthopaedic implants has not yet been concluded, one should take into consideration an explanation given to patients scheduled for the implantation of a metal-on-metal TDA about these results and the benefits/risks of alternative combinations of gliding contact surfaces.

Systemic levels of metallic ions released from orthodontic mini-implants.

INTRODUCTION: Orthodontic mini-implants are a potential source of metallic ions to the human body because of the corrosion of titanium (Ti) alloy in body fluids. The purpose of this study was to gauge the concentration of Ti, aluminum (Al), and vanadium (V), as a function of time, in the kidneys, livers, and lungs of rabbits that had Ti-6Al-4V alloy orthodontic mini-implants placed in their tibia. METHODS: Twenty-three New Zealand rabbits were randomly divided into 4 groups: control, 1 week, 4 weeks, and 12 weeks. Four orthodontic mini-implants were placed in the left proximal tibia of 18 rabbits. Five control rabbits had no orthodontic mini-implants. After 1, 4, and 12 weeks, the rabbits were killed, and the selected tissues were extracted and prepared for analysis by graphite furnace atomic absorption spectrophotometry. RESULTS: Low amounts of Ti, Al, and V were detectable in the 1-week, 4-weeks, and 12-weeks groups, confirming that release of these metals from the mini-implants occurs, with diffusion and accumulation in remote organs. CONCLUSIONS: Despite the tendency of ion release when using the Ti alloy as orthodontic mini-implants, the amounts of metals detected were significantly below the average intake of these elements through food and drink and did not reach toxic concentrations.

ISI-mitigating modulation scheme using ion reaction for molecular communications.

Here, according to the type-based modulation technique, the authors develop a novel modulation scheme by utilising ion collision and reaction to mitigate inter-symbol interference (ISI) in diffusive molecular communication (MC) systems. Two types of ions are employed as messenger molecules that cause a chemical reaction in the medium. According to the residual molecules and chemical reaction, the proposed modulation scheme adaptively adjusts the number of emitted molecules, thereby guaranteeing that the number of molecules that arrived at the receiver remains at a stable level. The authors evaluate the performance of the proposed scheme by comparing it with the conventional binary molecule shift keying (BMoSK), BMoSK with power adjustment (BMoSK-PA), and ideal BMoSK (without ISI) modulation techniques via diffusion. Numerical results show that the bit error probability and channel capacity of the proposed modulation scheme are much closer to the ideal BMoSK modulation scheme compared to the conventional BMoSK and the BMoSK-PA modulation schemes.

Date pits activated carbon for divalent lead ions removal.

Phosphoric acid impregnated activated carbon from date pits (DPAC) was prepared through single step activation. Prepared DPAC was studied for its structural, elemental, chemical, surface and crystal nature. Adsorption ability of the DPAC was assessed through divalent lead ions separation studies. Effect of adsorbent dosage, contact time, pH, operating temperature and initial feed concentration on lead removal by DPAC was studied. Maximum Pb(II) adsorption capacity of 101.35 mg/g was attained for a contact time of 30 min and pH of 6 at 30°C. Increase in initial feed concentration enhanced the adsorption ability of DPAC and the rise in adsorbent dosage resulted in improved Pb(II) removal efficiency. Thermodynamic studies revealed that the lead adsorption on DPAC was exothermic and instantaneous in nature. Kinetic and equilibrium studies confirmed the suitability of pseudo-second order and Langmuir isotherm for divalent lead ions binding on DPAC. Reusability studies showed that HCl was the effective regeneration medium and the DPAC could be reused for a maximum of 4 times with slight reduction in Pb(II) removal efficiency (<10%). Results indicated the promising use of date pits biomass as a low cost and efficient starting material to prepare activated carbon for divalent lead ions removal.